Tag: echosounder

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Linda Kurtz: Hydrographic Surveys – Not your Mama’s Maps! August 17, 2019

NOAA Teacher at Sea

Linda Kurtz

Aboard NOAA Ship Fairweather

August 12-23, 2019


Mission: Cascadia Mapping Project

Geographic Area of Cruise: Northwest Pacific

Date: 8/17/2019

Weather Data from the Bridge

August 17th 2019

Latitude & Longitude: 43◦ 53.055’ N 124◦ 47.003’W
Windspeed: 13 knots
Geographic Area: @10-15 miles off of the Oregon/California coast
Cruise Speed:  12 knots
Sea Temperature 20◦Celsius
Air Temperature 68◦Fahrenheit

Future hydrographer button
Is this you?

Navigation is how Fairweather knows its position and how the crew plans and follows a safe route.  (Remember navigation from the last post?)  But what “drives” where the ship goes is Hydrographic survey mission.  There is a stunning amount of sea floor that remains unmapped, as well as seafloor that has not been mapped following a major geological event like an earthquake of underwater volcano.

Why is Hydrography important?  As we talked about in the previous post, the data is used for nautical safety, creating detailed maps of the ocean floor,  setting aside areas are likely abundant undersea wildlife as conservation areas, looking at the sea floor to determine if areas are good for wind turbine placement, and most importantly to the residents off the Pacific coast, locating fault lines — especially subduction zones which can generate the largest earthquakes and cause dangerous tsunamis.

In addition to generating the data needed to update nautical charts, hydrographic surveys support a variety of activities such as port and harbor maintenance (dredging), coastal engineering (beach erosion and replenishment studies), coastal zone management, and offshore resource development. Detailed depth information and seafloor characterization is also useful in determining fisheries habitat and understanding marine geologic processes.

The history of hydrographic surveys dates back to the days of Thomas Jefferson, who ordered a survey of our young nation’s coast.   This began the practice and accompanying sciences of the coastal surveys.  The practice of surveys birthed the science of Hydrography (which we are actively conducting now) and the accompanying science of Bathymetry (which we will go into on the next post.)  This practice continues of providing nautical charts to the maritime community to ensure safe passage into American ports and safe marine travels along the 95,000 miles of U.S. Coastline. 

Want to learn more about Hydrographic Survey history?  Click on THIS LINK for the full history by the NOAA.

Scientists have tools or equipment that they use to successfully carry out their research.  Let’s take a look at a few of the tools hydrographic survey techs use:

Want to learn more about the science of SONAR? Watch the video below.

ps://www.youtube.com/watch?v=8ijaPa-9MDs

On board Fairweather (actually underneath it) is the survey tool call a TRANSDUCER which sends out the sonar pulses.

Multibeam sonar illustration
Multibeam sonar illustration

The transducer on Fairweather is an EM 710- multibeam echo sounder which you can learn more about HERE. 

The Transducer is located on the bottom of the ship and sends out 256 sonar beams at a time to the bottom of the ocean.  The frequency of the 256 beams is determined by the depth from roughly 50 pings per second to 1 ping every 10 seconds.  The active elements of the EM 710 transducers are based upon composite ceramics, a design which has several advantages, which include increased bandwidth and more precise measurements. The transducers are fully watertight units which should give many years of trouble-free operation.  This comes in handy since the device in on the bottom of Fairweather’s hull!

Here is the transducer on one of the launches:

transducer
View of transducer on a survey launch

The 256 sonar beams are sent out by the transducer simultaneously to the ocean floor, and the rate of return is how the depth of the ocean floor is determined.  The rate of pulses and width of the “swath” or sonar beam array is affected by the depth of the water.  The deeper the water, the larger the “swath” or array of sonar beams because they travel a greater distance.  The shallower the water, the “swath” or array of sonar beams becomes narrower due to lesser distance traveled by the sonar beams.

The minimum depth that this transducer can map the sea floor is less than 3 meters and the maximum depth is approximately 2000 meters (which is somewhat dependent upon array size).  Across track coverage (swath width) is up to 5.5 times water depth, to a maximum of more than 2000 meters. This echo sounder is capable of reaching deeper depths because of the lower frequency array of beams. 

The transmission beams from the EM 710 multibeam echo sonar are electronically stabilized for roll, pitch and yaw, while they receive beams are stabilized for movements. (The movement of the ship) What is roll, pitch, and yaw? See below – these are ways the Fairweather is constantly moving!

Roll, Pitch, and Yaw
Roll, Pitch, and Yaw

Since the sonar is sent through water, the variable of the water that the sonar beams are sent through must be taken into account in the data. 

Some of the variables of salt water include: conductivity (or salinity) temperature, depth, and density.

Hydrographic scientists must use tools to measure these factors in sea water, other tools are built into the hydrographic survey computer programs. 

One of the tools used by the hydrographic techs is the XBT or Expendable Bathy Thermograph that takes a measurement of temperature and depth.  The salinity of the area being tested is retrieved from the World Ocean Atlas which is data base of world oceanographic data. All of this data is transmitted back to a laptop for the hydrographers.  The XBT is an external device that is launched off of the ship to take immediate readings of the water. 

Launching the XBT:  There is a launcher which has electrodes on it, then you plug the XBT probe to the launcher and then XBT is launched into the ocean off of the back of the ship.  The electrodes transmit data through the probe via the 750-meter copper wire.  The information then passes through the copper wire, through the electrodes, along the black wire, straight to the computer where the data is collected.  This data is then loaded onto a USB then taken and loaded into the Hydrographic data processing software.  Then the data collected by the XBT is used to generate the sound speed profile, which is sent to the sonar to correct for the sound speed changes through the water column that the sonar pulses are sent through.  The water column is all of the water between the surface and seafloor. Hydrographers must understand how the sound moves through the water columns which may have different densities that will bend the sound waves.  By taking the casts, you are getting a cross section “view” of the water column on how sound waves will behave at different densities, the REFRACTION (or bending of the sound waves) effects the data.

See how the XBT is launched and data is collected below!

  • Hydrotech Bekah Gossett preparing to cast
  • The XBT probe
  • The XBT launcher
  • I got to do a cast-
    thanks Bekah!
  • Instant readings from the XBT
  • Bekah downloading data from the XBT

Videos coming soon!

The other tool is the MVP or moving vessel profiler which takes measurements of conductivity, temperature, and depth.  These are all calculated to determine the density of the water.  This is a constant fixture on the aft deck (the back of the ship) and is towed behind the Fairweather and constantly transmits data to determine the speed of sound through water.  (Since sonar waves are sound waves.)

MVP and launching wench
MVP (left) and the launching wench (right)

The sonar software uses this data to adjust the calculation of the depth, correcting for the speed of sound through water due to the changes in the density of the ocean.  The final product?  A detailed 3d model of the seafloor!

current survey area
Our current survey area! (Thanks Charles for the image!)

All of this data is run through the survey software.  See screen shots below of all the screens the hydrographers utilize in the course of their work with explanations.  (Thanks Sam!)  It’s a lot of information to take in, but hydrographic survey techs get it done 24 hours a day while we are at sea.  Amazing!  See below:

ACQ software screenshot
Hydrographic Survey “Mission Control”
HYPACK Acquisition Software
HYPACK Acquisition Software
Real time coverage map
Real time coverage map

Did You Know?  An interesting fact about sonar:  When the depth is deeper, a lower frequency of sonar is utilized.  In shallower depths, a higher sonar frequency. (Up to 900 meters, then this rule changes.)

Question of the Day:  Interested in becoming a hydrographic survey tech?  See the job description HERE.

Challenge yourself — see if you can learn and apply the new terms and phrases below and add new terms from this blog or from your research to the list!

New Terms/Phrases:

Multibeam sonar

Sound speed

Conductivity

Salinity

Sonar

Sound waves

Refraction

Water column

Roll, Pitch, and Yaw

Animals seen today:

Humpback Whale

Bathymetry and USGS friends coming soon!

Plot room
Hydro-technician Sam Candio (right) collaborating with USGS Research Geologist James Conrad and Physical Scientist Peter Dartnell.
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Brad Rhew: The Sounds of the Sea, July 31, 2017

NOAA Teacher at Sea

Brad Rhew

Aboard NOAA Ship Bell M. Shimada

July 23 – August 7, 2017

 

Mission: Hake Fish Survey

Geographic Area of Cruise: Northwest Pacific Ocean, off of the coast of Oregon

Date: July 31, 2017

 

Weather Data from the Bridge

Latitude: 44 49.160 N
Longitude 124 26.512

Temperature: 59oF
Sunny
No precipitation
Winds at 25.45 knots
Waves at 4-5ft

 

Science and Technology Log

TAS Rhew 7-31 acoustics lab2
Inside the acoustics lab

The scientists on the Hake survey project are constantly trying to find new methods to collect data on the fish. One method used is acoustics. Scientists Larry Hufnagle and Dezhang Chu are leading this project on the Shimada. They are using acoustics at a frequency of 38 kHz to detect Pacific Hake. Density differences between air in the swimbladder, fish tissue, and the surrounding water allows scientists to detect fish acoustically.

The purpose of the swim bladder in a fish is to help with the fish’s buoyancy. Fish can regulate the amount of gas in the swim bladder to help them stay at a certain depth in the ocean. This in return decreases the amount of energy they use swimming.

TAS Rhew 7-31 echosounder
The screen shows the data collected by the echosounder at different frequency levels.

Larry and Chu are looking at the acoustic returns (echoes) from 3 frequencies and determining which are Hake. When the echosounder receives echoes from fish, the data is collected and visually displayed. The scientists can see the intensity and patterns of the echosounder return and determine if Hake are present.

The scientists survey from sunrise to sunset looking at the intensity of the return and appearances of schools of fish to make the decisions if this is an area to fish.

TAS Rhew 7-31 scientists Larry and Chu
Scientists Larry Hufnagle (left) and Dezhang Chu (right) monitor the nets and echosounder while fishing for hake.

The ultimate goal is to use this data collected from the echosounder to determine the fish biomass. The biomass determined by the survey is used by stock assessment scientist and managers to manage the fish stock.

Personal Log

Everyday aboard the Shimada is a different experience. It has been amazing to be able to go between the different research labs to learn about how each group of scientists’ projects are contributing to our knowing more about Hake and marine ecosystems. My favorite part so far has been helping with the sampling of Hake. Some people might find dissecting fish after fish to determine length, sex, age, and maturity to be too much. However, this gives me an even better understanding and respect for what scientists do on a daily basis so we can have a better understanding of the world around us. We have also caught other fascinating organisms that has helped me explore other marine species and learn even more about their role in the ocean.

Even though the wind is a little strong and the temperatures are a little chilly for my southern body I wouldn’t trade this experience for anything…especially these amazing sunsets…

TAS Rhew 7-31 sunset
View of sunset over the Pacific Ocean from NOAA Ship Bell M. Shimada

Did You Know?

Before every fishing operation on the boat we must first do a marine mammal watch. Scientists and other crew members go up to the bridge of the boat to see if any mammals (whales, seals, dolphins) are present near the boat. This is to help prevent these animals from being harmed as we collect fish as well as making sure we are not running a risk of these mammals getting caught in the fishing nets.

Fascinating Catch of the Day!

Today’s fun catch in the net was a Brown Catshark! These creatures are normally found in the deeper parts of the Pacific Ocean. They are typically a darker brown color with their eyes on the side of their head. Their skin is very soft and flabby which can easily lead to them being harmed. They have two dorsal fins and their nostrils and mouth on the underside of their body. One of the sharks we caught was just recently pregnant.

Two brown catsharks
Catsharks have two dorsal fins (on their backs)
Catsharks’ nostrils and mouths are on the undersides of their bodies
Catshark egg sacks

 

TAS Rhew 7-31 catshark egg sack string
This catshark was recently pregnant; the yellow stringy substance is from an egg sack.

Notice to yellow curly substance coming out of the shark? That is from the egg sac. Sharks only produce one egg sac at a time. It normally takes up to a full year before a baby shark to form!

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Marsha Lenz: Celebrating Science and the Solstice, June 21, 2017

NOAA Teacher at Sea

Marsha Lenz

Aboard Oscar Dyson

June 8-28, 2017

Mission: MACE Pollock Survey

Geographic Area of Cruise: Gulf of Alaska

Date: June 21, 2017

thumb_IMG_2352_1024.jpg
Though modern technology is used daily, one can still find traditional charting tools on the Bridge.

Weather Data from the Bridge

Latitude: 55 15.0 N

Longitude: 160 06.7 W

Time: 1300

Visibility: 10 Nautical Miles

Wind Direction: VAR

Wind Speed: LT

Sea Wave Height: <1 foot

Barometric Pressure: 1003.4 Millibars

Sea Water Temperature: 9.8°C

Air Temperature: 7.0°C

Science and Technology Log

            We have been surveying transect lines (sometimes we fish, sometimes we don’t). During the times that we aren’t fishing, I find myself looking out at the ocean A LOT! During these quiet times on the ship, I am reminded of how large the oceans are. I found a quiet window to sit by in the Chem Lab and enjoy watching as the waves dance off of the side of the ship.

IMG_1975
Abigail enjoys singing to the fish.

During some of these times when we are not collecting data from fish, identifying species from the DropCam, or preparing for the next haul, I find myself reading, which is a luxury all in itself. A friend of mine lent me to book to read and as I was reading the other day, the author quoted Jules Verne, author of 20,000 Leagues Under the Sea. Verne said, “Science, my lad, is made up of mistakes, but they are mistakes which it is useful to make, because they lead little by little to the truth.” I found this to be fitting for what I am doing on this survey, for the three weeks that I am a Teacher At Sea.   Though I am surrounded by trained and educated professionals, I have realized that mistakes still happen and are something to be expected.   They happen regularly. Often, actually. And, it’s a good thing that they do. They are important for learning. When humans make mistakes, hopefully, we can adjust our actions/behaviors to reduce the chances of that same “mistake” from happening again. When applied to science, the same idea is also true. When  we can collect data from something that we are studying, we learn about the ways that it interacts with its surroundings. Through these findings, we not only learn more about what we are studying, but then take measures to protect its survival.

We had a real experience like this happen just the other day. For days, the “backscatter” was picking up images of fish that the scientists didn’t think were pollock on the bottom of the ocean. Backscatter is what the scientists use to “see” different groups of fish and quantify how many are in the water. The ship uses various echosounders.  Several times, the science team decided to collect fish samples from these areas.  Every time that they decided to “go fishing”, we pulled up pollock. The team was baffled. They had a hypothesis as to why they were not catching what they thought they saw on the backscatter. They thought that it was rockfish that were hanging around rocks, but the pollock were being caught as the net went down and came back up.  Finally, after several attempts of not catching anything but pollock, they decided to put down the DropCam and actually try to see what was going on down there.

At that point, the Chem lab was filled with scientists. Everyone wanted to see what was going to show up on the monitor. The NOAA Corps Commanding Officer even came to see what was going to show up on the monitor.  The room will filled with excitement.

 

Abigail steers the DropCam and watches the monitor simultaneously.

We see rockfish!

          It was just as they predicted!  The rockfish were hanging out in the rocks.  It was a moment of great satisfaction for the scientists. They were able to identify some of the fish on the backscatter that was causing them so much confusion! Yay, science!

19433465_10211635923631739_1269694918_n
This is a pollock!

Later in the day, we went fishing and collected the usual data (sex, length, weight, etc.) from the pollock.  There are usually 4 of us at a time in the Fish lab.  We are getting into a routine in the lab and I am getting more familiar with my responsibilities and duties. I start by controlling the door release, which controls the amount of fish released onto the conveyor belt. After all of the fish have been weighed, I separate the females and males.  Once that has been done, I take the lengths of a sample of the fish that we caught. When I finish, I assist Ethan and Abigail in removing and  collecting the otoliths from a selected fish sample.  Then, its clean-up time.  Though we all have appropriate gear on, I somehow still end up having fish scales all over me.  Imagine that!

Every time that we “go fishing”, a “pocket net” is also deployed.  This is a net that has finer mesh and is designed to catch much smaller marine life.  On this haul, we caught squid, age “zero” pollock, and isopods.

We also found some young Magister Armhook squid.
Age “Zero” pollock under under the age of 1.
Parasitic isopods attach themselves to the pollock and suck their blood.
We record the mass and length of everything caught.
We also caught a larval flatfish and an Age “Zero” pollock.

In the evening, we headed towards Morzhovoi Bay.  There, we were greeted by a pod of Pacific white-sided dolphins.  They spent some time swimming next to us.  When they discovered that we were not that interesting, they swam off.  They did leave us though with a great sense of awe and appreciation (and a few great pictures!).

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Personal Log

Happy Summer Solstice!  Today is the longest day of the year!  We have had some spectacular days. We were all excited as we got up this morning to welcome the rising of the sun. We woke up and were holding position in front of Mt. Pavlof.  We saw the sunrise and went up to the  Flying Bridge to do some morning yoga.  After a wonderful breakfast of a bagel with cream cheese, salmon, Larrupin sauce, and Slug Slime, I went back up to the Bridge to get a full 360 degree view of the bay.  There I saw a humpback whale swimming around.  This will definitely be a summer solstice to remember!

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Did You Know?

A humpback whale is about the size of a school bus and weighs about 40 tons! They also communicate with each other with songs under the water.

sidenote: I know I wrote in my last blog that I was going to discuss the fishing process today, but there were so many other amazing things that happened that it is going to have to wait until next time. Sorry!

 

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Cassie Kautzer: Alaska or Bust! August 11, 2014

NOAA Teacher at Sea
Cassie Kautzer
(Almost) Aboard NOAA Ship Rainier
August 16 – September 5, 2014

Mission: Hydrographic Survey
Geographical area of cruise: Cold Bay, Alaska
Date: August 11, 2014

Personal Log

Hi! My name is Cassie Kautzer and I am writing to you from my couch in Northwest Arkansas. I am hiding inside with the air conditioning today because my thermometer shows it being 95 degrees Fahrenheit, and that is too hot for this former Wisconsin girl! I am finishing packing and doing some final research before I head to Alaska on August 16! (I am also very much looking forward to cooler temperatures!)

Science girl power!
Alaska or Bust! This science girl is ready!

 

I am a fifth grade teacher at Monitor Elementary in Springdale, Arkansas! I have loved MONITOR and all my little Mallards since 2008 when I had the honor of joining the Monitor Team. Monitor Elementary houses a very diverse population of around 800 students each year. This school year, I will have the pleasure of teaching science to 112 of those students, and I cannot wait to share this amazing experience with them! Since Arkansas is not a coastal state, neither my students nor I have a lot of experience with marine ecology or tidal influences. In the Paleozoic Era, however, the entire state was covered by relatively shallow ocean, the Ouachita Basin.

I applied for this wonderful learning opportunity for several reasons:

• I am like my students, I learn by DOING! I can’t take all of my students with me (though I would if I could), so I will learn and gather new information, first hand, and take back pictures, videos, stories, lessons, and activities to share with them!
• I want my students to see the bigger picture–how is our life in Arkansas affected by oceans, tides, floods, erosion?
• I want my students to see the scientific opportunities, jobs, and careers that are available to them! I want to help inspire future scientists!
• I want my girls to see women working in scientific fields!
• And… I love adventure, and exploring and learning about our beautiful world! I will not fear the unknown; I will learn and grow as I figure it out!

Whitaker Point, Hawksbill Crag Trail, Arkansas
On top of the world! I made my first visit to Whitaker Point in Arkansas this summer!

My mission this summer, from August 16 – September 5, will be a Hydrographic Survey aboard the NOAA Ship Rainier. NOAA is the National Oceanic and Atmospheric Administration. NOAA’s mission is to understand the Earth’s environment in order to conserve and care for marine (ocean) resources. The Rainier is “one of the most modern and productive survey platforms of its type in the world” and uses multibeam sonar systems to “cover large survey areas in a field season. The ship’s hydrographers acquire and process massive amounts of data and create high-resolution, three-dimensional terrain models of the ocean floor.”  Those models can then be used to identify obstructions and shoals along the bottom of the ocean that are dangerous for navigating ships.  (http://www.omao.noaa.gov/publications/ra_flier.pdf) Hydro ships, like the Rainier, map the ocean floor to help with safe navigation of the seas. Knowing the depth and make-up of the ocean floor surrounding Alaska will benefit all the vessels and ships, large and small, passing through the Gulf of Alaska. Activities onboard can include echosounding, tide gauge installation, shoreline surveying, verification, and mapping, and data processing.

 

NOAA ship Rainier, named for Mt. Rainier - a volcanic cone in Washington state that rises 14,410 feet above sea level. Photo courtesy of NOAA.
NOAA ship Rainier, named for Mt. Rainier – a volcanic cone in Washington state that rises 14,410 feet above sea level. Photo courtesy of NOAA.

So what does all of that mean?? I am about to find out! NOAA’s Teacher at Sea program aims to provide me, the teacher, with real-world research experience through work with world-renowned scientists, to allow unique insights into oceanic and atmospheric research crucial to our world. To this end, I truly believe the best way to learn is by getting ones hands dirty and trying to figure things out. So, on August 16 I will head to Alaska and meet up the Rainier in Kodiak, AK. On August 18 we will depart from Kodiak and head toward Cold Bay to begin our hydrographic survey mission.

Right now, I have more questions than answers: What will it be like without land beneath my feet for three whole weeks? What hours will I work? How am I going to learn all the crew members’ names? Will I get sea sick? What is echosounding? Will I get to go out on a launch? What marine life am I going to see? Will I ever want to leave Alaska? I guess I am about to find out!

For My Students

Can you find out…..?

1. How can I track the distance and speed I am traveling at while on the Rainier? (What units would I use to measure and share this information with you?)

2. When I am on the Rainier, weather information will be shared in degrees Celsius. How can I convert that information to degrees Farenheit so all of my non-science friends can understand?

“Leave a Reply” at the very bottom of this page! I am looking forward to answering (or trying to answer) your questions and sharing this epic learning adventure with you!

And of course, as Will.I.Am wrote and sang, and I kareoked to my students all year, “Reach for the Stars” and you’re sure to end up in the “Hall of Fame!”

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Mary Murrian: My First Days in Dutch Harbor, July 6, 2014

NOAA Teacher at Sea 

Mary Murrian

Aboard NOAA Ship Oscar Dyson

July 4 – 22, 2014

Mission: Annual Walleye Pollock Survey

Geographical Area of Cruise: Bering Sea North of Dutch Harbor

Date: Sunday, July 6th, 2014

Weather Data from the Bridge:

Wind Speed: 6 kts

Air Temperature: 8.6 degrees Celsius

Weather conditions: Hazy

Barometric Pressure: 1009.9

Latitude: 5923.6198  N

Longitude: 17030.6395  W

 

Science and Technology Log

Part One of the Survey Trawl: Getting Ready to Fish

This is a picture of a pollock from our first trawl.
This is a picture of a pollock from our first trawl.

Today is my second day aboard the Oscar Dyson.  We are anxiously waiting for the echosounder (more information on echosounder follows) to send us a visual indication that a large abundance of fish is ready to be caught.  The point of the survey is to measure the abundance of Walleye Pollock throughout specific regions in the Bering Sea and manage the fisheries that harvest these fish for commercial use to process and sell across the world.  The Walleye Pollock are one of the largest populations of fish.  It is important to manage their populations due to over-fishing could cause a substantial decrease the species.  This would be detrimental to our ecosystem.  The food web [interconnecting food chains; i.e. Sun, plants or producers (algae), primary consumers, animals that eat plants (zooplankton), secondary consumers, animals that eat other animals (pollock), and decomposers, plants or animals that break down dead matter (bacteria)] could be altered and would cause a negative effect on other producers and consumers that depend on the pollock for food or maintain their population.

The main food source for young pollock is copepods, a very small marine animal (it looks like a grain of rice with handle bars).  They also eat zooplankton (animals in the plankton), crustaceans, and other bottom dwelling sea life.  On the weird side of the species, adult pollock are known to eat smaller pollock.  That’s right, they eat each other, otherwise known as cannibalism.  Pollock is one of the main food sources for young fur seal pups and other marine life in Alaskan waters.  Without the pollock, the food web would be greatly altered and not in a positive way.

How do we track the pollock?

Pollock
Pollock

Tracking begins in the acoustics lab.  Acoustics is the branch of science concerned with the properties of sound.  The acoustics lab on board the Oscar Dyson, is the main work room where scientists can monitor life in the ocean using an echosounder which measures how many fish there are with sound to track the walleye pollock’s location in the ocean.  They also use the ships’s GPS (Global Positioning System), a navigation system, to track the location of the NOAA vessel and trawl path.

Echo Sounder
Sonar Screen

What is sonar and how does it work? 

Sonar (sound ranging & navigation;  it’s a product of World War II) allows scientists to “see” things in the ocean using sound by measuring the amount of sound bouncing off of objects in the water.  On this survey, sonar images are displayed as colors on several computer monitors, which are used to see when fish are present and their abundance.  Strong echoes show up as red, and weak echoes are shown as white.  The greater the amount of sound reported by the sonar as red signals, the greater the amount of fish.

Echo Sonar Screen Showing the patterns of echos from the ocean.
Echo Sonar Screen Showing the patterns of echos from the ocean.

How does it work?  There is a piece of equipment attached to the bottom of the ship called the echosounder.  It sends pings (sound pulses) to the bottom of the ocean and measures how much sound bounces back to track possible fish locations.   The echo from the ocean floor shows up as a very strong red signal.   When echoes appear before the sound hits the ocean floor, this represents the ping colliding with an object in the water such as a fish.

The scientists monitor the echosounder signal so they can convey to the ships’s bridge and commanding officer to release the nets so that they can identify the animals reflecting the sound.  The net catches anything in its path such as jellyfish, star fish, crabs, snails, clams, and a variety of other fish species. Years of experience allows the NOAA scientists the ability to distinguish between the colors represented on the computer monitor and determine which markings represent pollock versus krill or other sea life.  We also measure the echoes at different frequencies and can tell whether we have located fish such as pollock, or smaller aquatic life (zooplankton). The red color shown on the sonar screen is also an indicator of pollock, which form dense schools.  The greater amount of red color shown on the sonar monitor, the better opportunity to we have to catch a larger sample of pollock.

The Science Team Wonderful group of people.

Once we have located the pollock and the net is ready, it is time to fish.  It is not as easy as you think, although the deck hands and surveyors make it look simple.  In order to survey the pollock, we have to trawl the ocean.  Depending on the sonar location of the pollock, the trawl can gather fish from the bottom of floor, middle level and/or surface of the ocean covering preplanned locations or coordinates. Note: Not all the fish caught are pollock.

The preplanned survey path is called transect lines with head due north for a certain distance. When the path turns at a 90 degree angle west (called cross-transect lines) and turns around another 90 degree angle heading back south again.  This is repeated numerous times over the course of each leg in order to cover a greater area of the ocean floor.  In my case we are navigating the Bering Sea.  My voyage, on the Oscar Dyson is actually the second leg of the survey, in which, scientists are trawling for walleye pollock.  There are a total of three legs planned covering a distance of approximately 6,200nmi (nautical miles, that is).

Trawling is where we release a large net into the sea located on the stern (the back of the boat).  Trawling is similar to herding sheep.  The fish swim into the net as the boat continues to move forward, eventually moving to the smaller end of the net.  Once the sonar screen (located on a computer monitor) shows that we have collected a large enough sample of pollock, the deck hands reel the net back on board the boat.

 

The crew are beginning to release the trawl net.
The crew are beginning to release the trawl net.

This is the stern of the boat where the trawl net gets released into the ocean.
This is the stern of the boat where the trawl net gets released into the ocean.

We have caught the fish, now what?  Stay tuned for my exciting experience in the wet lab handling the pollock and other marine wild life.  It is most certainly an opportunity of a lifetime.

Personal Log

What an adventure!

I was lucky enough to spend a day exploring Dutch Harbor, Alaska before departing on the pollock survey across the Bering Sea. It took me three plane rides, several short lay-overs and and a car ride to get here, a total of 16 hours. There is a four hour time difference between Dutch Harbor and Dover, Delaware. It takes some getting used to, but definitely worth it. The sun sets shortly after 12:00 midnight and appears again around 5:00 in the morning. Going to sleep when it’s still daylight can be tricky. Thank goodness I have a curtain surrounding my bed. Speaking of the bed, it is extremely comfortable. It is one of those soft pillow top beds. Getting in and out of the top bunk can be challenging. I haven’t fallen yet.

My bed is the top bunk.
My bed is the top bunk.

During my tour through the small town of Dutch Harbor, I have encountered very friendly residents and fishermen from around the world.  I was fortunate to see the U.S. Coast Guard ship Healy docked at the harbor. What a beautiful vessel.  Dutch Harbor has one full grocery store (Safeway) just like we have in Delaware, with the exception of some of the local Alaska food products like Alaska BBQ potato chips. They have a merchant store that sells a variety of items ranging from food, souvenirs, clothing, and hardware. They have three local restaurants and a mom and pop fast food establishment. One of the restaurants is located in the only local Inn the Aleutian hotel, which also includes a gift shop. Dutch Harbor is home to several major fisheries. Dutch Harbor is rich in history and is home to the native Aleutian tribe. I took a tour of their local museum. It was filled with the history and journey of the Aleutian people. While driving through town, I got a chance to see their elementary and high school. They both looked relatively new. Dutch Harbor is also home to our nation’s first Russian Orthodox Church. Alaska is our 50th state and was purchased from Russia in 1867.

Me and the Oscar Dyson
Mary Murian in front of the Oscar Dyson

A very funny photo of me in my survival suit.
A very funny photo of me in my survival suit.

One of the coolest parts of my tour was walking around the area known as the “spit”. The “spit” is located directly behind the airport. I’m told it is called the “spit” because the land and water are spitting distance in length and width. We walked along the shoreline and discovered hundreds of small snails gathered around the rocks. We also found hermit crabs, starfish, sea anemones, jellyfish, and red algae. We saw red colored water, which is a bloom or a population explosion of tiny algae that get so thick that they change the color of the water.

One of numerous amazing views in Dutch Harbor
One of numerous amazing views in Dutch Harbor

tas 2014 day 1 and perboarding july 2-4th 089
Starfish

Another animal in abundance in Dutch Harbor is the bald eagle. There is practically one on every light post or tall structure. Often the bald eagles are perched in small groups. Watch out: if you walk too close to a nesting mother, she will come after you. They are massive, regal animals. I never get tired of watching them.

We had to watch our step, the snails were everywhere along the shoreline of the Spit.
We had to watch our step, the snails were everywhere along the shoreline of the Spit.

A bald eagle hoping to find some lunch.
A bald eagle hoping to find some lunch.

Russian Orthodox Church in Dutch Harbor, AK
Russian Orthodox Church in Dutch Harbor, AK

Did You Know?

Did you know that Alaska’s United States Coast Guard vessel has the ability to break through sea ice? 

This is especially helpful if you want to study northern areas, which are often ice covered, in the winter, and to assist a smaller boat if it gets trapped in the ice.

U.S. Coast Guard Ship Healy docked at the Spit.
U.S. Coast Guard Ship Healy docked at the Spit.

Did you know that scientists set time to Greenwich Mean Time (GMT) which is the time in a place in England?

This reduces confusion (e.g. related to daylight savings, time zones) when the measurements are analyzed.

Key Vocabulary:

Carnivore

Primary Consumer

Secondary Consumer

Nautical Miles

Trawling

Stern

Acoustics

Decomposers

Echosounder

Meet the Scientist:

Alex De Biologist
Alex De Robertis Chief Scientist

Leg II Chief Scientist Dr. Alex De Robertis

Title: NOAA Research Fishery Biologist (10 years)

Education:  UCLA Biology Undergraduate Degree

Scripps Institute Oceanography San Diego, CA PhD.

Newport, Oregon Post Doctorate work

Living Quarters:

Born in Argentina and moved to England when one-year old.

Lived in Switzerland and moved to Los Angeles,CA at the age of 13.

Currently lives in Seattle, Washington, and he has two kids aged one and five.

Job Responsibilities:

Responsible for acoustic trawl surveying at Alaska Fisheries Science Center

Was able to help with the Gulf of Mexico oil spill clean-up using the same echo sonar used on trawl surveys.

What is cool about his work:

He enjoys his work, especially the chance to travel to different geographic locations and meet new people.  “You never know what you are going to encounter; there is always a surprise or curve ball, when that occurs you adjust and just go with it”.

In the near future, he would love to see or be part of the design for an autonomous ocean robot that will simplify the surveying process.

He has been interested in oceans and biology since a small boy.  He remembers seeing two divers emerge from the sea and was amazed it was possible.

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Melissa George: Do You Hear What I Hear? July 28, 2013

NOAA Teacher at Sea
Melissa George
Aboard NOAA Ship Oscar Dyson
July 22 – August 9, 2013

Mission:  Pollock Survey
Geographical Area of Cruise:  Gulf of Alaska
Date:  Sunday, July 28, 2013

Current Data From Today’s Cruise

Weather Data from the Bridge 
Sky Condition:  Cloudy
Temperature:  14° C
Wind Speed:  4 knots
Barometric Pressure:  1025.1 mb
Humidity:  90%

Sun and Moon Data 
Sunrise:  5:57 am
Sunset:  10:34 pm

Moonrise:  11:52 pm  (July 27, 2013)
Moonset:  2:35 pm

Geographic Coordinates at 

Latitude:  59° 53.3′ N
Longitude:  149° 00.0′ W

The ship’s position now can be found by clicking:  Oscar Dyson’s Geographical Position

False Point on Kenai Peninsula (viewed this morning through the fog)
False Point on Kenai Peninsula (viewed this morning through the fog)

Science and Technology Log

How do scientists use acoustics to locate Pollock (and serendipitously other ocean creatures)?

Scientists aboard the NOAA Research Vessel Oscar Dyson use acoustic, specifically hydroacoustic data, to locate schools of fish before trawling.  The trawl data provide a sample from each school and allow the NOAA scientists to take a closer look by age, gender and species distribution.  Basically, the trawl data verify and validate the acoustics data.  The acoustics data, collected in the Gulf of Alaska in systematic paths called transects, combined with the validating biological data from the numerous individual trawls, give scientists a very good estimate for the entire Walleye pollock population in this location.

This screen is showing the echogram from the EK 60 echosounder during a trawl at 83.13 meters. The red line in the middle of the screen is the ocean floor. The colorful spikes above the red line indicate “backscatter” that is characteristic of capelin, a small fish that pollock feed on.
This screen is showing the echogram from the EK 60 echosounder during a trawl at 83.13 meters. The red line in the middle of the screen is the ocean floor. The colorful spikes above the red line indicate “backscatter” that is characteristic of capelin, a small fish that pollock feed on.

Hydroacoustics  (from Greek words: hydro meaning “water”  and  acoustics meaning “sound”) is the study of sound in water.  Sound is a form of energy that travels in pressure waves. In water, sound can travel great distances without losing strength and can travel fast, roughly 4.3 times faster in water than in air (depending on temperature and salinity of the water).

Click on this picture to see how sound travels from various ocean creatures through water. (Photo from sciencelearn.org)
Click on this picture to see how sound travels from various ocean creatures through water. (Photo from sciencelearn.org)

The Oscar Dyson has powerful, extremely sensitive, carefully calibrated, scientific acoustic instruments or “fish finders” including the five SIMRAD EK60 transducers located on the bottom of the centerboard, the SIMRAD ME70 multibeam transducer located on the hull, and a pair of SIMRAD ITI transducers on the trailing edge of the centerboard.

Image of acoustic instruments on the Oscar Dyson. (Photo courtesy of NOAA Teacher at Sea Program)
Image of acoustic instruments on the Oscar Dyson. (Photo courtesy of NOAA Teacher at Sea Program)

This “fish-finder” technology works when transducers emit a sound wave at a particular frequency and detect the sound wave bouncing back (the echo) at the same frequency.  When the sound waves return from a school of fish, the strength of the returning echo helps determine how many fish are at that particular site.

The green ship’s transducer is sending out sound waves towards the fish. The waves bounce back echoes towards the ship that are received by the transducer. (Photo courtesy of Oracle Thinkquest)
The green ship’s transducer is sending out sound waves towards the fish. The waves bounce back echoes towards the ship that are received by the transducer. (Photo courtesy of Oracle Thinkquest)

Sound waves bounce or reflect off of fish and other creatures in the sea differently.  Most fish reflect sound energy sent from the transducers because of their swim bladders, organs that fish use to stay buoyant in the water column.  Since a swim bladder is filled with air, it reflects sound very well.   When the sound energy goes from one medium to another, there is a stronger reflection of that sound energy.  In most cases, the bigger the fish, the bigger the swim bladder; the bigger the swim bladder, the more sound is reflected and received by the transducer.  The characteristic reflection of sound is called target strength and can be used to detect the size of the fish. This is why fish that have air-filled swim bladders show up nicely on hydroacoustic data, while fish that lack swim bladders (like sharks) or that have oil or wax filled swim bladders (like Orange Roughy), have weak signals.

The above picture shows the location of the swim bladder. (Photo courtesy of greatneck.k12.ny.us)
The above picture shows the location of the swim bladder. (Photo courtesy of greatneck.k12.ny.us)

These reflections of sound (echoes) are sent to computers which display the information in echograms.  The reflections showing up on the computer screen are called backscatter.  The backscatter is how we determine how dense the fish are in a particular school.  Scientists take the backscatter that we measure from the transducers and divide that by the target strength for an individual and that gives  the number of individuals that must be there to produce that amount of backscatter.  For example, a hundred fish produce 100x more echoes than a single fish.  This information can be used to estimate the pollock population in the Gulf of Alaska.

The above picture shows a computer screen with dense red “backscatter” characteristic of large amount of fish. The yellow lines above and below the backscatter show the location of the trawl lines.
The above picture shows a computer screen with dense red “backscatter” characteristic of large amount of fish, most likely pollock. The yellow lines above and below the backscatter show the location of the trawl lines.

Personal Log: 

Safety

Safety Announcements Don the Walls of the Oscar Dyson
Safety Announcements Don the Walls of the Oscar Dyson

Continuing with Maslow’s hierarchy of needs, I will continue up the pyramid  (see below) and discuss some ways that the basic need of safety is  met on the ship.  The safety and security of all staff (as well as sea animals we encounter) are top priority on the Oscar Dyson.   There are constant reminders of  this priority during ship life.

A Version of Maslow's Hierarchy of Needs
A Version of Maslow’s Hierarchy of Needs

Safety Drills

On the first day of our travel,  before the Oscar Dyson was far from port at Kodiak,  we had three drills.  The fire drill and man overboard drill required me to report to the conference room and meet up with the rest of the science team.  Patrick, the lead scientist, then reported that we (the scientist team) were all accounted for.  The crew had more complex tasks of deploying a small boat and retrieving “the man overboard”.

The other drill was the abandon ship drill.  On the ship, every person is assigned to a life boat (mine is Lifeboat 1).  When the drill commenced, I reported to my muster, the portside of the trawl deck, with survival gear:  jacket, hat, survival suit and life preserver.  We will have drills weekly at anytime.

Abandon Ship Crew Assignments
Abandon Ship Crew Assignments

Safety Gear
When working in the lab, the scientists wear orange slickers, boots, and gloves, not only to keep clean, but to protect us from anything that might be dangerous (fish spines, jellyfish tentacles, and so on).  When on deck, we must wear hardhats (to protect from falling objects from the crane or trawl) and life preservers like the rest of the crew.

Gloves, a Must in Fish Lab!
Gloves, a Must in Fish Lab!

Water Tight Doors
Watertight doors are special types of doors found on the ship which prevent the flow of water from one compartment to other during flooding or accidents. These doors are used onboard in areas, such as the engine room compartment,  science and acoustics labs, and control bridge, where chances of flooding are high.

Water Tight Door on Bridge
Water Tight Door on Bridge

These are just a few examples of how safety is emphasized on the ship.  There are reminders in one’s line of vision constantly.

Safety, Everyone's Responsibility
Safety, Everyone’s Responsibility

Did You Know?

There are various seafarer or crew positions on the Oscar Dyson.  A ship’s crew can generally be divided into three main categories: the deck department, the engineering department, and the steward department.  Rob and Greg are members of the deck department; both men hold Merchant Mariner Credentials as “Able Bodied Seamen” or ABS.  Rob is from Boston, Massachusetts and went to school for seamanship in Fairhaven, MA.  He considers his NOAA position as a good job with a good income, but his main profession is lobstering which he does on the open sea when he is not working for NOAA.  Rob says, “The ocean is in my blood” and always wanted to work on it.   Greg, on the other hand, chose to be a Merchant Mariner after a voyage at sea.  He moved to Texas from Louisiana in his 20’s, went fishing for the first time, and got seasick.  He considered battling seasickness a challenge, and thus pursing seamanship as a career.  In his free time he is a free-lance photographer and journalist.  Below are some pictures of Greg and Rob on the job.  Notice they are always wearing their safety gear.

Greg and Rob Bringing in the Trawling Net
Greg and Rob Bringing in the Trawling Net

Greg and Rob, Preparing for a Camera Drop
Greg and Rob, Preparing for a Camera Drop

Something to Think About: 

Since I will begin teaching Zoology later in August, I have decided to highlight some of the animals that the scientist team has found in our trawls.  Today’s feature will be one of the simplest multicellular animal families, the Porifera.  Porifera is a word formed from combining the Latin words porus which means “passage-way” and fera meaning “bearing.”  Porifera, commonly referred to as sponges, have tiny pores in their outer walls that filter water to get nutrients.  

Various Porifera (Sponges) from a Bottom Trawl
Various Porifera (Sponges) from a Bottom Trawl

Teacher (me) Demonstrating How Water Flows out the Osculum (opening) of a Poriferan
Teacher (me) Demonstrating How Water Flows out the Osculum (opening) of a Poriferan

To learn more about the Porifera Family, click the Porifera on the picture below, and stay tuned for further exploration of this animal Tree of Life.

Tree of Life: Can you spot the Poriferan?
Tree of Life: Can you spot the Poriferan?

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Kathleen Harrison: Finding Fish, July 12, 2011

NOAA Teacher at Sea
Kathleen Harrison
Aboard NOAA Ship  Oscar Dyson
July 4 — 22, 2011

Location:  Gulf of Alaska
Mission:  Walleye Pollock Survey
Date: July 12, 2011

Weather Data from the Bridge
Air Temperature:  10.15° C, Sea Water Temperature:  7.6° C
True Wind Speed:  12.26 knots, True Wind Direction:  191.38°
Very foggy, visibility < 1/4 mile
Door open on bridge to hear other fog horns
Latitude:  56.07° N, Longitude:  158.08° W
Ship Heading:  24°, Ship Speed:  11.7 knots

Science and Technology Log:  Finding Fish

In a previous log, I talked about using nautical charts and trawling as 2 methods used in calculating the biomass of Walleye Pollock in the Gulf of Alaska.  Finding the fish to catch is tricky business in the ocean, they don’t usually come up to the surface and say hi.  The NOAA scientists working on the Walleye Pollock Survey spend a lot of time looking for fish, so that their trawling efforts won’t be wasted (that is the general idea, anyway).  How do you look for fish in the ocean?  With acoustics, of course, another method used in calculating biomass.

Acoustics is the use of sound, which will travel through the water, and bounce off of objects that it hits.  There is Simrad ER60 echosounder  that operates 5 transducers mounted on the center board under the ship, and it continuously sends out sound waves.

multibeam sonar mapping the ocean floor
The Simrad ER60 echosounder sends sound directly under the ship, finding fish anywhere in the water column.

In the Acoustics Lab of the Oscar Dyson, the data from the multi-beam echosounder is being studied all of the time.  The sound waves leave the device, travel down, hit the swim bladder in a fish (the fish doesn’t even know), and reflect back to the ship.  The time it takes for the sound to return is used to calculate the distance down, and a computer generated picture called an echogram is produced.

echogram shows surface, fish, and bottom
The echogram shows plankton at the surface in blue/green, fish near the bottom as red/brown spots, and the ocean floor as a red/brown line.

The echogram tells the scientists several things.  The surface of the water is shown, with surface dwelling organisms such as krill, phytoplankton, zooplankton, and juvenile fish.  The fish that are mid-water are shown as well, showing up as red or blue dashes or blobs.  This is where the Pollock usually are.  Some fish are bottom feeders, and the red and blue dashes on the bottom represent those.  The ocean floor is also shown, which is very important when choosing which type of trawl to use.   If the bottom is flat, the Poly Nor’Easter could be used to capture to fish on the bottom.  The Aleutian Wing Trawl might be used in mid water if the bottom is rocky and irregular.

Now, looking at the fish from the surface is nice, but wouldn’t it be better to see them close up?  Of course!  The scientists have another tool at their disposal, and no, it isn’t me diving down to the fish (brrr).  This tool is called a Drop Target Strength, or DTS.

echosounder can be dropped into water
The Drop Target Strength (DTS) can be lowered into the water, and get closer to the fish. The information is fed into the computer by a water proof cable.

About once a day, or every other day, the DTS is lowered over the side, and it starts sending out sound waves (3 pings/second), just like the echosounder mounted on the ship.  The advantage with the DTS, though, is that it is closer to the fish, giving a more detailed and accurate picture.  Individual fish can be sighted.  Taking a picture of a fish is kind of like taking a picture of a toddler, they don’t hold still very well.  So, a count of the fish on the echogram might not be exact.  Also, they might change the angle of their body, making the sound wave reflect off their swim bladder at a different angle.  The colors on the echogram are significant:  brown and red mean a strong signal, yellow is medium, and green and blue indicate a weak signal.

echogram shows individual fish
Studying the echogram from the DTS gives scientists a better picture of where the fish are. Each individual wavy line is probably a separate fish.

The scientists will study the echograms to determine where the fish are, and make a decision to fish or not.  Once fishing begins, they will move from the acoustics lab to the bridge, and study the echograms there.  An estimate of how many fish are in the net is made, and then the scientists will ask the crew to “haul back” the net.   (I am learning a whole new language!)  Then, things get very busy as we head to the fish lab to process the fish.

scientists at their desks in the acoustics lab
Here are the NOAA scientists that I am privileged to work with on the Oscar Dyson: (left to right) Darin Jones, Fish Biologist, Denise McKelvey, Fish Biologist, Neal Williamson, Chief Scientist.

New species seen:

Giant Pacific Octopus (juvenile, 1 cm)

Opalescent Squid

Chinook (King) Salmon

Egg yolk jelly fish

Sculpin (juvenile)

North Pacific sea nettle

Spud sponge

tiny squid, only 2 cm long
These are juvenile squid, about 2 cm long. They are nearly transparent.

giant pacific octopus, juvenile, only 1 cm
This is a juvenile Giant Pacific Octopus, only 1 cm wide, complete with 2 huge eyes, and 8 perfect legs.

Personal Log

My days have developed a routine now:  wake at 3:30 am (ugh), start my shift in the acoustics lab about 4:00, breakfast at 7:30, lunch at 11:30, end my shift at 4:00 pm, dinner at 5:30, shower, in bed by 8:00.

my window and life boats
See the orange life saving ring? My window is just to the right of the ring. The 3 white canisters on the back wall hold life rafts that inflate upon release of the canister.

In between these times, I work on my Teacher at Sea log, post pictures on Facebook, read and answer e-mail, visit the bridge and ask lots of questions, and of course, process fish whenever there is a trawl (very fun).  Today marks the halfway point of our cruise!  The ship is quieter than I thought, even though there are 35 people on board, the most that I ever see might be 10 during mealtimes.  There is constant background noise of the ship’s engines, waves hitting the bow of the ship, creaks and groans of the furniture as the ship rolls, but I am used to it now, and hardly notice it.  I am thankful for the calm weather that we have had so far.

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Melinda Storey, June 25, 2010

NOAA Teacher at Sea
Melinda Storey
Onboard NOAA Ship Pisces
June 14 – July 2, 2010

Mission: SEAMAP Reef Fish Survey
Geographical Area of Cruise: Gulf of Mexico
Date: Friday, June 25, 2010

Weather Data from the Bridge
Time: 1000 hours (10 am)
Position: latitude = 27°53.9 N longitude = 093º 51.1 W
Present Weather: 5/8 cloudy (cumulonimbus/cumulus clouds)
Visibility: 10 nautical miles
Wind Direction: E Wind Speed: 4 knots
Wave Height: 1 foot
Sea Water Temp: 30.5°C
Air Temperature: dry bulb = 29.2°C, wet bulb = 26.3°C

Science and Technology Log

Video from the Camera Array
Video from the Camera Array

Echosounder
Echosounder

The technology on this ship is amazing! The picture on the left is video of what the camera array filmed yesterday. The fish just swim around and sometimes they even come right up to the camera like they are “kissing” it. Then they back away and swim off. It’s beautiful to watch. The picture on the right is the EK60 Echo Sounder. The red line that you see shows the bottom of the seafloor. The blue above the red line is the water itself and the white specks that you see are fish. The most recent reading is located on the right side of the screen. The echo sounder sends a “ping” to the computer and that “ping” is a fish. Sometimes we can see definite shark outlines in the images below our ship. If you look at the bottom right hand corner of the echo sounder photo, you will see a large white speck along the red line. This indicates a large fish (possibly a shark) trolling the bottom of the ocean. When we came upon the dead sperm whale, the Electronics Technician (ET) came to the lab and told us there were a lot of “large fish,” most likely Mahi Mahi or even sharks, swimming under the ship.
The Pisces would not be able to operate without the engineers who make sure that everything onboard is functioning properly, including the 4 massive diesel generators that power the ship, the freshwater generators that convert seawater into fresh drinking water, and the hydraulics that power the cranes to lift the cameras in and out of the water. Chief Engineer Garet Urban leads the team of engineers, oilers, and electrical experts who take care of all the mechanical issues on board the ship.

First Engineer, Brent Jones, took us on a tour of the very impressive engine room on the lower deck of the Pisces. He showed us the incinerator which burns all the trash, oil filters, and other waste at a temperature of 1200°C (2192°F). Paper, plastic, and aluminum is brought back to shore and recycled. Before entering the engine room, we were told to put in earplugs because the sound can damage your eardrums. In addition to not being able to hear a thing inside the engine room, the heat is incredible! The engineers need to be careful to stay hydrated while working in these conditions.

Engine room
Engine room

Diesel Generators
Diesel Generators

The Pisces is powered by 4 diesel fuel generators which generate electricity that drives two large electric motors. The photo above on the right shows one of the generators in yellow. The engineers are constantly monitoring the mechanics of the ship to make sure everyone on board has a safe and productive voyage while conducting scientific research on board.

Personal Log

All this technology on board makes me drool! The Pisces is certainly a beauty of the NOAA fleet. Each morning Chris Gledhill, our fishery biologist, looks at the video from the camera array and I’m hanging just over his shoulder watching all the coral and fish. It’s really interesting to see the fish swim by the camera and now I can even identify some of them. I never knew there was a type of coral called “wire coral.” It looks like curly-cue wire used in floral arrangements. One of our deck hands caught some on his fishing pole one night and when I held it, the coral moved! Wire coral is a living creature so, of course it moved!

What I thought was really funny was watching a big grouper swim by the camera and then we caught it on the Bandit Reel. Nothing like seeing your fish before you catch it! Here you can see Paul Felts and me holding the 21 pound grouper.

Big Grouper
Big Grouper

Big Grouper caught
Big Grouper caught

Just like school, the Pisces has drills – fire drills, man overboard drills, and abandon ship drills. It’s always good to be prepared. When we have an abandoned ship drill we have to put on our “Gumby Suit.” This survival suit would protect us by keeping us afloat and warm if we really had to go into the water. The Gumby Suit is not exactly the latest fashion but I would certainly want it if I have to abandon ship.

Gumby Suit
Gumby Suit

Teacher at Sea in their Gumby suits
Teacher at Sea in their Gumby suits

The day after this Abandon Ship drill, we had a REAL fire drill. Over the PA system we heard, “This is not a drill. This is not a drill.” The forward bow thruster was smoking. We “mustered,” or gathered, on the second deck, but when we got there we could really smell smoke. So, we were sent down to the main deck for precaution. Fortunately, we have an outstanding crew who fixed the problem immediately.

New Term/Vocabulary

Muster – to gather

“Something to Think About”

While on the bridge last night, I heard on the radio another ship broadcast they were “taking on water.” What would you do if you were on a boat in the Gulf and it suddenly started taking on water?

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Jeannine Foucault, November 15, 2009

NOAA Teacher at Sea
Jeannine Foucault
Onboard NOAA Ship Pisces
November 7 – 19, 2009

Mission: Ecosystem Survey
Geographic Region: Southeast U.S.
Date: November 15, 2009

Crew in safety gear
Crew in safety gear

Science Log

If you have been using the ship tracker you would be able to follow that last night we cruised around the bottom tip of Florida out of the Gulf of Mexico into the Atlantic Ocean. The waters were a bit rough with wind gusts up to 40 knots. It was a rocky night. Not to mention a very sleepless night with the greenish way I was feeling :)! Needless to say I haven’t had much to eat today except for some dry Captain Crunch cereal. The head chef on the mess deck suggested it would be a good stomach filler. We will see and I will let you know!

Once I got my sea legs back I was anxious to see what everyone else was doing. The crew as well as the scientists were very busy; therefore, I stayed pretty much out of their way for a while. The crew was trying to get us an arrival in Jacksonville, FL and the tech crew was busy trying to get us online since the internet signal went down. Talking to the captain he says that with a new boat there are always kinks that have to be ironed out …that’s why we call these sea trials.

Lab equipment aboard the ship
Lab equipment aboard the ship

The mammal scientists were working on their equipment trying to get their equipment calibrated correctly. They explained to me that PISCES is equiped with many sensors (transducers) and these sensors are connected to different pieces of equipment to help pickup the ocean ecosystem. For instance, the mammal scientists are using the echo sensors on the computers (see below) that operates seven echo sound frequencies. Then the scientists can use this realtime data for analysis of targets, concentrations, the layers of ocean, etc. This provides a broad scope of marine acoustic survey from plankton to large schools of fish.

While I was on deck watching the waves I noticed a bunch of birds that flew into the water but never came up. I watched a while longer and again, but this time these creatures came up from the water and flew across it into a huge dive back into the ocean. These were not birds…..these were ‘flying fish’! They are C.melanurus common to the Atlantic. They are silly little fish always flying from a predator under water.

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Chris Imhof, November 15, 2009

NOAA Teacher at Sea
Chris Imhof
Onboard NOAA Ship Pisces
November 7 – 19, 2009

Mission: Coral Survey
Geographic Region: Southeast U.S.
Date: November 15, 2009

Science Log

Rough winds and big choppy waves coming around the Keys and into the Gulf Stream last night kept many awake and few of us with a taste of sea sickness. We make port in Jacksonville tonight and take on the ROV and more scientists. While making the first leg of this voyage it has been good to get to meet most of the crew and learn what they do and where they work on the Pisces; these include NOAA engineers, electrical and computer technicians, deck crew, stewards, and the NOAA Core officers. Since this is a maiden voyage, many of these people have worked on other NOAA ships – bringing their expertise and skills to get the Pisces up and working smoothly. Many of this crew will stay with the Pisces – operating the ship for NOAA scientists who come aboard to run experiments or do research in the months to come.

When I boarded the Pisces last Wednesday, the mammal scientists Tony Martinez and Lance Garrison were already on board testing equipment for an expedition this coming January – for detecting concentrations of sperm whale prey – from small fish to squid – acoustically and visually. Two pieces of technology they use are the EK60 Echosounder and ME70 Splitbeam:

1) The EK60 Simrad Echo-Sounder: This piece of technology uses a devices called a transducers that are located on the bottom of the Pisces to detect organisms. The Echo-Sounder operates on 4 frequencies – split beams of 200 and 120 khz (kilohertz) for shallow water detection – giving good data on zooplankton and small schools of fish, and the 18 and 38 khz frequencies which can detect fish, mammals and squid much deeper. The transducers issue a ping at each frequency every .5 seconds which bounce back creating a picture or vertical scatter. The scatter shown is a reflective signature – which the scientist use to identify what is below.

2) The ME70:  The ME70 is brand new technology that uses a single high frequency – but based on amplitude reverberates from 80 transducers in a fan or swath -like shining a spot light down the water column. This gives another kind of visual image of what is below – especially the characteristics of the concentrations of zooplankton and nekton or schools of fish.

Tools and technology like this help scientists conduct surveys of marine species in deep and shallow waters, they can improve the way we estimate fish stocks – and the more it is used and tested can be a passive way to identify species in their habitats through their acoustic signatures.

An interesting aspect of this technology is the growing study of “swarm behavior” – understanding why schools of fish glide in precise synchronous movement. This field of study is becoming more important as we learn that self-organizing coordinated systems like schools of fish are extremely resilient and efficient. Mammal studies conducted by Tony and Lance aboard the Pisces may have larger implications in the future when looking at the behavior of crowds, or traffic on a highway, or how people move in a work place.

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Christine Hedge, September 1, 2009

NOAA Teacher at Sea
Christine Hedge
Onboard USCGC Healy
August 7 – September 16, 2009 

Mission: U.S.-Canada 2009 Arctic Seafloor Continental Shelf Survey
Location: Beaufort Sea, north of the arctic circle
Date: September 1, 2009

The path of the Healy through the ice with the Louis S. St. Laurent from Canada following (See it way in the distance?)
The path of the Healy through the ice with the Louis S. St. Laurent from Canada following (See it way in the distance?)

Weather Data from the Bridge 
Latitude: 800 26’N
Longitude: 1370 16’W
Temperature: 200 

Science and Technology Log 

Why Are Two Icebreakers Traveling Together? 

All of the countries that have a coastline on the Arctic Ocean are trying to collect data to determine where their extended continental shelf (ECS) ends. One of the types of data needed is called seismic data.  Collecting this information involves towing a long (a kilometer or more) streamer behind the ship. It is difficult to do this well in ice-covered water.  So, the Canadians and the Americans are collecting data together. One icebreaker leads and breaks a path for the second following with the seismic streamer being towed behind.  For most of our trip together, the Healy has broken ice for the Louis S. St. Laurent. We are both collecting data – just different types with different instruments.

FOR MY STUDENTS: Can you name all the countries that have coastlines on the Arctic Ocean? Of which country is Greenland part? 

Why Do We Care Where Our Extended Continental Shelf Is? 

Close-up of the Louis S. St. Laurent collecting data behind the Healy
Close-up of the Louis S. St. Laurent collecting data behind the Healy

The oceans and ocean floors are rich with natural resources.  Some countries obtain much of their wealth from mining the oceans, drilling for oil or gas in the oceans, or from fish or shellfish obtained from the oceans.  Currently, a nation has the right to explore for and harvest all resources in the water and everything on or below the seafloor for 200 nautical miles beyond its shoreline. One nation can allow other nations to use its waters or charge oil companies for the right to drill in its seafloor and thus make money. But what if we could use resources beyond that 200-mile limit? That would add to a country’s wealth. If a country can show with scientific data that the continental shelf extends beyond those 200 miles they can extend their rights over:

 

1) The non-living resources of the seabed and subsoil (minerals, oil, gas)

2) The living resources that are attached to the seabed (clams, corals, scallops ) An extended continental shelf means a nation has rights to more natural resources.

FOR MY STUDENTS: Look at a map of the oceans. Can you find the continental shelf marked on the Atlantic coast of the United States? What types of resources can you think of that we get from the ocean and the seafloor? 

Where Exactly Is the Healy Going? 

The red line shows where the Healy has been. The yellow waypoints show where we might be after September 1, 2009.
The red line shows where the Healy has been. The yellow waypoints show where we might be after September 1, 2009.

Our trail looks random to the untrained eye but it does have a purpose.  We have been helping the Louis get good measurements of the thickness of the sediments on the seafloor.  You see there are certain features of the seafloor that help a nation identify its ECS.  One is related to depth. Another is related to the thickness of the underlying sediments.  Another is related to the place where the continental slope ends (the foot of the slope).  We have been following a path that takes us to the 2500-meter contour (where the ocean is 2500 meters deep) and following a path to measure the thickness of the sediment in the Canada Basin.  I was surprised to think that there was thick sediment on the seafloor in this area.  But, the Arctic is a unique ocean because continents surround it. It is more like a bowl surrounded by land.  As rivers have flowed into the Arctic over millions of years – layers and layers of sediment have covered the Canadian Basin.

FOR MY STUDENTS: Look at your maps again.  Find rivers, bays, fjords, that flow into the Arctic Ocean.  For More Information About The Extended Continental Shelf

Personal Log 

Erin Clark, Canadian Ice Services Specialist has been working with us on the Healy.
Erin Clark, Canadian Ice Services Specialist has been working with us on the Healy.

The U.S and Canada have been sharing personnel as well as sharing a science mission.  Coast Guard personnel and science party personnel have been traveling between the two ships via helicopter to share their expertise.  As the Canadian visitors come through our science lab and eat meals with us – we have had plenty of time to discuss science and everyday life. There has also been a longer-term exchange of personnel.  A scientist from the United States Geological Survey (USGS) has been sailing on the Louis since they left Kugluktuk, Northwest Territories. Dr. Deborah Hutchinson is on the Louis to provide USGS input to scientific decisions made during the cruise.

My roommate, Erin Clark, is a Canadian Ice Services Specialist.  Erin hails from Toronto, Ontario and is staying on the Healy to exchange expertise with the American ice analysts.  It has been interesting getting to know Erin and hearing the story of her career path.  She was one of those kids in school who just couldn’t sit still in a structured classroom environment.  Erin is a visual learner – and often had a hard time proving to her professors that she understood the material as she worked on her degree in Geography.  Where other students used multi-step equations, Erin used diagrams and often didn’t “show her work”.  NOTE TO STUDENTS: Do you know how you learn best?  What is your learning style?

Matthew Vaughan a Canadian geology student from Dalhousie University shows us pictures of the seismic gear on the Louis
Matthew Vaughan a Canadian geology student from Dalhousie University shows us pictures of the seismic gear on the Louis

Erin was lucky enough to have instructors that worked with her and now she is one of about 20 Marine Services Field Ice Observers in Canada. Luckily, she has found a career that offers lots of opportunities to move around. Some of her time is spent analyzing satellite photos of ice on a computer screen, some ice observing from a ship, and some ice observing on helicopter reconnaissance trips.  She communicates what she observes about ice conditions to ships; helping them to navigate safely in ice-covered waters.

FOR MY STUDENTS: What kind of skills do you think an Ice Specialist would need to succeed in their career? 

Posted on

Christine Hedge, August 26, 2009

NOAA Teacher at Sea
Christine Hedge
Onboard USCGC Healy
August 7 – September 16, 2009 

Mission: U.S.-Canada 2009 Arctic Seafloor Continental Shelf Survey
Location: Beaufort Sea, north of the arctic circle
Date: August 26, 2009

Science and Technology Log 

This is what we see in the Science Lab of the Healy before the data is processed. It is like a cross-section through the top 50-100 meters of the sea floor. Here you can see it was flat and then climbed uphill. The numbers represent round trip travel time in seconds.
This is what we see in the Science Lab of the Healy before the data is processed. It is like a cross-section through the top 50-100 meters of the sea floor. Here you can see it was flat and then climbed uphill. The numbers represent round trip travel time in seconds.

Is There a Bird in My Room? 

When I first got on the Healy, I thought there was a bird in my room.  Then I realized the chirp that I kept hearing every 9 seconds or so was not just in my room.  It got louder as I went down the ladders to the deepest part of the ship near the laundry. I found out that this chirp is the sound transmitted by the subbottom profiling system.  This instrument is being used on the Healy to collect data about the depth of the water and the nature of the sea floor. These subbottom profiler transducers are mounted on the hull of the ship. The “chirp” sound reflects (echos) off the bottom of the ocean and also reveals the sediment layers below the bottom.  This is one of the systems I watch on a computer screen when I am working.

Using Sound as a Tool to See Inside the Earth 

Sound is an amazing tool in the hands of a geophysicist, who is a person who studies the physics of the earth. The subbottom profiler uses a low frequency sound. Low frequency will penetrate further into the earth than the higher frequencies used by echosounders. This helps scientists to “see” about 50 meters below the surface, depending on the type of sediment (clay, sand, etc).  By looking at how the sound waves are reflected back to the ship, scientists can see layering of sediments, infer sediment type (REMEMBER SAND, SILT, CLAY???), and sometimes see evidence of channels under the sea floor.

The subbottom profiler data is processed and an image is generated for scientists to analyze. This is an image from the 2005 Healy trip to the Arctic. You can see the types of features the sound waves can “see” for us.
The subbottom profiler data is processed and an image is generated for scientists to analyze. This is an image from the 2005 Healy trip to the Arctic. You can see the types of features the sound waves can “see” for us.

FOR MY STUDENTS:  DO YOU REMEMBER STUDYING SOUND IN 6TH GRADE?  WHAT DOES FREQUENCY REFER TO?  

These pictures appear on many doors of the Healy
These pictures appear on many doors of the Healy

Why Is This Important? 

Geologically speaking, the Arctic Basin is poorly understood. We are not sure how some of the major features formed or even where the plate boundaries are.  When you look at maps of the tectonic plates, you might notice that they are not clearly marked in the Arctic. Understanding how the sea floor is shaped and what lies beneath will give us clues to understand the history of the Arctic Basin. From a practical standpoint, geology can tell us where important natural resources might occur. When companies are searching for natural gas or petroleum, they are using clues from the geology of the sea floor to decide where to look.

Personal Log 

More About Sound – From A Personal Perspective 

Lieutenant Commander Doug Petrusa wearing protective headset
Lieutenant Commander Doug Petrusa wearing protective headset

As far as I can tell there is no place on a ship where it is completely silent.  There are fans, air compressors, engines, doors opening and closing and of course on this ship ice breaking and chirping.  There are some places on the ship where we are warned to use ear protection because the machine noise could, over long periods, cause hearing loss.  Many doors on the ship have pictures reminding us to wear ear protection in certain areas to protect our hearing.   The crew spends time working in areas with high intensity noise – so they are often seen wearing protective headsets.

In addition, all over the ship, there are boxes of earplugs. These are available for people to use whenever they need them.  My first week, I slept with earplugs every night.  The constant chirping, the sound of the engines and the doors opening and closing were more than I could handle. I thought I would need to use earplugs for the entire journey. Now, I am sleeping like a baby even with the additional sound of us plowing through ice. I guess the human body can get used to just about anything.

Earplugs are found near every doorway that leads into an area with dangerous noise levels.
Earplugs are found near every doorway that leads into an area with dangerous noise levels.

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Christine Hedge, August 25, 2009

NOAA Teacher at Sea
Christine Hedge
Onboard USCGC Healy
August 7 – September 16, 2009 

Mission: U.S.-Canada 2009 Arctic Seafloor Continental Shelf Survey
Location: Beaufort Sea, north of the arctic circle
Date: August 25, 2009

Weather Data from the Bridge 
Temperature: 30.150F
Latitude: 81.310 N
Longitude: 134.280W

Science and Technology Log 

This multibeam image of the new seamount is what I saw in the Science Lab.
This multibeam image of the new seamount is what I saw in the Science Lab.

A Day of Discovery… 

Today, our planned route took us near an unmapped feature on the sea floor.  A 2002 Russian contour map showed a single contour (a bump in the middle of a flat plain) at 3600 meters.  This single contour line also appeared on the IBCAO (International Bathymetric Chart of the Arctic Ocean) map.  We were so close that we decided to take a slight detour and see if there really was a bump on this flat, featureless stretch of sea floor. 

The contour was labeled 3600 meters and the sea floor in the area averaged about 3800 meters so a 200 meter bump was what the map suggested.  As the Healy traveled over the area we found much more than a bump!  The feature slowly unfolded before our eyes on the computer screen.  It got taller and taller and excitement grew as people realized this might be over 1000 meters tall.  If a feature is 1000 meters or more, it is considered a seamount (underwater mountain) and can be named.  Finally, the picture was complete, the data was processed, and a new seamount was discovered. The height is approximately 1,100 meters and the location is 81.31.57N and 134.28.80W.

The colors on this 3-D image of the newly discovered seamount indicate depth.
The colors on this 3-D image of the newly discovered seamount indicate depth.

Why Isn’t the Arctic Mapped? 

Some areas of the sea floor have been mapped and charted over and over again with each improvement in our bathymetric technology.  Areas with lots of ship traffic such as San Francisco Bay or Chesapeake Bay need to have excellent bathymetric charts, which show depth of the water, and any features on the sea floor that might cause damage to a ship.  But in the Arctic Ocean, there isn’t much ship traffic and it is a difficult place to collect bathymetric data because of all the ice. Therefore, in some areas the maps are based on very sparse soundings from lots of different sources. Remember, older maps are often based on data that was collected before multibeam  echosounders and GPS navigation – new technology means more precise data!  

Personal Log 

This is the IBCAO. (International Bathymetric chart of the Arctic Ocean) It is a great resource for ships exploring the Arctic Basin.
This is the IBCAO. (International Bathymetric chart of the Arctic Ocean) It is a great resource for ships exploring the Arctic Basin.

It is still very foggy. We are about 625 miles north of Alaska and plowing through ice that is 1-2 meters thick.  This time of year it is the melt season.  Increased evaporation means more water in the atmosphere and more fog.  Even though we are usually in water that is 90% covered by ice (REMEMBER 9/10 ice cover?) we rarely have to back and ram to get through.  It is noisier lately and the chunks of ice that pop up beside the ship are more interesting to look at.  There are blue stripes, brown patches of algae and usually a thin layer of snow on top.

I cannot send a current sound file because of our limited bandwidth on the Healy. When we are this far north it is difficult to get Internet access. But, if you would like to hear what it sounds like when the Healy is breaking ice, click on this link  from a past trip through Arctic sea ice.

Sea Ice at 810N after the Healy has broken through
Sea Ice after the Healy has broken through

Posted on

Christine Hedge, August 20, 2009

NOAA Teacher at Sea
Christine Hedge
Onboard USCGC Healy
August 7 – September 16, 2009 

Mission: U.S.-Canada 2009 Arctic Seafloor Continental Shelf Survey
Location: Beaufort Sea, north of the arctic circle
Date: August 20, 2009

Weather Data from the Bridge  
Lat: 80.570 N
Long: 151.320 W
Air Temp: 29.210 F

Science and Technology Log 

The science computer lab is where the data is observed. Processors clean the data of all the extraneous noise and spikes. Not every beam is returned and some take a bad bounce off a fish, chunk of ice or a bubble.
The science computer lab is where the data is observed. Processors clean the data of all the extraneous noise and spikes. Not every beam is returned and some take a bad bounce off a fish, chunk of ice or a bubble.

The Healy is collecting bathymetric data on this trip.  Bathymetric data will tell us how deep the ocean is and what the terrain of the ocean floor is like.  Less than 6% of the floor of the Arctic Ocean has been mapped.  So, this data will help us to learn about some places for the very first time.  The word bathymetry comes from the Greek – bathy= deep and metry = to measure.

NOTE TO STUDENTS: If you learn Latin/Greek word parts you can understand almost any word! 

How Do We Collect This Data? 

There are two main devices the Healy is using to measure the depth to the seafloor.  One is called the multibeam echosounder. It sends a beam of sound, which reflects off the bottom and sends back up to 121 beams to a receiver. By measuring the time it takes for the sound to return the multibeam can accurately map the surface of the sea floor.  This allows the multibeam to “see” a wide swath of seafloor – kilometers wide.  The other device is bouncing a single beam off the bottom and “seeing” a profile of that spot. This one is called a single beam echosounder or sub-bottom profiler. The single beam actually penetrates the sea floor to show a cross-section of the layers of sediment. Both are mounted on the hull of the ship and send their data and images to computers in the science lab.

What Does Mrs. Hedge Do? 

This screen shows the multibeam bathymetry data. Depth is measured over a swath about 8 kilometers wide on this particular screen. Purple is the deepest (3850 m) and orange is the most shallow (3000 m). You can see that for most of this trip we were on flat abyssal plain and then we hit a little bump on the sea floor about 450 meters tall.
This screen shows the multibeam bathymetry data. Depth is measured over a swath about 8 kilometers wide on this particular screen. Purple is the deepest (3850 m) and orange is the most shallow (3000 m). You can see that for most of this trip we were on flat abyssal plain and then we hit a little bump on the sea floor about 450 meters tall.

The science crew takes turns “standing watch”. We have 3 teams; each watches the computers that display the bathymetry data for an 8-hour shift. My watch is from 8 am until 4 pm.  We need to look at how many beams are being received and sometimes make adjustments.  Traveling through heavy ice makes data collection challenging. We also need to “log” or record anything that might impact the data collection such the ship turning, stopping, heavy ice, or a change in speed. When we are going over an interesting feature on the seafloor, our job is engaging. When the seafloor is flat, the 8-hour shift can seem pretty long!

How Did People Do This Before Computers? 

Until the 1930’s, the depth of the ocean was taken by lowering a lead weight on a heavy rope over the side of a boat and measuring how much rope it took until the weight hit the bottom. This was called a lead line.  Then the boat would move and do this again, over and over.

Another bear was spotted from the Healy. Photo Pat Kelley.
Another bear was spotted from the Healy. Photo Pat Kelley.

This method was very time consuming because it only measured depth at one point in time.    Between soundings, people would just infer what the depth was.  Using sound to measure depth is a huge improvement compared to soundings with a weighted rope.  For example, in 100 meters of water, with a lead line 10 soundings per hour could be obtained.  With multibeam at the same depth, 1,500,000 soundings can be obtained per hour.  Mapping the ocean floor has become much more accurate and precise.

FOR MY STUDENTS: Can you think of other areas of science where improvements in technology lead to huge improvements and new discoveries? 

Personal Log 

When a polar bear is spotted, the deck fills with hopeful observers.
When a polar bear is spotted, the deck fills with hopeful observers.

Last night, there was an announcement right after I went to bed that polar bears had been spotted.  I threw on some clothes and ran outside.  There was a female and cub 2 kilometers away.  With binoculars, I could see them pretty well.  The adult kept turning around and looking at the cub over her shoulder. I suspect, the cub was being told to hurry up!  When a bear is spotted, the deck of the ship fills up with hopeful observers no matter what time of day it is.

FOR MY STUDENTS: I heard that the old polar bear at the Indianapolis Zoo died recently. Will there still be a polar bear exhibit at the zoo?  What are the plans for the future? 

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Megan Woodward, July 10, 2009

NOAA Teacher at Sea
Megan Woodward 
Onboard NOAA Ship Oscar Dyson
July 1 – 18, 2009

Mission: Bering Sea Acoustic Trawl Survey
Geographical Area: Bering Sea/Dutch Harbor
Date: Tuesday, July 10, 2009

The pollock are carefully loaded onto the table.
The pollock are carefully loaded onto the table.

Weather/Location 
Position: N 56.30.202; W 172.34.37
Air Temp: 7.4 (deg C)
Water Temp: 7.4 (deg C)
Wind Speed: 19 knots
Weather: Overcast

Science and Technology 

Once the fish are onboard a rigorous data collection process begins.  All of the data collected are recorded via instruments linked to a computer network in the fish lab.  Below is a series of photos showing the process used in the fish lab to collect valuable data.

Once the fish are on the table, we carefully look through the fish for any species other than pollock caught in the trawl.  These non-pollock species are sorted into bins and accounted for. The fish are weighed one basket full at a time as they reach the end of the conveyor belt.  Initially, we take a count of how many fish fill one basket.  There is a scale connected to a computer program that records the basket’s weight.

The sorting begins. The pollock are sorted between male and female.
The sorting begins. The pollock are sorted between male and female.

After weighing the pollock, we move on to sorting a sample of approximately 300 fish by sex.  To find the sex of a fish we cut open its belly and look for either male or female reproductive organs. The sexed fish are then placed in the appropriate bin. Next, each pollock from the male/female sort is measured in centimeters.  We use a measuring board linked to a computer that records the size of each fish. There is a small tool in my hand that gets placed at the “v” of the fish tail.  Sensors on the board detect the placement of the measuring wand, and send a length measurement to the computer so it can be recorded.  This program also keeps track of how many fish we measure, so we get an accurate sample count.

The stomach of a pollock is prepared for preservation.
The stomach of a pollock is prepared for preservation.

Several scientists have asked us to collect pollock for various research projects. One project, designed to study the diet of pollock, requires us to sex, measure, weigh and take the stomach of 20 pollock from each haul. A label with all of the information is placed in a bag with the stomach.  They are placed in a freezer for preservation purposes.

Here I am using the measuring board. The stomach of a pollock is prepared for preservation.
Here I am using the measuring board.

We also use a similar process for scientists examining one-year-old pollock. This study asks for the entire fish to be preserved, not a specific organ. In one 12-hour shift there is a maximum of 3 trawls if fish sign is identified in the acoustics lab. Each trawl takes 2 to 3 hours to process. It’s possible another trawl could happen while finishing up the data collection from the previous haul. This makes for a very busy, fish filled shift.

Personal Log 

I was in charge of weighing the fish!
I was in charge of weighing the fish!

Working in the fish lab has provided for a tremendous amount of new learning to take place. I’ve learned to identify species of fish that mix in with pollock (capelin, flatfish, skate and cod), and have seen several crustaceans and jellyfish, too.  All of the measuring technology has been straight forward and user friendly. Sexing the fish has been the most difficult job, but has become easier with practice. Examining the innards to identify male or female reproductive organs seems nearly impossible in the young fish, and it’s not always clear in the older fish.

Today I was in charge of weighing the fish as they came down the conveyor belt. I was certainly mistaken when I thought it would be a simple task. First off, I had to count the fish as they dropped into the basket at a speed faster than I could count. At the same time I had to control the speed of the belt and open the gate so more fish would move down the line.  When the basket was full, I stopped the belt and placed the full (semi-accurately counted) basket on the scale and waited for the scale’s “steady” signal to come on.  Since the boat is constantly in motion the steady light rapidly blinks on and off. It took me three tries before I managed to get the basket weighed.  Meanwhile the rest of the team patiently waited.  Maybe I’ll give it another try tomorrow.

This average sized skate was flapping his wings making him difficult to hold. Look closely at the fish on the conveyor belt and you will see hermit crabs and seastars.
This average sized skate was flapping his wings making him difficult to hold. Look closely at the fish on the conveyor belt and you will see hermit crabs and seastars.

Basketstars were brought up in a bottom trawl. Hermit crabs and snails were also caught in the bottom trawl.
Basketstars were brought up in a bottom trawl.

Hermit crabs and snails were also caught in the bottom trawl.
Hermit crabs and snails were also caught in the trawl.

Animals Seen 

  • Minke Whale
  • Skate
  • Pacific Cod
  • Tanner Crab
  • Snow Crab
  • Basketstar
  • Sturgeon Poacher
  • Snails
  • Hermit Crabs
  • Arrow Tooth Flounder
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Megan Woodward, July 7, 2009

NOAA Teacher at Sea
Megan Woodward 
Onboard NOAA Ship Oscar Dyson
July 1 – 18, 2009

Mission: Bering Sea Acoustic Trawl Survey
Geographical Area: Bering Sea/Dutch Harbor
Date: Tuesday, July 7, 2009

This map depicts the path the Miller Freeman will take on our cruise.
This map depicts the path the Miller Freeman will
take on our cruise.

Weather/Location 
Position: N 56.18.292; W 171.46372
Air Temp:  7.3 (deg C)
Water Temp:  6.9 (deg C)
Wind Speed: 17 knots
Weather: Overcast

Science and Technology Log 

We are traveling on designated lines in the north/south direction looking for pollock (travel lines are illustrated above). The samples we pull in are compared to the amount of fish found in the same location over 20+ years.  The process used to “go fishing” is not as easy as one might think.  Several things need to align for a successful trawl to take place. As of today, I have been a part of three successful trawls.  Below is an explanation of the fishing process.

  1. The Fisheries Research Biologist and his team recognize a series of acoustic returns as potential pollock schools while sitting in the acoustics lab. Then they decide if the amount of fish being seen is enough to fish on. If yes, go to step 2.
  2.  Next the team questions if the weather conditions are calm enough, are the fish far enough off the bottom of the sea floor, and have we traveled at least 30 miles from our last fishing point.  If conditions are aligned, move to step 3.
  3. The team contacts the bridge to prepare the crew for fishing. The bridge receives the exact location (longitude/latitude) the nets should enter the water for the best possible fishing.  By now we have traveled over the top of the fish we saw on the acoustic screen.  A decision must be made about the best direction to travel so the nets work properly:  Do we flip a u-turn and fish up the line, or do we circle back to where we saw fish and retrace our path on the line? The water’s current and prevailing winds impact how the nets will function, which are some of the deciding factors in choosing the direction we will tow the nets.  Fishing in motion, continue to step 4.
  4.  Up to the wheelhouse. Here the lead fisherman, the ship’s Officer of the Deck (person in charge of driving the ship) and the fisheries team can work together to create the best fishing scenario. The same acoustic information can be viewed in the wheelhouse as in the acoustic lab.  Based on the depth of the acoustic return, the fisheries team can inform the fisherman how far to lower the nets in the water. Keep going to step 5. We almost have fish…we hope!
  5. Once the net is in the water, there are two acoustic screens closely watched. These are pictured below with the explanation of the information received.  The net is continually raised or lowered based on the depth of the return. A trawl lasts for 20 minutes and covers 1 mile on average. The fisheries team is aiming for 300 fish per trawl.  They are careful to not over fish. Almost done, bring the fish aboard.
  6. The final step is bringing the nets back in and unloading the fish.  If all went as planned, the next few hours will be spent in the fish lab collecting information about the sample. Unfortunately the system is not perfect.  It’s possible to bring in a water haul or a stuffed sausage. Neither one is good news.

This is the acoustics lab. The top screens are displayed in the bottom monitors as needed. The top two left monitors show the acoustic return from the 5 frequencies (pings) sent out.
This is the acoustics lab. The top screens are displayed in the bottom monitors as needed. The top two left monitors show the acoustic return from the 5 frequencies (pings) sent out.

Personal Log 

Now that I have participated in three trawls, I’m feeling much more comfortable with the whole fishing process. Rather than looking at the acoustic screens with a puzzled look, I’m able to recognize what the return from a school of pollock looks like. Jellyfish show up on the screen as blue-green clusters, and have been present in the top 40 meters of water the majority of time we’ve been at sea.  I can only imagine how many of those creatures are down there.

There seems to be a bit of humor in all we do at sea.  There are two awards given out based on the hauls we bring in: The water haul and the stuffed sausage awards.  You really don’t want to be the recipient of either one. The water haul award goes to the team that brings in the haul with the least fish (mostly water). This happened yesterday when we attempted to catch pollock close to the surface.  There wasn’t but a single pollock in the net. Of course there were numerous jellyfish.

This is an acoustic screen showing a return typical of pollock. The several clusters with the trail of return on the left are showing a good fishing opportunity. The dark red across the middle of the screen is the sea floor.
This is an acoustic screen showing a return typical
of pollock. The several clusters with the trail of
return on the left are showing a good fishing
opportunity. The dark red across the middle of the screen is the sea floor.

The stuffed sausage is just the opposite of a water haul. As you may have guessed, the stuffed sausage award goes to the team that brings in the most over-stuffed net.  If we were looking to make money off of our catch, this would be considered a success. However, we really only want a sample of about 300 fish. A stuffed sausage means too many fish were brought in.  It is possible to be the “winner” of both awards.

Animals Seen 

  1. Red-legged kittiwake  
  2. Blacklegged kittiwake
  3. Albatross
  4. Fulmar
  5. Fur Seal
  6. Capelin (they smell like cucumber)

This screen shows the return from a signal that sweeps left to right like a pendulum. The bottom of the net is the ½ circle shape. During a trawl you can see if a school of fish enters the net.
This screen shows the return that sweeps left to right like a pendulum. The bottom of the net is the ½ circle shape. During a trawl you can see if a school of fish enters the net.

When the net is in the water, there is return from the top and bottom of the net. This screen shows a vertical return. We can see we are at the correct depth, but maybe we are too far to the left or right.
There is return from the top and bottom of the net. This screen shows a vertical return. We can see we are at the correct depth, but maybe too far to the side.

New Vocabulary 

Acoustic Lab: AKA “The Cave” because there are no windows.  This is where the Fisheries Research Biologist and his team watch the acoustic return monitors.

Bridge/Wheelhouse:  This is where the officer on duty drives the ship using several navigational tools. Named the wheelhouse because the ship’s steering wheel is found here.  The bridge is located on the top level of the ship. The Methot and trawl nets are also operated from the bridge.

Haul:  This is how the fish are referred to when they are caught in the net.  One might ask, “How was the haul?”  “It was a (big haul, small haul, water haul, stuffed sausage).”

Water Haul:  A net lacking fish following a trawl.

Stuffed Sausage: An overstuffed net, too many fish caught.

Hauling in the net
Hauling in the net

This fur seal followed the boat for about 30 minutes while we were trawling for pollock. He was hoping for a free dinner.
This fur seal followed the boat for 30 minutes while we were trawling. He was hoping for a free dinner.

The center bird is a blacklegged kittiwake, identified by the black wing tips, white underwing and the light gray color on its back.
The center bird is a blacklegged kittiwake, identified by the black wing tips, white underwing and the light gray color on its back.

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Megan Woodward, July 5, 2009

NOAA Teacher at Sea
Megan Woodward 
Onboard NOAA Ship Oscar Dyson
July 1 – 18, 2009

Mission: Bering Sea Acoustic Trawl Survey
Geographical Area: Bering Sea/Dutch Harbor
Date: Tuesday, July 5, 2009

Weather/Location 
Position: N 58.37.239; W 171.05.968
Air Temp:  4.5-6.0 (deg C)
Water Temp:  4.94 (deg C)
Wind Speed: 16 knots
Weather: Overcast and rainy

This is the screen I use to get info about our ship’s location. The little white speck inside the red oval is our ship.
This is the screen I use to get info about our ship’s location. The little white speck inside the red oval is our ship.

Science and Technology Log 

We have been at sea now for almost five days in search of pollock. The fish had not been spotted on the lines we traveled on until today. We had the opportunity for our first pollock trawl around 02:00, and used the Methot net to bring in two zooplankton samples earlier in my shift. This was by far the most action yet.  I was eager and ready to see what the fishing process was all about. This log will focus on the zooplankton samples.

The Methot net was put in the water and lowered to the desired depth determined by watching the location of the acoustic return. After twenty minutes the net was brought back up and the catch was unloaded.  I was expecting a net full of euphausiids, but the critters were actually collected in a small container on the back end of the net.  The catch was brought into the fish lab and dumped into a bucket so we could separate the other organisms caught in the net (9 jellyfish and 23 tiny pollock in this case). Once the other fish had been removed, we took a sample (a ••• cup scoop) to weigh and count the euphausiids in the sample (sample is shown above). The rest of the catch was also weighed. 

There were 543 euphausiids in the scoop. The weight and number help estimate the amount of euphausiids in the entire catch. We repeated this process again a few hours later. The second sample had almost twice as many euphausiids, 13 jellyfish and fewer than 5 pollock.

The survey tech and skilled fishermen lower the Methot net into the water.
The survey tech and skilled fishermen lower the Methot net into the water.

Personal Log 

Until today, the fishing portion of this trip remained a mystery.  However, I was feeling a little sea sick, okay very sea sick, so it was probably a good thing. We encountered some VERY rough seas with sustained winds ranging from 30-40 knots and swells averaging 17 ft. Some of the swells were much larger; one was rumored to be almost 35 ft. high.  Apparently the rough seas are expected to return tonight and tomorrow. My sea legs are securely fastened, so I am ready to take on whatever the sea has to offer.

When we brought in the first haul of pollock last night, my eyes must have looked like they were going to roll out of my head.  I couldn’t believe how many fish were coming across the conveyor belt. This was what I had been waiting for, so I got on my rain gear and started sorting the fish.  Each species was placed into separate crates so a count of all fish caught could be taken.  Of course, pollock made up the majority of the catch.  In the next few weeks, I will become an expert member of the pollock survey team. Everyone on board, both scientists and crew, have been more than willing to answer my

A sample of zooplankton brought up in the Methot net. These are euphausiids, which are also referred to as krill.
A sample of zooplankton brought up in the Methot net. These are euphausiids, which are also referred to as krill.

Getting used to the 16:00-04:00 (4pm4am) shift has been trying.  Today’s shift was the first that didn’t require a nap.  Due to the odd shift hours, I’ve been waking up at 14:00 (2 pm) and going to bed around 05:00 (5 am).  This makes mealtime tricky.  Dinner is served first, then I eat some breakfast in the middle of the night. My body is thoroughly confused. The ship’s cooks are wonderful, and continually provide a stocked mess hall with loads of choices.  I swear the dessert bar is continually whispering my name. I couldn’t ask for a more kind, welcoming group of people to work questions. One part of this adventure I’m looking forward to is getting to know the wide range of characters who make this important research possible.

It was certainly a thrill to see the first whale of the trip. The pod was spotted just off the bow of the ship andlater seen in the distance.
It was certainly a thrill to see the first whale of the trip. The pod was spotted just off the bow of the ship andlater seen in the distance.

Animals Seen 

  • Fin Whale
  • Jelly Fish
  • Flathead Sole
  • Northern Flathead Sole
  • Arrow tooth Flounder
  • Pollock
  • Yellow Irish Lord
  • Euphausiids

New Vocabulary 

Zooplankton– A very small or microscopic animal organisms possessing little or no power of locomotion (can’t move themselves), leaving them to merely drift or float in the water.

Euphausiids (eu·phau·si·id) – A type of zooplankton, also known as krill, are tiny shrimp-like crustaceans that form an important part in the diet of many animals including whales, seals, fishes and birds. These are the main food source for pollock.

Methot Net  – Methot is the name of the man who designed the style of plankton net we used to catch the euphausiids.

One of several jellyfish brought up in the nets. This guy is slimy and heavy, but not a stinger
One of several jellyfish brought up in the nets. This guy is slimy and heavy, but not a stinger 

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Megan Woodward, July 1, 2009

NOAA Teacher at Sea
Megan Woodward 
Onboard NOAA Ship Oscar Dyson
July 1 – 18, 2009

Mission: Bering Sea Acoustic Trawl Survey
Geographical Area: Bering Sea/Dutch Harbor
Date: Tuesday, July 1, 2009

Science and Technology Log 

What is this trip all about?  Well, NOAA is working to collect a range of pollock fish samples from across the Bering Sea.  The samples collected will help set fishing regulations based on the estimated pollock fish population.  The fish are looked at to assess the male to female ratio, size and age.

Pollock, a member of the cod family, are mainly found in the Bering Sea. They are typically found between 328 to 984 feet depths. Pollock lives up to 17 years, and reach maturity around age 4. The maximum size of the pollock is slightly larger then 3 feet long.

The colors in the picture at right indicate the amount of return received from the 3 spheres seen towards the top. The other mass of colors at the bottom and surrounding the lines are fish, which are interfering with the read.
The colors in the picture at right indicate the amount of return from the 3 spheres seen towards the top. The other mass of colors at the bottom and surrounding the lines are fish, which are interfering with the read.

We are currently preparing to set sail.  Departure time is set for 15:00 (3:00 pm).  Our first anchoring will take place just a few hundred feet from where we are docked in Dutch Harbor.  At that time, the Chief Scientist and other members of the science team will calibrate (check the accuracy) the echo sound system used during the course of the survey.  Once the calibration is complete and the data is collected, we will continue to sail in search of pollock fish.

The echo sound system is used to measure the amount of return or “back scatter” from a ping (term to describe the sound sent down into the ocean).  Depending on the size of the return, the scientists are able to determine if they are detecting fish.  Pollock are known to give a return within a specific range, which provides the scientists with one of the clues that help them make an educated guess about the type of fish being detected.

In order to calibrate the echo sound system, three metal spheres that have an expected return level are lowered into the sea.  A ping is sent into the open sea, and the scientists are able to watch the amount of return from the spheres through their computer.  The amount of return can be seen using a color-coded scale. Red shows the highest level of return, and gray is the color indicating very little return. The scientists can then see if each sphere is giving the expected return. If a sphere is giving off more or less than the expected return, the scientists then know how to adjust the level of return they are getting from fish throughout the project.

Eagle or seagull? This guy sits and waits for a food meal on top of the hotel dumpster.
Eagle or seagull? This guy sits and waits for a food meal on top of the hotel dumpster.

Personal Log 

After a day and a half in Dutch Harbor, I’m glad to finally be getting under way.  Dutch Harbor is a small, small town.  There are a few restaurants, one hotel and a Safeway.  All of the other businesses are linked to the fishing industry in one-way or another. Flying into the island was an incredible experience. The plane hummed through the air between multiple tiny landforms.  The airport runway stretches out to the edge of the sea, allowing the passengers to think, for just one moment, they are making a water landing. The plane touched down just beyond the shore.

Since my arrival, I have been welcomed with warmth from all of the NOAA scientists and deck crew. Everyone has been more than wiling to answer even the most ridiculous of questions I’ve had. My time the past two evenings were spent getting to know several of the Oscar Dyson officers and crew members.  

A good chunk of Monday was spent hiking Ballyhoo with two of the officers from the ship.  Ballyhoo is a steep hill behind the airport (approx 1400 ft. elevation). The hill was littered with WWII shelters.  As we tromped up the hill, the wind began to pick up. By the time we were nearing the top, the wind was practically knocking me sideways.  The gusts were sustained and powerful. Certainly some of the windiest conditions I’ve encountered. The wildflowers growing on the hillside were reminiscent of the summer blooms found on Mount Rainier. The views from the top were breathtaking.  Several bald eagles swooped past the emerald hills, and the sun started to peak out as we made our way back to sea level.

Animals Seen in Dutch Harbor 

  • Ground Squirrel
  • Jelly Fish
  • Bald Eagles
  • Variety of Seabirds
  • Arctic Fox
  • Guard dog

This little ground squirrel wasn’t bothered as we walked by.
This little ground squirrel wasn’t bothered as we walked by.

New Vocabulary 

Echo Sound System – A tool used to measure the return or “back scatter” from a ping.  The amount of return helps determine what is hiding under the sea.

Ping – The name of the sound that is sent into the water to create an echo/return for the scientists to read. The ping is a constant, repeated sound wave.  Several different frequencies are used to detect objects.

Return  – AKA back scatter, is the amount of acoustic sound waves/echo bouncing back off an object beneath the water.

Trawl – The phrase used when talking about catching fish using a large net

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Jacob Tanenbaum, October 11, 2008

NOAA Teacher at Sea
Jacob Tanenbaum
Onboard NOAA Ship Henry Bigelow
October 5 – 16, 2009

Mission: Survey
Geographic Region: Northeast U.S.
Date: October 11, 2008

Science Log

Greetings from Canada, my son Nicky’s favorite place! We are now in Canadian waters. We have crossed the international boarder. More amazing things keep coming up in our nets. Today we had some interesting sea-stars. Take a look. The larger ones are called Sun-Stars. Do they look like the sun to you? Sea stars are scavengers. They will move around the bottom looking for whatever food is laying around. The legs of the sea star have small tentacles that push food towards the mouth in the center.

Can you find the mouth?
Can you find the mouth?

Did you know that squid can change color? Often male squid change color to attract a mate or to scare off other males who are competing with them. If there are two males near one female, they able to turn one color on the side facing the female, and then turn another color on the other side facing the male.

Squid
Squid

We had more dolphins circling the ship last night. We think our lights may be attracting certain fish or squid, then the dolphins come to eat that. They are not with us during the day at all. One of the benefits, I guess, of being on the night watch. I cannot shoot still photos due to the low light, but have wonderful video. The sounds that you hear on the video were recorded with the ship’s hydrophone. This is a special microphone that can record sounds underwater. The sounds were recorded as the dolphins swam around the ship. You can hear the sound of them swimming by as well as the sound of their sonar as they locate fish to eat. Click here to watch and listen. Thanks to survey technician Pete Gamache for recording this for us. Click here to see the video. Don’t miss it!

Floating Sargassum mat
Floating Sargassum mat

Close up Sargassum
Close up Sargassum

We drove past some seaweed called sargasum weed. It normally grows in an area towards the middle of the Atlantic called the Sargasso Sea. We are well west of the Sargasso, but this seems to have drifted our way. Sargasum Weed grows on the surface of the water. These huge mats of seaweed support an entire ecosystem of sea creatures. Many come to seek shelter in the weeds. Many more come to feed on smaller creatures hiding there.

Snuggy and Zee paid a visit to the fantail of the ship.
Snuggy and Zee paid a visit to the fantail of the ship.

The fantail is an area by the stern of the vessel where the nets are deployed. The photos show the area where the work gets done. Our ship works all night long, of course, and trawls are done at night as well as during the day. Take a look at this video which explains how trawls are done.

NOAA Ship Albatross
NOAA Ship Albatross

Our ship is shadowing another NOAA ship, the Albatross. Why? The Albatross is an old ship and will be replaced by the Bigelow in the years to come. At this point, the ships are trawling in exactly the same place to see if they get similar results in their surveys. Making sure the vessels measure the same thing the same way is called calibration. Right now we are doing calibration with the Albatross.

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IMG_6425-724011Now some answers to your questions:

RM – No we did not see Nantucket yet. We were too far out to sea. We may see it on the way back. Thanks for writing.

T – I love Block Island too. Thanks for the warning about rough seas. I am glad you and your mom are both enjoying the blog as much as I enjoy writing it for you. I’m used to the 12 AM shift now. I that I finally got 8 hours of sleep.

AR – There were TONS of skates in the water.

Hello to Mrs Eubank’s Class. Its great to hear from you. Great questions. Now for answers:

— Amanda, I think fish can get smaller pieces of plastic confused with tiny plankton, but our buoy is too large for that. I don’t think it will hurt fish. I think they will stay away from it.

–Tiffany, this is a tough question and a very good question. I guess over time, our buoy will stop working and will become floating trash. The truth is all science effects the environment you study. The trick is to do more good with your work than harm. Our buoy will help us understand our environment better so that all of us will do less harm in the future. Our ship also burns fuel as we study the ocean. That pollutes a little, but hopefully through our work, we do more good than harm to what we study.

Weston, It felt like the drifter weighs about 35 pounds or so.

Bryce, we use a large net to scoop along the bottom. The opening is about 4 meters wide.

Luke, we have not, nor do I expect to find new species. Our purpose is to learn more about the species that we already know about.

Bryce, we were about 140 miles from the nearest land the last time I looked.

RJ, some scientists made our drifter.

Weston, there are about 1000 drifters right now in the open sea.

I enjoyed your questions. Thanks for writing.

Mr. Moretti’s class, I’m not sure what killed the whale, but remember, all things the live also die. We cannot assume that something human beings did killed that whale. With all the pollution we create, we cannot assume, however, that we did not hurt it. We should stop polluting just to be sure we do not hurt other living things.

Many of you have are working hard to figure out our math question from the other day. Here is how it works. If we are going 8 knots for 24 hours, we multiply 8 times 24 and get 192 knots in a day. If we want to convert that to miles, we multiply again by 1.15 because each knot is 1.15 miles. We get 220.8 Congratulations to all who got this correct. It was a tough question.

Several of you have asked how long I would be on the ship. I will be here until the end of next week. I leave the ship on Friday October 17th.

LP – I enjoy the show Deadliest Catch very much. I think it is cool that scientists sometimes do that same kind of exciting work.

SD, there is no way for me to videotape under that water, but tomorrow I will show you how our sonars (we call them echosounders) work. That is one way to see under the water.

DT from SOMS dont’ worry, there is no light pollution out here. I am on the back deck of a working ship, so right where I am there are lights. I need them to do my job. I just have to go to the upper decks to get away from it or ask the bridge to shut them down for a bit.

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Jessica Schwarz, June 26, 2006

NOAA Teacher at Sea
Jessica Schwarz
Onboard NOAA Ship Rainier
June 19 – July 1, 2006

Mission: Hydrographic Survey
Geographical Area: Alaska
Date: June 26, 2006

Rock hunters: SS Corey Muzzey and ENS Sam Greenaway after a productive morning of investigations. Corey, Sam and Jamie have been very giving of their time and are excellent at explaining data acquisition and processing!
Rock hunters: SS Corey Muzzey and ENS Sam Greenaway after a productive morning of investigations. Corey, Sam and Jamie have been very giving of their time and are excellent at explaining data acquisition and processing!

Science and Technology Log 

So I hope everyone remembers what RAINIER’s Captain, Guy Noll, told me last week before I went out on a launch: “We hit rocks so that you don’t have to.”  When I first heard him say this, I kind of laughed, figuring it was somewhat of an exaggeration, he was only kidding with me. I found out this morning he actually wasn’t.

An added component to running lines and collecting sonar data is doing nearshore feature investigation. If you are involved in feature investigation, your job is to either prove or disprove whether or not a feature (rock, ledge, islet, wreck, etc.) actually exists in the position it’s been historically claimed to be.  When I say “historically” I mean some of these features were last charted based on data collected in the 1940s or earlier.  Therefore, NOAA needs to update the data used in developing their charts and resurvey various areas with updated technology.

For the last several years, NOAA has been augmenting its ship-based sonar surveys with airborne bathymetric LIDAR (LIght Detection and Ranging) data. LIDAR uses high powered laser pulses (invented in 1962!) transmitted from aircraft.  The laser sweeps back and forth across the earth’s surface, and the reflections are detected by a receiver. Much like sonar, the distance to the ground can be inferred from the amount of time required for the light to travel from the airplane, to the earth, and back.  If the position and altitude of the airplane are measured very accurately, the height and shape of features on the earth’s surface can be determined.

ENS Jamie Wasser, monitoring the Echosounder onboard RA1 during investigative surveys.
ENS Jamie Wasser, monitoring the Echosounder onboard RA1 during investigative surveys.

NASA and the U.S. Navy were among the first to use airborne LIDAR.  Later, with the involvement of NOAA, Airborne Oceanographic LIDAR was developed for use in the marine environment.  After continued progress in development and technology, Airborne Hydrographic LIDAR (AHL) was invented. AHL uses a wavelength of light which penetrates the water rather than reflecting off the surface, allowing for measurement of water depths in addition to land topography.  Keep in mind that although ALH was first developed in the mid 80s it was not practical for utilization on the Alaska Peninsula until the 90s. Although an exciting new addition to NOAA’s hydrographic survey “toolbox”, LIDAR is not able to run nearly as deep as sonar. In shallow water close to shore, however, it can reduce the need for inefficient and potentially unsafe small boat operations.  Both LIDAR and sonar are used to assist in determining what features are navigationally significant to those at sea and essentially what features will end up being charted.

RAINIER receives a list of questionable sea features based on information collected from LIDAR, past hydrographic data, and in some cases reports made by mariners.  Based on this collection of data, they are asked by the Pacific Hydrography Branch (the folks in Seattle who compile RAINIER’s data for addition to the charts) to investigate certain features (i.e. rock, ledge, islet etc.) that cannot be resolved with certainty based on the LIDAR or other.

After finishing investigations, TAS Jessica Schwarz is getting a feel for steering a jet-propelled boat!
After finishing investigations, TAS Jessica Schwarz is getting a feel for steering a jet-propelled boat!

So, today, ENS Sam Greenaway, ENS Jamie Wasser, Seamen Surveyor (SS) Corey Muzzey, and I went out looking for rocks☺. That doesn’t sound nearly scientific enough does it? There’s a lot involved in looking for rocks actually, and it’s not nearly as easy as it might sound. For me, as someone new to hydrographic surveying, my big question was, “Okay, and then what happens when we find one?” What’s this whole, “hitting rocks so you don’t have to” idea? Do we really hit the rocks? I rode today in launch RA1 to do investigations.  RA1 is unique because it is a jet propelled boat. This means it does not use a rudder and propeller, like you would expect to find on most power boats. Instead, RA1 is propelled (and steered) using water that is sucked in through a grill in the hull of the boat, accelerated by an impeller driven by a diesel engine, and expelled out a nozzle in the boat’s transom. Changing the direction of the discharge nozzle is what steers the boat. This allows RA1 to go into much shallower water. In fact it only needs 1 foot of water to stay afloat and move around.  Also, don’t be fooled by me saying “jet propelled”.  That might give someone the impression these boats are extremely fast.  RA1 is actually quite slow, with a cruising speed of 12 kts, which I figure was good for the crew while I was at the helm.

There are different ways of investigating features and doing a disproval (determining if a feature is there or not).  One is to use RA1’s single-beam sonar.  This is different from multi-beam sonar (like what I’ve discussed before) because instead of sending out between 140-250 pings of sound over an area of between 120°-150° from the boat, single-beam sonar sends only one ping directly beneath the hull to the ocean floor.  While single-beam sonar is running, the echosounder printer draws an outline of the sea floor features. Check out the picture of ENS Jamie Wasser with the echosounder to get an idea of what it might look like.

If you’re wondering why they aren’t using multi-beam instead, it’s because they’re in shallow water, extremely close to rocks, and it would be much too easy to knock off the multi-beam transducer attached to the hull.  Multi-beam sonars cost around $300,000 so it wouldn’t be very cost effective for NOAA to lose or damage one.  The single-beam sonar is imbedded in the hull and won’t be knocked off if the boat does happen to hit a rock.

Not all survey boats were running item investigations today. In fact today three survey boats were launched, two launches were running main scheme lines with multi-beam sonar (what I’ve participated in on past days) and one, the launch I was involved with today, was running investigations.

In order to do this, the launches need to get extremely close to shore and extremely close to these “hypothesized” features, often times physically nosing the boat up to them to check the positions (remember, “we hit rocks so you don’t have to”).  Depending on the sea conditions, this can be a very difficult process.

Personal Log 

Today was an excellent day. It was beautiful and sunny all day. We stopped the launch and had lunch in one of the little bays. On our way home, SS Corey Muzzey let me drive.  The jet drive boats drive much differently than the boats with rudders and propellers. The helm didn’t feel nearly as touchy and seemed more forgiving of my exaggerated turns of the wheel ☺. We saw several humpbacks out there today…around the time whales started showing up near the boat was when I lost interest in driving.

The landscape here is so incredible.  I keep trying to take digital pictures of it and am always disappointed by what little justice the pictures serve. Tonight is a crew beach party. Everyone on the ship who wants to go can get a ride to a nearby beach to spend some time on land for a change. I’m looking forward to it!

Soon we’ll be crossing the Gulf. I’ve been hearing some horror stories about this crossing, not just from the crew, but also from some of the people I met while I was in Sitka before I came onboard RAINIER.  I’m actually looking forward to being on the open ocean. We’ve spent a lot of time anchored and well protected in the bay.  Crossing the Gulf will be a new experience.  I’m excited!

Calling All Middle Schoolers-We Need Help Answering a Few Questions! 

Sonar technology wasn’t utilized for hydrographic purposes until the 1940s.  Before this, how did surveyors chart the sea floor? Remember, hydrographic surveying and the development of nautical charts, dates all the way back to 1807 with Thomas Jefferson.  So, how did they do it back then?  Let me know what think!