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!

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.

Justin Garritt: Paired Trawling, X-raying, and The Galley Master: September 11, 2018

NOAA Teacher at Sea

Justin Garritt

NOAA Ship Bell M. Shimada

September 1-14, 2018

Mission: Hake Research

Geographical area of cruise: Seattle, Washington to Newport, Oregon

Date: September 9-11, 2018: Day 7-9

Location: West of the Columbia River and Astoria, Oregon

 

Where Are We? After fishing off of the Straits of Juan de Fuca on Friday and Saturday, we headed south.  We ended up west of the Columbia River off the coast of Astoria, Oregon and continued to fish for a few days.

 

The fishing and sampling continues: A typical day consists of the scientists waking up before sunrise to begin scouting for fish. We use the information from the acoustic transducer to find fish.

Chief Scientist Rebecca Thomas

Chief Scientist Rebecca Thomas spots signs of fish on the sonar

sonar from the acoustic transducer

The sonar from the acoustic transducer showing signs of fish

Paired Trawling: Last week I wrote about our goals of the cruise. One of them was to perform paired trawls to determine net size impact to evaluate the differences between the US 32mm net liners and the Canadian 7mm net liners. A paired trawl is when we fish approximately the same location and depth two times using two different size liners. Data is collected on the size, characteristics, and species of fish being caught to eliminate the possibility that there is bias in the data between the two liners. Below are pictures of the nets being sent in and brought back based on information from the sonars. This typically happened 2-4 times per day (1-2 paired trawls).

 

Sorting the Fish Aboard:

rockfish photo shoot

A rockfish photo shoot 🙂

How We Collect Data:

When fish come aboard we follow this flow chart to determine what analysis needs to be done on the catch.

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Our instructional chart for how we analyze the hake and other species

Hake is the majority of the fish we catch. It is also the main species we are researching this cruise.

A random sample of 250 are set aside and the rest are sent back in to the ocean. Of the approximately 250 random hake, 30 are dissected for enhanced sampling (length, weight, sex, maturity, and other projects).

220 are set aside for sex/length analysis. All other species of fish must be logged into the computer and some are kept for special research projects. See pictures below:

Male vs. female hake distinction:

Determining the length of the hake:

Enhanced sampling (length, weight, sex, maturity, and other projects):

IMG_1251

Dissecting the hake to enhance sample

Special Projects: There are also a number of special projects going on aboard:

Fish X-ray: Scientist Dezhang Chu x-rays samples of fish occasionally. The x-ray is used to determine the volume of the swim bladders in certain species of fish (see picture below). The volume of different species’ swim bladders affects the observed acoustics. I spoke to him about the purpose of this study. He said that the present acoustic transducers are great to capture whether fish are present below the ship’s surface but are still not able to classify the type of species being observed. He is working on a team that is trying to use x-ray’s from multiple species to solve that problem. When asked how long he thought it may take for there to be an acoustic system advanced enough to better predict the species onscreen, he said, “People have and will continue to spend their entire careers on improving the system.” If we have more scientists like Dr. Chu on this project, I predict it will be much sooner than he leads on.

"Super Chu"

“Super Chu” and I with his new apron I made him for x-raying

Filming the Catch: Melanie Johnson leads the science team’s visual analysis. During each trawl a camera is placed securely on the net. The purpose of the net is to analyze approximately which depth and time certain fish enter the net.

fish entering the net

Camera footage of fish entering the net

———————————————————————

Getting to know the crew: As promised in other blog posts, here is another interview from the incredible crew aboard  NOAA Ship Bell M. Shimada who continue to make my journey such a rich experience:

Mr. Arnold Dones, Head Chef

Arnold Dones is our head chef or what I like to call him, “Master Chef.” Since the minute I’ve been aboard I quickly noticed the incredible work ethic and talent of our chef. To be clear, every meal has incredible! When I spoke to my mom a few days into the cruise my exact words were, “The food aboard is better than a buffet on a cruise ship. I expected to come aboard for two weeks and lose a few pounds. Well that’s not going to happen!”

Chef Arnold

Chef Arnold and his incredible food artwork

Arnold was born in the Philippines and his family migrated here when he was twenty. When he first got here he knew very little English and worked hard to learn the language and the American culture. He worked a few odd and end jobs until he joined the United States military as a chef. During his first years in the military, he showed so much promise as a chef that he enrolled in “A School” which allowed him to learn how to be a master chef in the military. He spent more than a decade working on military vessels. His last ship placement was aboard the USS Ronald Reagan where he and his team prepared meals for 6,000 soldiers per meal. Two months ago he joined the NOAA Ship Bell M. Shimada family as head chef.  Arnold has two children and a wife who live back in San Diego.

After a tour of the galley with Arnold, I learned how much work it takes to pull 42 meals in 14 days for over 40 crew members without a supermarket nearby. A few weeks out, Arnold has to create his menu for the next cruise leg (typically two weeks). He then has to order the food required to make the meals and do so by staying under a strict budget. When the ship ends a leg and pulls in to port, a large truck pulls up and unloads all his ordered food in large boxes. He then organizes it in the order he plans to prepare it in his large freezer, refrigerator, and store rooms. The trick is to be sure his menu is organized so nothing spoils before it is used.  Arnold’s day begins at 05:00  (5am) and goes until 19:00 (7pm) with a short break after lunch. The only days off he has is a day or two once every two weeks when the boat is in port.

Here is a sample menu for the day:

Breakfast (7-8am)- Eggs benedict, blueberry pancakes, french toast, hash browns, scrambled eggs, oat meal, cut fresh fruit, and breakfast danish.

Lunch (11-12pm)- Bacon wrapped rockfish, chicken wings, Chinese noodles, brussel sprouts, bread, a large salad bar, homemade salads, avocado, bean salad, homemade cookies, and ice cream.

Dinner (5-6pm)-  Stuffed pork chops with spinach and cheese, fine braised chicken thigh, baked salmon, Spanish rice, oven potatoes, peas, dinner rolls, a large salad bar, homemade salads, homemade apple pie, and ice cream.

Snack (24/7)- Soup, crackers, ice cream, and salad/fruit bar

We dock in Newport, Oregon on Friday, September 14, 2018. My final post will be on Friday. Thank you for continuing to follow along in this journey. I am grateful for your support and for the amazing people I have met aboard.

Justin

 

Andrea Schmuttermair, Pollock Processing Gone Wild, July 12, 2015

NOAA Teacher at Sea
Andrea Schmuttermair
Aboard NOAA Ship Oscar Dyson
July 6 – 25, 2015

Mission: Walleye Pollock Survey
Geographical area of cruise: Gulf of Alaska
Date: July 12, 2015

Weather Data from the Bridge:
Latitude: 55 25.5N
Longitude: 155 44.2W
Sea wave height: 2ft
Wind Speed: 17 knots
Wind Direction: 244 degrees
Visibility: 10nm
Air Temperature: 11.4 C
Barometric Pressure: 1002.4 mbar
Sky:  Overcast

Science and Technology Log

I’m sure you’re all wondering what the day-to-day life of a scientist is on this ship. As I said before, there are several projects going on, with the focus being on assessing the walleye pollock population. In my last post I talked about the transducers we have on the ship that help us detect fish and other ocean life beneath the surface of the ocean. So what happens with all these fish we are detecting?

The echogram that shows data from the transducers.

The echogram that shows data from the transducers.

The transducers are running constantly as the ship runs, and the information is received through the software on the computers we see in the acoustics lab. The officers running the ship, who are positioned on the bridge, also have access to this information. The scientists and officers are in constant  communication, as the officers are responsible for driving the ship to specific locations along a pre-determined track. The echograms (type of graph) that are displayed on the computers show scientists where the bottom of the ocean floor is, and also show them where there are various concentrations of fish.

This is a picture of pollock entering the net taken  from the CamTrawl.

This is a picture of pollock entering the net taken from the CamTrawl.

When there is a significant concentration of pollock, or when the data show something unique, scientists might decide to “go fishing”. Here they collect a sample in order to see if what they are seeing on the echogram matches what comes up in the catch. Typically we use the Aleutian wing trawl (AWT) to conduct a mid-water trawl. The AWT is 140 m long and can descend anywhere from 30-1,000 meters into the ocean. A net sounder is mounted at the top of the net opening. It transmits acoustic images of fish inside and outside of the net in real time and is displayed on a bridge computer to aide the fishing operation. At the entrance to the codend (at the end of the net) a CamTrawl takes images of what is entering the net.

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Once the AWT is deployed to the pre-determined depth, the scientists carefully monitor acoustic images to catch an appropriate sample. Deploying the net is quite a process, and requires careful communication between the bridge officers and the deck crew. It takes about an hour for the net to go from its home on deck to its desired depth, and sometimes longer if it is heading into deeper waters. They aim to collect roughly 500 fish in order to take a subsample of about 300 fish. Sometimes the trawl net will be down for less than 5 minutes, and other times it will be down longer. Scientists are very meticulous about monitoring the amount of fish that goes into the net because they do not want to take a larger sample than needed. Once they have determined they have the appropriate amount, the net is hauled back onto the back deck and lowered to a table that leads into the wet lab for processing.

Here the scientists, LT Rhodes, and ENS Kaiser assess the catch.

Here the scientists, LT Rhodes, and ENS Kaiser assess the catch.

We begin by sorting through the catch and pulling out anything that is not pollock. We don’t typically have too much variety in our catches, as pollock is the main fish that we are after. We have, however, pulled in a few squid, isopods, cod, and several jellies. All of the pollock in the catch gets weighed, and then a sub-sample of the catch is processed further. A subsample of 30 pollock is taken to measure, weigh, collect otoliths from, and occasionally we will also take ovaries from the females. There are some scientists back in the lab in Seattle that are working on special projects related to pollock, and we also help these scientists in the lab collect their data.

The rest of the sub-sample (roughly 300 pollock) is sexed and divided into a male (blokes) and female (sheilas) section of the table. From there, the males and females are measured for their length. The icthystick, the tool we use to measure the length of each fish, is pretty neat because it uses a magnet to send the length of the fish directly to the computer system we use to collect the data, CLAMS. CLAMS stands for Catch Logger for Acoustic Midwater Survey. In the CLAMS system, a histogram is made, and we post the graphs in the acoustics lab for review. The majority of our pollock so far have been year 3. Scientists know this based on the length of pollock in our catch. Once all of the fish have been processed, we have to make sure to clean up the lab too. This is a time I am definitely thankful we have foul weather gear, which consists of rubber boots, pants, jackets and gloves. Fish scales and guts can get everywhere!

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Personal Log

Here is one of many jellies that we caught. .

Here is one of many jellies that we caught. .

I am finally adjusting to my nighttime shift schedule, which took a few days to get used to. Luckily, we do have a few hours of darkness (from about midnight until 6am), which makes it easier to fall asleep. My shift runs from 4pm-4am, and I usually head to bed not long after my shift is over, and get up around noontime to begin my day. It’s a little strange to be waking up so late in the day, and while it is clearly afternoon time when I emerge from my room, I still greet everyone with a good morning. The eating schedule has taken some getting used to- I find that I still want to have breakfast when I get up. Dinner is served at 5pm, but since I eat breakfast around 1 or 2pm, I typically make myself a plate and set it aside for later in the evening when I’m hungry again. I’ll admit it’s a little strange to be eating dinner at midnight. There is no shortage of food on board, and our stewards make sure there are plenty of snacks available around the clock. Salad and fruit are always options, as well as some less healthy but equally tasty snacks. It’s hard to resist some of the goodies we have!

Luckily, we are equipped with some exercise equipment on board to battle those snacks, which is helpful as you can only walk so far around the ship. I’m a fan of the rowing machine, and you feel like you’re on the water when the boat is rocking heavily. We have some free weights, an exercise bike and even a punching bag. I typically work out during some of my free time, which keeps me from going too crazy when we’re sitting for long periods of time in the lab.

Up on the bridge making the turn for our next transect.

Up on the bridge making the turn for our next transect.

During the rest of my free time, you might find me hanging out in the lounge watching a movie (occasionally), but most of the time you’ll find me up on the bridge watching for whales or other sea life. The bridge is probably one of my favorite places on the ship, as it is equipped with windows all around, and binoculars for checking out the wildlife. When the weather is nice, it is a great place to sit outside and soak in a little vitamin D. I love the fact that even the crew members that have been on this ship for several years love seeing the wildlife, and never tire of looking out for whales. So far, we’ve seen orcas, humpbacks, fin whales, and Dall’s porpoises.

 

 

 

Did you know? Otoliths, which are made of calcium carbonate, are unique to each species of fish.

Where on the ship is Wilson?

Wilson the ring tail camo shark is at it again! He has been exploring the ship even more and made his way here. Can you guess where he is now?

Where's Wilson?

Where’s Wilson?

Where's Wilson?

Where’s Wilson?

Andrea Schmuttermair, Anchors Away from Kodiak, July 7, 2015

NOAA Teacher at Sea
Andrea Schmuttermair
Aboard NOAA Ship Oscar Dyson
July 5 – 25, 2015

Mission: Walleye Pollock Survey
Geographical area of cruise: Gulf of Alaska
Date: July 7, 2015

Weather Data from the Bridge:

Latitude: 56 36.1N
Longitude: 156 04.1W

Visibility: 10nm
Speed: 12 knots
Wind Speed: 4 knots
Wind Direction: 202 degrees
Surface Water Salinity:35.31
Air Temperature: 12.6 C
Barometric Pressure: 1004.6 mbar
Sky: SCT (scattered clouds)

TASAK15 (12)

One of the signs from my walk along the docks in Kodiak. I learned a lot about Kodiak and the fishing industry by reading these signs.

Science and Technology Log:

The walleye pollock fishing industry is the largest commercial fishing industry in the country, and one of the largest fishing industries in the world. Have you eaten fish sticks? Filet-O-Fish from McDonald’s? Imitation crab? If your answer is yes to any of these questions, then you have eaten walleye pollock. Since pollock supports such a large industry, scientists need to carefully monitor its abundance each year. Bring on the scientists and crew on board the Oscar Dyson to make this mission possible.

TIn summer, and in a few locations in winter, scientists head out to assess the walleye pollock population in both the Bering Sea and in the Gulf of Alaska. The summer survey alternates between the two areas, and this summer we are traveling in the Gulf of Alaska for our survey. This second leg (out of 3 legs total) will head counterclockwise around the island of Kodiak. This survey, conducted by the Midwater Assessment and Conservation Engineering Program at the Alaska Fisheries Science Center in Seattle, uses acoustic technology to gather data on the distribution and abundance of fish, which provides researchers with pertinent information about the walleye pollock population.

The Oscar Dyson at Pier 2 before departure from Kodiak.

The Oscar Dyson at Pier 2 before departure from Kodiak.

The Oscar Dyson is a relatively new ship, equipped with noise quieting technology in order to create as little acoustic disturbance as possible when out at sea. Another neat feature crucial to the work of the Dyson is the acoustic transducers located on the bottom of the ship. There are several of these transducers, which are composed of small ceramic disks, and they help scientists detect ocean life and map the seafloor. If you are like me, you are probably wondering what a transducer is, right? It took me a couple of explanations and analogies in order to understand what was happening in these tiny devices. Remember, sound waves are pressure waves that move through a medium, in this case water. The transducer converts electrical energy to mechanical energy, expanding and contracting with electrical signal it receives. This expansion and contraction creates sound waves that move through the water away from the transducers. After sending the pressure waves the transducer switches modes to “listen” to the incoming waves. When the sound waves hit something in the water they are reflected back to the transducer. These reflected waves that are received by the transducers indicate the presence of obstacles in the water. An analogy for this process is that the transducer first acts as a speaker and then as a microphone.

The transducers on the bottom of the ship sending out a signal to the ocean floor.

The transducers on the bottom of the ship sending out a signal to the ocean floor.

Five of these transducers are being used for the pollock survey in order to detect pollock and other ocean life. The information the transducer receives back is automatically graphed on the computer. Scientists and other crew members can view and analyze this graph, and will use this information to determine when it is appropriate to send out a trawl to collect fish. There are also several transducers located around the bottom of the ship that are gathering information about the ocean floor. Hydrographic surveys use this technology as they map the sea floor. I am amazed at where we have come with technology, especially out at sea. Stay tuned for my next post to learn about more amazing technology we are using on board!

Personal Log:

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Ready to fly on this little plane from Anchorage to Kodiak.

Lucky. That is how I would describe myself when I landed at the Kodiak airport on my flight from Anchorage. First, I was lucky that the flight I was scheduled on made it to Kodiak on its first attempt, as flights are often cancelled for poor weather or low visibility. Planes have been known to turn around and fly back to Anchorage if they can’t make a safe landing in Kodiak. I am also feeling very lucky to have the opportunity to partake in yet another assignment as a NOAA Teacher at Sea, in another area of the country I haven’t yet explored.

I arrived in Kodiak on the 4th of July, and was swept up from the airport by one of the NOAA Corps officers, ENS Justin Boeck. We weren’t scheduled to depart on the Oscar Dyson until Monday, July 6th, so Justin gave me a quick tour of the ship. I wasn’t sure what to expect of the Oscar Dyson, but when my first thoughts climbing on board were that it would take me a week to find my way around! It is much larger than the last ship I was on, the Oregon II, down in the Gulf of Mexico.

Trying to take advantage of the nice weather, I decided to explore the area before we left. The town of Kodiak is quaint, and in walking through the downtown area, it is clear that fishing has been and will continue to be integral to the way of life here.

The science crew came in on the 4th as well from Seattle. I met them all when we went out to dinner Saturday evening. Even though we are going to be sleeping on the ship for next 2 nights before we depart, meals won’t be served until we are underway. I did manage to track down some good sushi and seafood places here in town, and am quite satisfied!

This sculpture was made entirely of trash found in the ocean.

This sculpture was made entirely of trash found in the ocean.

On Sunday, the weather turned for the worse, which made the walk into town for coffee a wet one. If you think weather changes quickly in Colorado, try coming to Alaska. My favorite image of the weather status was at a little shop in Homer, Alaska, which outlined a box with a marker on the window and wrote, “If you want to know the weather, look here.”

That afternoon, I was given a little orientation on what some of my tasks would be on the ship, as there is quite a bit going on in addition to the pollock survey. I will be spending most of my time in the acoustics lab analyzing data, the wet lab processing our catches, and chem lab for some of the special projects.

In the evening, the weather cleared just long enough for me to convince ENS Gilman (ok, he didn’t really need any convincing- he was just as excited as I was) to head down to the pier to test out the Waverunner, the ROV made by the students in my class. While the visibility was not the best, we were able to see plenty of moon jellies, sea anemones and some kelp beds. The ROV handled pretty well in the ocean, although we did have some difficulties bringing it back up when it went down too deep. Students, do you have any suggestions for how we could account for this? Any suggestions or modifications we need to make?

We were supposed to be leaving early afternoon on Monday, however due to the bad weather, several of our crew members had not yet made it in to Kodiak. They finally made it over later that afternoon and we left port at 11pm. I stayed up to watch the sun set as we were leaving port (yes, it does actually set in parts of Alaska), and pushed myself to stay awake for a few more hours. I’ll be working the night shift for the next few weeks, which means I’m on duty from 4pm-4am. The faster I can get myself used to this schedule, the better off I’ll be. The first days in Kodiak have been a blast, and I am excited to begin conducting our survey!

Checking out the ship before we set sail.

Checking out the ship before we set sail.

Did you know? Acoustic transducer technology has been in use since World War II.

Where on the ship is Wilson?

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Wilson, our ring tail camo shark (so aptly named by our awesome science crew) , has been enjoying his time on the ship as much as I have. He has traveled all over the place, and is having fun with the crew on board. Can you guess where he is in the picture above?

Kacey Shaffer: Let’s Go Fishing! August 1, 2014

NOAA Teacher at Sea

Kacey Shaffer

Aboard NOAA Ship Oscar Dyson

July 26 – August 13, 2014

Mission: Walleye Pollock Survey

Geographical Location: Bering Sea

Date: August 1, 2014

Weather information from the Bridge:

Air Temperature: 9.7° C

Wind Speed: 11.9 knots

Wind Direction: 153°

Weather Conditions: Foggy

Latitude: 58°19’42 N

Longitude: 175°14’66 W

 

Science and Technology Log:            

If you’ve ever been fishing, be it on a lake, river or stream, you know it is not productive to fish all day in a spot where they aren’t biting. If the fish aren’t biting in one spot, you would most likely pack up and move to a different spot. Now imagine trying to fish in an area that is 885,000 square miles. The equivalent to trying to find a needle in a haystack! Luckily, the Oscar Dyson has sophisticated equipment to help us determine where the fish are hanging out. Allow me to introduce you to a very important location on the ship – The Acoustics Lab.

When you enter The Acoustics Lab, you’ll immediately see a wall of nine computer screens. The data shown on the screens help Chief Scientist Taina and Fishery Biologist Darin make the key decision of where we will deploy the nets and fish. What information is shown on the screens? Some show our location on the transect lines we are following, which is similar to a road map we would use to get from point A to point B on land. The transect lines are predetermined “roads” we are following. Another screen tells us which direction the boat is heading, barometric pressure, air temperature, surface temperature, and wind direction and wind speed. The most technical screens show the data collected from transducers attached to the bottom of the ship on what is referred to as the Center Board. There are five transducers broadcasting varying frequencies. Frequency is the number of sound waves emitted from a transducer each second. The Dyson transducers emit sound waves at 18kHz, 38kHz, 70kHz, 120kHz and 200kHz (kHz= kilohertz). Why would it be necessary to have five transducers? Certain organisms can be detected better with some frequencies compared to others.  For example, tiny organisms like krill can be seen better with higher frequencies like the 120kHz compared to the lower frequencies. Also the lower frequencies penetrate farther into the water than the higher frequencies so they can be used in deeper water. Having this much data enables the scientists to make sound decisions when choosing where to fish.

A map of the Bering Sea showing transect lines in white. During this pollock survey the Oscar Dyson follows transect lines which benefits both the crew and scientists.

A map of the Bering Sea showing transect lines in white. During this pollock survey the Oscar Dyson follows transect lines which benefits both the crew and scientists.

Transducers produce these images displayed on the screens in the Acoustics Lab. The thick red line at the bottom is the sea floor and the  many red, oblong shaped areas indicate large clusters of fish. Let’s go fishing!

Transducers produce these images displayed on the screens in the Acoustics Lab. The thick red line at the bottom is the sea floor and the many red, oblong shaped areas indicate large clusters of fish. Let’s go fishing!

Personal Log:

Each time I share a blog post with you I am going to focus on one area of the ship so you can get acquainted with my new friend, Oscar Dyson. I’ll begin sharing about my stateroom and the lounge. I was very surprised by the size of my room when I arrived last Thursday. My roommate is Alyssa, a Survey Tech. You will learn more about her journey to the Dyson later. She has been on the ship for a while so she was already settled in to the top bunk which put me on the bottom bunk! The beds are very comfortable and the rocking motion of the ship is really relaxing. I’ve had no trouble sleeping, but then again, when have I ever had trouble sleeping?! We have our own private bathroom facilities, which is a definite bonus. Take a look at our room.

The stateroom Kacey shares with Alyssa.

The stateroom Kacey shares with Alyssa.

Our stateroom's private bath. Could that shower curtain be any more fitting?!

Our stateroom’s private bath. Could that shower curtain be any more fitting?!

Alyssa and I are on opposite shifts. She works midnight to noon and I work 4:00pm to 4:00am. There is a little bit of overlap time where she’s off and I haven’t gone to work yet. This is quite common for all of the people on the ship. This is a twenty-four hours a day, seven days a week operation. Someone is always sleeping and someone is always working. Fortunately there is a place where we can hang out without bothering our roommates. The Lounge is a great place to kick back and relax. There are comfy chairs and a very large couch and a television with the ability to play dvd’s or video games. Over the years people have brought books with them and then left them on the ship so we have an enormous library. Sometimes there are people just reading in the Lounge and other times a group of us will watch a movie together. There is one important rule of showing movies…if you start a movie you have to let it play all the way out. Even if you get bored with it or need to leave you must let it play because someone may be watching it in their room. It would be rude of us to continually shut movies off an hour into them!

Career Connections: ST Alyssa Pourmonir

ST Pourmonir checks data on the computer during a CTD deployment.

ST Pourmonir checks data on the computer during a CTD deployment.

Alyssa hails from Pennsylvania. During her senior year of high school she chose to further her education at the Coast Guard Academy. She spent three years studying with the Coast Guard, but ultimately graduated from SUNY Maritime this past January. Alyssa landed a 10 week internship with a NASA facility in Mississippi. During the course of her internship she learned of an opportunity with NOAA. This position would be a Survey Tech, traveling on one of NOAA’s many ships. She arrived at the Dyson only a few weeks before I did.

Alyssa has many responsibilities as a Survey Tech. She assists with the deploying and recovery of the CTD instrument, helps process fish in the wet lab, completes water tests, and serves as a liaison between the ship’s crew and its scientists. When a trawling net is deployed or recovered, Alyssa is on the deck to attach or detach sensors onto the net. She also looks for safety hazards during that time.

When asked what the best part of her job is she quickly responds learning so much science is the best! As a Survey Tech, she gets the chance to see how all the different departments on the ship come together for one mission. She works closely with the scientists and is able to learn about fish and other ocean life. On the other hand, she also works side-by-side with the ship’s crew. This allows her to learn more about the ship’s equipment. Being the positive person she is, Alyssa turned the hardest part of her job into a benefit for her future self. Adjusting to 12 hour shifts has been a challenge but she noted this can also be helpful. When she is super busy she is learning the most and it also makes the time go faster.

Looking ahead to her future, Alyssa sees herself getting a Master’s Degree in a science related field. Some areas of interest are oceanography, remote sensing or even meteorology. Alyssa’s advice for all high school students: STUDY SCIENCE!

Did you know?

Lewis Richardson, an English meteorologist, patented an underwater echo ranging device two months after the Titanic sunk in 1912.

Johanna Mendillo: Hello pollock…. can you hear me now? August 7, 2012

NOAA Teacher at Sea
Johanna Mendillo
Aboard NOAA ship Oscar Dyson
 July 23 – August 10

Mission: Pollock research cruise
Geographical area of the cruise: Bering Sea
Date: Tuesday, August 7, 2012

Location Data from the Bridge:
Latitude: 59 52 ’ N
Longitude: 177 17’ W
Ship speed:   8.0 knots ( 9.2 mph)

Weather Data from the Bridge:
Air temperature: 7.3C (45.1ºF)
Surface water temperature: 8.4C (47.1ºF)
Wind speed:  4 knots ( 4.6 mph)
Wind direction: 75T
Barometric pressure:  1018 millibar (1 atm)

Science and Technology Log:

We are wrapping up our final few sampling transects.  Now that you are practically fisheries biologists yourselves from reading this blog, students, we must return to the fundamental question— how do we FIND the pollock out here in the vast Bering Sea?  The answer, in one word, is through ACOUSTICS!

Look at all of these birds off the stern!  Why do you think they are following us?  Are we about to haul up a catch, perhaps?

Look at all of these birds off the stern! Why do you think they are following us? Are we about to haul up a catch, perhaps?

Hydroacoustics is the study of and application of sound in water.  Scientists on the Oscar Dyson use hydroacoustics to detect, assess, and monitor pollock populations in the Bering Sea.

Now, you may have heard of SONAR before and wonder how it connects to the field of hydroacoustics.  Well, SONAR (SOund Navigation and Ranging) is an acoustic technique in which scientists send out sound waves and measure the “echo characteristics” of targets in the water when the sound waves bounce back— in this case, the targets are, of course, the pollock!  It was originally developed in WWI to help locate enemy submarines!  It has been used for scientific research for over 60 years.

(PLEASE NOTE: The words sonar, fishfinders, and echosounders can all be used interchangeably.)

The transducer sends out a signal and waits for the return echo...

The transducer sends out a signal and waits for the return echo once it bounces off the fish’s swim bladder… (Source: http://www.dosits.org)

On the Dyson, there is, not one, but a collection of five transducers on our echosounder, and they are set at five different frequencies.  It is lowered beneath the ship’s hull on a retractable centerboard.  The transducers are the actual part of the echosounder that act like antennae, both transmitting and receiving return signals.

The transducers transmit (send out) a “pulse” down through the water, at five different speeds ranging from 18-200kHz, which equals 18,000-200,000 sound waves a second!

When the pulse strikes the swim bladders inside the pollock, it gets reflected (bounced back) to the transducer and translated into an image.

First of all, what is a swim bladder?  It is simply an organ in fish that helps them stay buoyant, and, in some cases, is important for their hearing.

Swim Bladder (Source: www.education.com)

Swim Bladder (Source: http://www.education.com)

Now, why do the pulses bounce off the swim bladders, you ask?  Well, they are filled mostly with air and thus act as a great medium for the sound waves to register and bounce back.

Think of it this way: water and air are two very different types of materials, and they have very different densities.  The speed of sound always depends on the material through which the sound waves are traveling through.  Because water and air have very different densities, there is a significant difference in the speed of sound through each material, and that difference in speed is what is easy for the sonar to pick up as a signal!

It is the same idea when sound waves are used to hit the bottom of the ocean to measure its depth- it is easy to read that signal because the change in material, from water to solid ground, produces a large change in the speed of the sound waves!

Here is a sonar system measuring the depth of the ocean...

Here is a sonar system measuring the depth of the ocean… (Source: http://www.dosits.org)

Interestingly, different types of fish have different shaped and sized swim bladders, and scientists have learned that they give off different return echos from sonar signals!  These show up as slightly different shapes on the computer screen, and are called a fish’s “echo signature”.  We know, however, that we will not encounter many fish other than pollock in this area of the Bering Sea, so we do not spend significant time studying the echo signatures on this cruise.

So, what happens when these signals return to the Dyson?  They are then processed and transmitted onto the computer screens in the hydroacoutsics lab on board.  This place is affectionately known as “the cave” because it has no windows, and it is, in fact, the place where I spend the majority of my time when I am not processing fish!  Here it is:

Here is Anatoli observing potential fish for us to go catch!

Here is Anatoli observing potential fish for us to go catch!

We spend a lot of time monitoring those computer screens, and when we see lots of “specks” on the screen, we know we have encountered large numbers of pollock!

Here we are approaching a LARGE group of pollock!

Here we are approaching a LARGE group of pollock!

When the scientists have discussed and confirmed the presence of pollock, they then call up to the Bridge and announce we are “ready to go fishing” at a certain location and a certain depth range!  Then, the scientists will head upstairs to the Bridge to work with the officers and deck crew to supervise the release, trawling, and retrieval of the net.

Now, in addition to the SONAR under the ship, there are sensors attached to the top of the net itself, transmitting back data.  All of the return echos get transmitted to different screens on the bridge, so not only can you watch the fish in the water before they are caught, you can also “see” them on a different screen when they are in the net!  As I told you in the last post, we will trawl for anywhere from 5-60 minutes, depending on how many fish are in the area!

Left: Echosounder at work/  Right: The "return signature" is visible on the computer!

Left: Echosounder at work/ Right: The “return signature” is visible on the computer!  (Source: http://www.dosits.org)

A full catch- success!  Without acoustics, it would be much harder for NOAA to monitor and study fish populations.

A full catch- success! Without acoustics, it would be much harder for NOAA to monitor and study fish populations.

Personal Log:

In these last few days, we have crossed back and forth from the Russian Exclusive Economic Zone (EEZ) and the U.S. several times.  There were some nice views of Eastern Russia before the clouds and fog rolled in!

I can see Russia from my ship!

I can see Russia from my ship! (Photo Credit: Allan Phipps)

In addition, we crossed over the International Date Line!  It turns out that everyone on board gets a special certificate called the “Domain of the Golden Dragon” to mark this event.  This is just one of a set of unofficial certificates that began with the U.S. Navy!  If you spend enough time at sea, you can amass quite a collection- there are also certificates for crossing the Equator, Antarctic Circle, Arctic Circle, transiting the Panama Canal, going around the world, and more…

I will award a prize to the first person who writes back to tell me what does it mean when one goes from a “pollywog” to a “shellback”, in Navy-speak!

Here is a picture of me with the largest pollock I have seen so far- 70cm!

If I am 5' 4", how many 70cm pollock would it take to equal my height?

If I am 5′ 4″, how many 70cm pollock would it take to equal my height?

Lastly, on to some, perhaps, cuter and more cuddly creatures than pollock- pets!  Here in the hydroacoustics lab, there is a wall dedicated to pictures of pets owned by the officers, crew, and scientists:

Those are some pretty cute pets left ashore...

Those are some pretty cute pets left ashore…

Clearly, this is a dog crowd!   I did learn, however, that our Chief Scientist, Taina, has her cat (Luna) up there!  Students, do you remember the name of my cat and, what do you think, should I leave a picture of her up here at sea?

Kaci Heins: Surveying and Processing, September 30 – October 3, 2011

NOAA Teacher at Sea
Kaci Heins
Aboard NOAA Ship Rainier
September 17 — October 7, 2011

Mrs. Heins Taking a CTD Cast


Mission: Hydrographic Survey
Geographical Area: Alaskan Coastline, the Inside Passage
Date: Tuesday, October 4, 2011


Weather Data from the Bridge

Clouds: Overcast 7/8
Visibility: 8 Nautical Miles
Wind: 21 knots
Temperature
Dry Bulb: 12.0 degrees Celsius
Barometer: 997.0 millibars
Latitude: 55.23 degrees North
Longitude: -133.22 degrees West

Science and Technology Log

Watching The Sonar

I was able to go out on another launch boat Sunday to collect survey data.  It was a beautiful day with amazing scenery to make it by far the best office I have ever been too.  Despite the fact that the ship is usually “off the grid” in many ways, the location of their work environment, or office, in Alaska is visually stunning no matter where you turn.  Keeping your eyes off the cedar trees and focused on the sonar in a launch can be challenging at times!  However, when there is a specific job to be done that involves time and money, then the scenery can wait until the job is finished.  During Sunday’s launch survey we had to clean up some “Holidays” and acquire some cross line data.

View Of the Data Acquired For the Ship On The Bridge

The word “Holiday” might lead to some confusion about what you might think we are doing when you read that word.  Holiday =vacation right?  In this case it is when there is a gap, or missing information, in the survey data that is acquired.  This poses a problem for the survey technicians because this leaves holes in the data that they must use for their final charts.  Holidays can be caused by the boat or ship being off the planned line, unexpected shoaling (or where the water gets shallow) so the swath width decreases, or a slope angling away from the transducer so that a return path for the sound wave is not possible.  The speed, direction, weather, swells, rocking of the boat, and the launches making wider turns than anticipated. It is easy to see where holidays occur as we are surveying because amidst the rainbow of color there will be a white pixel or square showing that data is missing.  When we are finished surveying or “painting” an area, we communicate with the coxswain where we need to go back and survey over the missing data or holidays.  If there are holidays or data is missing from the survey, then the survey technicians must explain why the data is missing in their final Descriptive Report.  This document covers everything that was done during the project from how the area was chosen to survey, what data was collected, what data wasn’t collected and why.  This is where holidays are explained, which could be due to lack of time or safety concerns.

Ship Hydrographic Survey

This launch was a little different because we were cleaning up holidays from the Rainiers’ multibeam.  Not only do the smaller survey boats collect sea floor surface data, but the Rainier has its own expensive multibeam sonar as well.  The ships sonar is called a Kongsberg EM 710 and was made in Norway.  Having the Rainier fitted with a multibeam sonar allows the ship to acquire data in deeper water and allows for a wider swath coverage.  The lines that are surveyed on the ocean floor are also much longer than those in a launch.  This means that instead of taking around 5-10 minutes to acquire a line of data, it can take around 30 minutes or more with the ship.  This is great data because again, the ship can cover more area and in deeper water. We also took the ships previous data and ran cross lines over it.  The importance of running a cross line over previous survey data helps to confirm or deny that the data acquired is good data.  However, there is a catch to running a cross line.  To confirm the data they have to use a different system than what was used before, the cross line has to be conducted on a different day, and it has to be during a different tide.  All of this is done to know for sure that the data is acquired has as few errors as possible before the projects are finished.

Rainier Multibeam Sonar

Personal Log

Each day when the scientists go out and survey the ocean floor they acquire tens of gigabytes of information!  The big question is what is next after they have acquired it all?  When they are on the launch they have a small external hard drive that holds 500 gigabytes to a terabyte of information plugged into their computer.  At the end of the day all their information and files are downloaded to this hard drive and placed in a water tight container in case it happens to get dropped.  Keeping the newly acquired data safe and secure is of the utmost importance.  Losing data and having to re-survey areas due to a human error costs tens of thousands of dollars, so everything must get backed up and saved constantly.  This is where I have noticed that computer skills and file management are so important in this area of research.

Once we get off of the boats the data is brought upstairs to what is called the plot room.  This is where all the survey technicians computers are set up for them to work on their projects.  The technicians that are in charge of downloading all the data and compiling all the files together is called night processing.  There are numerous software programs (tides, CTD casts, POS, TPU, Hypack,) and data from these programs that all have to be combined so that the technicians can produce a finished product for the Pacific Hydrographic Branch (part of Hydrographic Surveys Division), who then process the data some more before submitting to Marine Charting Division to make the final chart. The main software program that combines all the different data is called Caris and comes out of Canada.  Once all of the data has been merged together it allows the technicians start cleaning up their data and produce a graphic plan for the launches to follow the next day.  Every movement on the keyboard or with the mouse is very important with surveying because everything is done digitally.  Numerous new files are created each day in a special way so that anyone that reads the name will know which ship it came from, the day, and the year.  File management and computer skills are key to keeping the flow of work consistent and correct each day.

Hydrographic Survey Data In Caris

We have also had numerous fire drills while on the ship.  This is very important so that everyone knows where to go and what to do in case of an emergency.  They had me help out with the fire fighters and the hose this time.  I learned how to brace the fire fighter so that the force from the hose doesn’t knock them over.  I never knew that would be an issue with fire fighting until this drill.  I learn so many new things on this ship every day!

Fire Drill Practice

Student Questions Answered


Kingfisher

Animals Spotted

Kingfisher

Sea Otters

Question of the Day