Helen Haskell: Data Acquisition Through Small Boat Surveying, June 12, 2017

 

NOAA Teacher at Sea

Helen Haskell

Aboard NOAA Ship Fairweather

June 5 – 22, 2017

Mission: Hydrographic Survey

Geographic Area of Cruise: Southeast Alaska – West of Prince of Wales Island

Date: June 12, 2017

Weather Data:

Temperature: 13°C

Wind 12 knots, 230° true

10 miles visibility

Barometer: 1016 hPa

90% cloud cover at 2000 feet

Location:  Dall Island, AK  54° 54.5’N  132°52.1W

 

Science and Technology Log:

The role of the Fairweather is to conduct hydrographic surveys in order to acquire data to be used in navigational charts. While the Fairweather has sonar equipment and collects lots of data in transit, much of the data collected on a daily basis is by using smaller boats, with a rotating crew of 3-4 people per boat. The Fairweather will sail to the research area and drop anchor, and for multiple days crews will use these smaller vessels to collect the raw data in an area.

 

“Sonar” was originally an acronym for Sound Navigation and Ranging, but it has become a word in modern terminology. The boats contain active sonar devices used by the NOAA scientists to calculate water depth, document the rocks, wrecks and kelp forests, and in general, determine hazards to boats. Ultimately their data will be converted in to navigational charts – but there is a significant amount of work and stages to be undertaken to make this a reality.

Attached to the small boats are Kongsberg Multi Beam Echo Sounders (MBES). These devices emit sound waves in to the water. The waves fan out and reflect off the bottom of the sea floor and return to the MBES. Based on the time it takes for the MBES to send and receive the sound waves, the depth of the sea floor can be calculated. As the boat moves through the water, thousands of pieces of data are collected, and collectively a picture of the sea floor can be built.

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The pink line is the sea floor

It sounds simple, right? But I am beginning to understand more about the complexities that go in to a project of this scope. It would seem simple perhaps, to drive a boat around, operate the MBES and collect data. As I have quickly come to understand, there is a lot more to it.

As mentioned before, due to the weather conditions in the geographic area of study and routine maintenance, the Fairweather has a field season, and a dry dock season. During the non-field season time, data is analyzed from the previous seasons, and priorities and plans are made for the upcoming seasons. Areas are analyzed and decisions made as to which regions the Fairweather will go to and sheets are determined. A sheet is a region within the project area. Each sheet is broken up in to polygons. On any given day, one small boat will cover 1-3 polygons, depending on the weather, the complexity of the area, and the distance of travel from the Fairweather.

 

There are many parameters that the scientists need to consider and reconfigure to acquire and maintain accurate data collection. A minimum density of soundings (or ‘pings’) is required to make sure that the data is sufficient. For example, in shallow waters, the data density needs to be a minimum of five soundings per one square meter. At a greater depth, the area covered by the five soundings can be 4 square meters. This is due to the fact that the waves will spread out more the further they travel.

A coxswain will drive the boat in lines, called track lines, through the polygon. As the data is collected the ‘white chart’ they are working with begins to get colored in. Purple indicates deepest water. Green and yellow mean it’s getting less deep. Red indicates shallow areas, and black needs to be avoided. In the pictures below you can begin to see the data being logged visually on the map as the boat travels.

 

Make an analogy to mowing a lawn. There are areas of most lawns where it is easy to push the lawnmower in straight lines, more or less. The same can be said for here, to some extent. In the deeper waters, not close to shore, the boats can ‘color in’ their polygon using relatively wide swaths that allow the sonar data to overlap just slightly. Every time the boat turns to go back in the opposite direction, the MBES is paused, and then started again once the boat is in position, making a new track line. Close to the shore, referred to as near shore, there are usually more hazards. In these areas, speed is slowed. Due to the increased potential of rocks and kelp beds in an unknown area, the boats do something called half-stepping, in-effect overlapping the ‘rows’ – think about re-mowing part of that section of lawn, or mowing around tree trunks and flower beds. As a visual image comes up on the screen, the coxswain and the hydrographers can determine more where their next line will be and whether they should continue surveying that area, or if there are too many hazards.

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Data aquisition

Full coverage needs to be achieved as much as possible. At times this does not happen. This can be as the result of several factors. Kelp increases the complexity of data collection. Kelp often attaches to rocks, and there are large ‘forests’ of kelp in the areas being surveyed. As the sonar also ‘reads’ the kelp, it’s not possible to know the true location, size and depth of the rock the kelp is attached to, and in some instances, to determine if the kelp is free floating.

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Kelp

Steep slopes, rocks and kelp can also create ‘shadows’ for the MBES. This means that there are areas that no sounding reached. If possible the survey team will re-run a section or approach it from another angle to cover this shadow. At times, the rocky areas close to shoreline do not allow for this to be done safely.  A holiday is a term used by the survey crew to describe an area where data did not register or was missed within a polygon or sheet. During data collection, a day may be dedicated for boats to return to these specific areas and see if the data can be collected. On occasion, weather conditions may have prevented the original crew from collecting the data in the first place. Equipment malfunction could have played a role, as could kelp beds or hazardous rock conditions.

Survey crews are given several tools to help them navigate the area. Previous nautical charts are also superimposed on to the electronic chart that the surveyors are using. While many of these contain data that is out of date, it gives the crew a sense of what hazards in the area there may be. Symbols representing rocks and kelp for example are shown. The Navigable Area Limit Lines (NALL) are represented by a red line that can be superimposed on the map. Any area closer to shore than the NALL is not required to be surveyed.

 

 

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The red line is the Navigable Area Limit Line. Areas inland of this line do not need to be surveyed, as they are known to be entirely non-navigable.

On occasion, surveying will discover a Danger to Navigation (DTON). This might include a rock close to the surface in a deeper water area that is not shown on any map and which may pose imminent danger to mariners. In these instances these dangers are reported upon return to the Fairweather, and information is quickly sent to the Marine Chart Division’s Nautical Data Branch.

During the course of the day, the scientists are constantly checking the data against a series of parameters than can affect its accuracy. Some of these parameters include temperature, salinity of the water and the tide levels. More about these parameters will be discussed in later blog postings.

Personal log

The first part of the day involves the stewards getting coolers of food ready for the survey crew who will be gone all day. The engineers have fixed any boat issues from the previous day and re-fueled the boats and the deck crew have them ready to re-launch. A GAR score is calculated by the coxswain and the crew, to determine the level of risk for the days launch. The GAR score examines the resources, environment, the team selection, their fitness, the weather and the mission complexity. Each factor is given a score out of 10. Added up, if the total is 23 or less, the mission is determined ‘low risk’, 24-44 is ‘use extra caution’, and greater than 45 is high risk. On the first day I went on a boat, as a first timer, the GAR score was a couple of points higher in the ‘team selection’ section as I was new.

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Operational Risk Assessment Form

Another fascinating aspect of this research is the equipment on the ship needed to launch these small boats. Huge winches are needed to hoist the boats in and out of the water. Deck crew, with support from the survey crew are responsible for the boat hauling multiple times a day, and the engineers are on hand to fix and monitor the equipment.

After my first day out on the small boats, the data acquisition began not only to make more sense, but also my understanding of the complex factors that make the data collection feasible began to broaden. I had naively assumed that all the work was done from the Fairweather and that the Fairweather would be constantly on the move, rather than being anchored in one location or so for a few days. As we journeyed around small islands covered in Sitka spruce, I watched constant communication between the survey crew and the coxswain on the small boats. The survey crew are constantly monitoring the chart and zooming in and out so that the coxswain can get a better and safer picture of where to take the boat.   As well as watching the monitors and driving the boat, the coxswain is also looking ahead and around for hazards. There is a significant number of large floating logs ready to damage boats, and on occasion, whales that the boat needs to stay away from. It is a long day for all the crew.

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Bekah and Sam monitor the incoming data to communicate quickly with Nick, the coxswain.

Aside from learning about the data acquisition being on the small boat, one of the joys was to be closer to some of the wildlife. While I will go in to more detail in later entries, highlights included catching glimpses of humpback whales, families of sea otters, and harbor seal pups.

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Yes, I got to drive…in the purple area.

Fact of the day: 

While animals, such as bats, have been using sonar for thousands or millions of years, it wasn’t until the sinking of the Titanic that sonar devices were invented and used for the locating of icebergs.  During World War I, a French physicist, Paul Langévin, developed a tool to be able to listen for submarines. Further developments lead to sonar being able to send and receive signals. Since then, major developments in sonar technology have led to many different applications in different science fields.

Word of the day: Nadir

On small boat surveys, nadir is the term used to describe the ocean floor directly below the boat. It is the low point below the boat.   

What is this?

What do you think this is a picture of? (The answer will be in the next blog installment).

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(Answer from previous blog: part of a section of a dumbbell from the Fairweather workout room)

 

Acronym of the Day

HIC: Hydrographer In Charge

 

 

 

 

 

 

 

 

 

 

 

Jason Moeller: June 25-27, 2011

NOAA TEACHER AT SEA
JASON MOELLER
ONBOARD NOAA SHIP OSCAR DYSON
JUNE 11 – JUNE 30, 2011

NOAA Teacher at Sea: Jason Moeller
Ship: Oscar Dyson
Mission: Walleye Pollock Survey
Geographic Location: Gulf of Alaska
Dates: June 25-27, 2011

Ship Data
Latitude: 55.58 N
Longitude: -159.16 W
Wind: 14.11
Surface Water Temperature: 7.2 degrees C
Air Temperature: 9.0 degrees C
Relative Humidity: 90%
Depth: 85.61

Personal Log
Anyone who has seen the show Deadliest Catchknows how dangerous crab fishing can be. Fishing for pollock, however, also has its dangers. Unfortunately, we found out the hard way. One of our deck hands caught his hand between a cable and the roller used to pull up the trawl net and hurt himself badly.

Cable

The cable and the roller.

Fortunately, the injuries are not life threatening and he will be fine. The injuries did require a hospital visit, and so we stopped at Sand Point to treat him.

Town

This is the town of Sand Point.

airstrip

Clouds hang over the hills at Sand Point. The airstrip is in the left edge of the photo.

We stayed at Sand Point for nearly 48 hours. What did we do? We fished, of course! We used long lines and hooks, and had a great time!

lines

Bill and Alex cast fishing lines in the harbor. We tied the lines off on the boat and hauled them up from time to time to check the bait.

Alex

Alex with a flounder that he caught! He also caught several cod and a 32-lb Pacific halibut!

cod

Cod and the flounder in a bucket!

Tammy

As with every fishing trip, we also managed to catch things that we didn't mean too! Tammy (the other NOAA Teacher at Sea) especially liked the kelp!

urchin

A few visitors always hitched a ride on the kelp we caught. Here is a tiny sea urchin.

crab

This crab was another hitchhiker on the kelp.

starfish

We were bottom fishing for Halibut, and a starfish, the largest one I've ever seen, went after the bait!

A one-day fishing license in Alaska costs $20.00. We had internet, so five of us went online and bought the fishing passes. Was it worth it?

Halibut

You bet it was! This is the 25-lb halibut I caught! It was AWESOME!!!

We filleted it and had the cooks make it for dinner. With the halibut, we also cut out the fleshy “cheeks” and ate them as sushi right on the spot! It doesn’t get any fresher (or tastier!) than that!

Science and Technology Log
Today we will look at the acoustic system of the Oscar Dyson! Acoustics is the science that studies how waves (including vibrations & sound waves) move through solids, liquids, and gases. The Oscar Dyson uses its acoustic system to find the pollock that we process.

The process begins when a piece of equipment called a transducer converts an electrical pulse into a sound wave. The transducers are located on the underside of the ship (in the water). The sound travels away from the vessel at roughly 1500 feet per minute, and continues to do so until the sound wave hits another object such as a bubble, plankton, a fish, or the bottom. When the sound wave hits an object, it reflects the sound wave, sending the sound wave back to the Oscar Dyson as an echo. Equipment onboard listens to the echo.

The computers look at two critical pieces of information from the returning sound wave. First, it measures the time that it took the echo to travel back to the ship. This piece of information gives the scientists onboard the distance the sound wave traveled. Remember that sound travels at roughly 1500 feet per minute. If the sound came back in one minute, then the object that the sound wave hit is 750 feet away (the sound traveled 750 feet to the object, hit the object, and then traveled 750 feet back to the boat).

The second critical piece of information is the intensity of the echo. The intensity of the echo tells the scientists how small or how large an object is, and this gives us an idea of what the sound wave hit. Tiny echos near the surface are almost certainly plankton, but larger objects in the midwater might be a school of fish.

good fishing

An image of the computer screen that shows a great number of fish. This was taken underneath the boat as we were line fishing in Sand Point.

poor fishing

The same spot as above, but with practically no fish.

fishing

An image of the screen during a trawl. You can actually see the net--it is the two brown lines that are running from left to right towards the top of the screen.

One of the things that surprised me the most was that fish and bubbles often look similar enough under water that it can fool the acoustics team into thinking that the bubbles are actually fish. This is because many species of fish have gas pockets inside of them, and so the readout looks very similar. The gas pockets are technically called “swim bladders” and they are used to help the fish control buoyancy in the water.

swimbladder

Swim bladder of a fish.

Species Seen
Northern Fulmar
Gulls
Cod
Pacific Halibut
Flounder
Sea Urchin
Crab
Kelp

Reader Question(s) of the Day
Today’s questions come from Kevin Hils, the Director of Chehaw Wild Animal Park in Chehaw, Georgia!

Q. Where does the ship name come from?
A. Oscar Dyson was an Alaska fisheries industry leader from Kodiak, Alaska. He is best known for pioneering research and development of Alaska’s groundfish, shrimp, and crab industry. Dyson was a founding partner of All Alaskan Seafoods, which was the first company actually controlled by the fishermen who owned the vessel. He also served on the North Pacific Fisheries Management council for nine years. He is in the United Fishermen of Alaska’s hall of fame for his work. The ship was christened by his wife, Mrs. Peggy Dyson-Malson, and launched on October 17, 2003.

Dyson

Oscar Dyson

launch

The launching of the Oscar Dyson

Q. How do you see this helping you teach at Knoxville Zoo, not an aquarium?
A. This will be a long answer. This experience will improve environmental education at the zoo in a variety of different ways.

First, this will better allow me to teach the Oceanography portion of my homeschool class that comes to the zoo every Tuesday. For example, I am in the process of creating a hands on fishing trip that will teach students about the research I have done aboard the Oscar Dyson and why that research is important. Homeschool students will not just benefit from this experience in Oceanography, but also in physics (when we look at sound and sonar) and other subjects as well from the technical aspects that I have learned during the course of the trip.

Scouts are another group that will greatly benefit from this experience as well. The Girl Scout council wishes to see a greater emphasis in the future on having the girls do science and getting real world experiences. While the girls are still going to desire the animal knowledge that the zoo can bring, they will also expect to do the science as well as learn about it. My experience aboard the Dyson will allow me to create workshops that can mimic a real world animal research experience, as I can now explain and show how research is done in the field.

The same can be said of the boy scouts.

In addition, one of the most common badges that is taught to boy scout groups that come in is the fish and wildlife merit badge. In the past, the badge has primarily focused on the wildlife aspect of this topic. However, I now have the knowledge to write and teach a fisheries portion for that merit badge, as opposed to quickly covering it and moving on. This will enrich future scouts who visit the zoo for this program.

A major focus for all scouts is the concept of Leave No Trace, where scouts are supposed to leave an area the way they found it. The fisheries research being done aboard the Dyson is focused toward that same goal in the ocean, where we are attempting to keep the pollock population as we found it, creating a sustainable fishery. The goal aboard the Dyson is similar to the goal in scouting. We need to be sustainable, we need to be environmentally friendly, and we need to leave no trace behind.

School children on field trips will greatly benefit, especially students in the adaptations section. There are some bizarre adaptations that I never knew about! For example, sleeper sharks slow, deliberate movement coupled with their fin and body shape basically make them the stealth fighter of the fish world. They can catch fish twice as fast as they are! Lumpsuckers are neat critters too! This knowledge will enhance their experience at the zoo during field trip programs.

Finally, I can pass the knowledge from this experience on to my coworkers. This will not only better the experience of my students, but it will also improve the outreach programs, the bedtime programs, the camps, and other programming done at the zoo.

Q. Are you old enough to be on a ship? You look like you’re 13???!!!!
A. SHHHHHHH!!!! You weren’t supposed to tell them my real age! They think I’m 24!

Tammy Orilio, Sand Point, Alaska, June 27, 2011

NOAA Teacher at Sea: Tammy Orilio
NOAA Ship Oscar Dyson
Mission: Pollock Survey
Geographical Area of Cruise: Gulf of Alaska
Date: 27 June 2011

Weather Data from the Bridge:
Latitude: 55.33 N
Longitude: -160.52 W

Wind Speed: 18.24 knots
Surface Water Temp: 7.3 degrees C

Water Depth: 28.43 m
Air Temp: 8.2 degrees C
Relative Humidity: 91%

Personal Log:
I woke up yesterday to the sound of the anchor being dropped (it’s a really loud noise that goes on for a few minutes). We weren’t scheduled to stop anywhere, so I figured something out of the ordinary had to be happening in order for us to be dropping anchor, and I soon found out what happened. Turns out a crew member had an accident onboard, so we headed to the nearest community to get to a medical facility, which is Sand Point- a small little fishing village.

So we ended up spending the day anchored in Sand Point yesterday. It was foggy & rainy yet again, so a few of the scientists purchased fishing licenses online and they fished off the back deck. They ended up catching some cod, halibut, and sculpins (Irish lords to be exact). They also ended up dragging some kelp up to the surface, and of course I was excited about that because I love seaweeds 🙂 And I’ve never seen live kelp in person before- I’ve only seen the dried stuff we ate in Marine 1!

Some buildings and a couple of windmills in Sand Point.

Some buildings and a couple of windmills in Sand Point.

A barge anchored in the bay.

A barge anchored in the bay.

Morning on 26 June 2011.

Morning on 26 June 2011.

A helicopter leaves the airport on 27 June. That spit of land is the runway.

A helicopter leaves the airport on 27 June. That spit of land is the runway.

Docks.

Docks.

We think this is Laminaria, but not positive.

We think this is Laminaria, but not positive.

Some kind of kelp. Salty.

Some kind of kelp. Salty.

We are still anchored here, because one of our science team members is going to fly out of here this afternoon to get to a meeting in Juneau. Sadly, our trip is essentially over- we are not going to do any more fishing 😦 I’m disappointed that the trip was cut a few days short, but the situation was out of everyone’s control, so there’s nothing I can do about it. I am thankful that I did get to go on this trip even if it was short- it was a great experience!

We’re supposed to be leaving Sand Point at some point this evening, and the weather forecast doesn’t look so good. High winds- up to 35 knots (that’s about 40 mph) and 18 ft seas are forecast for tonight, with only a little decrease for tomorrow. Going to be a great time!! I will definitely have to take my seasick medication before we leave here.

Question of the Day:

  • What kingdom & phylum are brown algae (such as kelp) in?

Susan Smith, June 4, 2009

NOAA Teacher at Sea
Susan Smith
Onboard NOAA Ship Rainier
June 1-12, 2009 

Mission: Hydrographic survey
Geographical area of cruise: Trocadero Bay, Alaska; 55°20.990’ N, 33°00.677’ W
Date: June 4, 2009

Weather Data from the Bridge 
Visibility: 10 nautical miles
Wind: light
Temperature 11.1 C (52 F)
Cloud Cover: FEW 1/8-2/8

A nautical chart indicating underwater cables

A nautical chart indicating underwater cables

Science and Technology Log: Bottom Sampling 

This morning I spent time in the Plot Room, and on the Fantail, involved in bottom sampling. The Plot Room has nine work stations with at least two screens per technician. The airplane symbol is the location of the Rainier and the colored dots show locations of bottom sampling areas. One purpose bottom sampling serves is to determine areas suitable for anchoring.

The clamp shell being retrieved

The clamp shell being retrieved

The chart to the right shows there is an underwater cable area (pink dotted lines) from which we cannot take samples, because it could accidently get damaged, thus rendering residents without power. The numbers shown on these When the ship takes bottom samples, from the Fantail, it uses a spring loaded clamp shell device. It is attached to an A frame and uses a winch to lower it into the sea by cable. The operator calls out the depth, using a cable counter, as it is lowered into the water and when it raised. This enables the plot room to know when a sample is coming and it verifies the information received remains accurate.  The numbers on these charts indicate water depth in fathoms (1 fathom=6 ft.). As you can see there are drastic dropoffs in some locations. 

Identifying the samples: small coarse pebbles

Identifying the samples: small coarse pebbles

If the cable is not straight down, the ship must move around it, avoiding the screws (propellers) at all costs. When the clamp hits bottom it scoops up the debris under it immediately and is brought back to the surface. When the sample arrives at the top it is shaken to release a majority of the water. Then it must be dismantled to see the solid matter inside. This is a two person job, as it is heavy and impossible to control for just one person. One holds the spring loaded clamp shell, the other takes off the sample section by pulling on either side of the device.

Identification chart for the samples

Identification chart for the samples

Because safety is always an issue the clamp must be kept from swinging once the collection unit is removed. The items found in the sampler are placed on the chart (shown to the right) to make sure identification is accurate. The chart is divided into sand, gravel, and pebbles. Each type of rock found is divided further into fine, medium, and coarse. This information is relayed to the plot room where someone labels the survey chart in the appropriate location. In the first four samples green, sticky mud was identified near the coastline of Ladrones Island, Madre de Dios Island, and on the southwestern arm of the Prince of Wales Island. These were deep areas where people are not likely to anchor their boats. In the sixth sample we were in fairly shallow water and sampled gritty sand and small pebbles.

This sample was full of sand and some pebbles.

This sample was full of sand and some pebbles.

Sometimes the water arrives only with living things in the sampler. Samples eight through ten provided us with living things. Shells with little creatures inside were found in one sampling, and in another the only item was a black sea star. Finally after three such samples in the same location we moved on to the next location. This is a somewhat tedious process when the samples do not provide a great deal of useful data. However, that in itself gives sufficient information as to what is NOT in a location. Now imagine being charged with this assignment is an area where surveys have either never been done, or it has been decades since the previous survey. Remarkably the survey charts are fairly accurate, even from when lead weights and ropes were used to survey. NOAA certainly has a daunting task when it comes to surveying Alaska.

Personal Log 

This sample had only a little black sea star!

This sample had only a little black sea star!

Yesterday, and today, allowed me the opportunity to see the technical aspects of the Rainier’s mission. Small sections of the oceans and bays are meticulously mapped and charted for use by recreational boaters, the fishing industry, large shipping companies, and the military. Without the information gleaned by the people and ships of the NOAA Corps our waters would continue to go uncharted, perhaps unused, and remain hazardous to all. I am amazed at the patience needed for this work, but it is well worth their efforts to provide the necessary tools to keep our waterways safe for everyone.

Jack on the bow

Jack on the bow

I was discussing interesting things I noticed on the Rainier with several of the officers. Did you know there are two flags we fly on the NOAA ships? There is the Jack, a flag with the 50 stars and blue field, and the Stars and Stripes, our nation’s flag. When it is flown on a ship it is called an Ensign. The Jack is flown on the Jackstaff (origin 1865-1895) located on the ship’s bow. The Ensign is flown on the fantail while in port or anchored at sea. I suppose I have now become a student of vexillology, the scholarly study of flags. 

Susan Smith, June 1, 2009

NOAA Teacher at Sea
Susan Smith
Onboard NOAA Ship Rainier
June 1-12, 2009 

Mission: Hydrographic survey
Geographical area of cruise: Trocadero Bay, Alaska; 55°20.990’ N, 33°00.677’ W
Date: June 1, 2009

NOAA Ship Rainier

NOAA Ship Rainier

Weather Data from the Bridge 
Sea Temperature: 10.0 C (50 F)
Visibility: Clear, 10+ nautical miles

Science and Technology Log 

What a way to start the day- learning how to deploy launches and all that goes into that process. Each new person onboard the ship who was going to be taking a launch, or responsible for their deployment, was required to attend this training meeting. Safety is of utmost importance on the NOAA ships and the smallest things when not done properly can result in disaster.

Coiling the throwing line

Coiling the throwing line

I learned a great deal of new vocabulary this morning, mostly pertaining to launch equipment, rope terms, and parts of the launch. It was stressed that in order for us all to have a positive experience we had to learn these terms and their procedures as quickly as possible.

Vocabulary: davit, lizard line, frapping line, bitter end, bite of line.

Tying off the Lizard line

Tying off the Lizard line

Three launches were deployed this afternoon to various areas around the Trocadero Bay. Using a Conductivity, Temperature and Depth(CTD) cast three times, we were able to determine salinity, depth of water, and temperature, all measurements used to calculate speed of sound. We set off to finish collecting data from areas missed, called “getting the holiday”. These are generally very small white areas on the screen which need to be surveyed. The wide pink line on the screen to the right indicates the section being surveyed. The pink section is actually made of many tiny lines as the sonar pings back to the launch.

Beautiful screen showing sonar return, most likely a rocky bottom. There are no breaks in the line, or acoustic shadows. The surveyors and techs really like this display of information.

Beautiful screen showing sonar return, most likely a rocky bottom. There are no breaks in the line, or acoustic shadows. The surveyors and techs really like this display of information.

This display is not so beautiful. The bottom was most likely mud or other soft bottom type, preventing a strong sonar return. The line with orange and   yellow dots under the bright green line is very weak and blurry. There are blank sections called acoustic shadows, or locations the sonar does not reach.

This display is not so beautiful. The bottom was most likely mud or other soft bottom type, preventing a strong sonar return. The line with orange and yellow dots under the bright green line is very weak and blurry. There are blank sections called acoustic shadows, or locations the sonar does not reach.

Animals Sighted: Red jellyfish, blue jellyfish, deer on the coastline

Personal Log 

Brown Kelp often deceives the sonar as it may appear as rocks.

Brown Kelp often deceives the sonar as it may appear as rocks.

What a grand time to be on a NOAA ship in Alaska! The weather has been fantastic, the scenery quite beautiful, and wonderful people who enjoy their jobs. Upon my arrival I was assigned “The PIT”, A C desk sleeping berth areas. It is below the laundry room, but very dark and surprisingly quiet considering its proximity to other mechanical areas of the ship. The suggested ear plugs were certainly a welcome item in the event I just couldn’t get to sleep.

Once I got my bearings, most of the areas I had to be in were easy to find. I was a little apprehensive that the onboard drills would be stressful, especially if I happened to be on the bridge or in the plot room. Going down three sets of steps, getting my survival suit, climbing back up one set of steps, and making it to my muster station as quickly as possible was not my idea of fun. However it was not as I imagined, as there were plenty of other new people who had to maneuver themselves around as well. Plus, we did not have to don the suits…this time!

Here I am working the sonar on a launch. Computer screens showing a vast array of data being collected and the charts used to record the data.

Here I am working the sonar on a launch. Computer screens showing a vast array of data being collected and the charts used to record the data.

As for the food…it is wonderful, as our cooks know what really drives the ship—a hunger-satisfied crew. And we get service with a smile, something not found in most public restaurants in this day and time. After my dinner Tuesday night I was able to go kayaking in the Trocadero Bay, located inside the Tongass National Forest. Never having done this activity before, I was quite excited to get going. Four of us took to the water for about two hours, kayaking around a large island. While sitting as still as the current would allow I was able to see quite a few seals pop their heads up, look around, then dive under again. Maybe we were infringing upon their recreation area!

Trocadero Bay

Trocadero Bay

 The view was spectacular, the water was calm, and I finally got to view a few eagles close enough to actually see the white feathers on their necks. Bird calls were also abundant. Such a nice way to end the day at sea.

Beth Carter, July 9, 2007

NOAA Teacher at Sea
Beth Carter
Onboard NOAA Ship Rainier
June 25 – July 7, 2007

Mission: Hydrographic Survey
Geographical Area: Gulf of Esquibel, Alaska
Date: July 9, 2007

Weather Data from Bridge 
Visibility:  6 miles
Wind direction:  135 degrees
Wind speed:  9 knots
Sea wave height: 0-1 feet
Swell wave height: none
Seawater Temperature:  12.2 degrees C
Dry Bulb: 11.1 degrees C  Wet Bulb:  11.1 degrees C
Sea level pressure:  1022.1 mb
Cloud cover: 8/8, fog & drizzle
Depth: 22.6 fathoms

This is a view of strands of kelp as seen from the launch.  Kelp appears as brown masses in thick beds.

This is a view of strands of kelp as seen from the launch. Kelp appears as brown masses in thick beds.

Science and Technology Log: 

Bull kelp…just amazing stuff.  Today I want to focus upon bull kelp and its role in the Alaskan coastal ecosystem, and its impact on hydrographers and fishermen. First of all…it is a fast-growing type of brown algae that can grow in strands from 40-65 feet long. It grows close into shore and anchors itself to rock surfaces by a root-like growth called a holdfast.  The scientific name is nereocystis leutkeana. Bull kelp has leaves called blades that grow outward from the main stem, but its most distinguishing feature is its long (2-3 feet) “bullwhip” stalks that have air bladders on their ends that can be 4” in diameter…rather like a stiff rope with a hollow onion on the end. Bull kelp can live for eight years, and reproduces via spores. Rocky substrates just off the coasts and islands of Alaska provide perfect places for the kelps’ holdfasts, and large kelp beds form in and around the islands of southeastern Alaska where the RAINIER is sailing.

In a closer view, bull kelp has some very stiff “bullwhip” like strands with air bladders on its ends.  The air bladders are hollow, and look like onions or bulbs.

Bull kelp has some very stiff “bullwhip” strands with hollow air bladders on the end that look like onions or bulbs.

Bull kelp provides food and protective cover for all types of fish, invertebrates, birds and marine mammals.  Kelp beds are literally teeming with life.  Kelp waves and moves with the currents and tides. Sea otters are the most visible of the animals who depend on kelp.  They feed off the sea urchins and other invertebrates that live at the bases of the kelp. Sea urchins feed upon the holdfasts that anchor the kelp, so the sea otters keep the urchins in check in a healthy kelp bed. The otters can be seen bobbing in the kelp, lying on their backs enjoying snacks of sea urchins, clams, etc. Commander Guy Noll of the RAINIER says that kelp is a natural navigational aid in Alaska and Pacific coastal waters. If you are in a boat of any kind and you see kelp strands on the surface of the water, stay clear. Hydrographers are not particularly fond of kelp.  On the one hand, the presence of kelp indicates a rocky bottom, which is one of the features that chartmakers want to indicate on their maps.  But.RAINIER’s launches try to stay out of kelp beds, as the kelp can become caught on the sonar transducers, which are suspended from the hulls of the boats. Kelp can also be a “heads up” that there may be a hidden rocky feature that is a danger to navigation.  The launches are very careful around kelp.

The sound waves that hydrographers use for charting can also be distorted by kelp, as it is very dense in its coverage. Also, the whips and floating blade “bladders are hollow, so the echoes do not reach the underlying rocky ground. NOAA sometimes has to send divers down to get a least depth in kelpy areas, and diving in kelp is difficult because of entanglement issues. Fishermen give kelp beds a wide berth to avoid fouling their nets and equipment in the heavy, leafy, stalky bull kelp. However, they will sometimes try to trawl near kelp beds, as the kelp provides excellent cover for salmon and other fish as they hide from orcas and other predators.

Small leaves, or blades of bull kelp washed into shore add decorations to the black pebble beaches.

Small leaves, or blades of bull kelp washed into shore add decorations to the black pebble beaches.

Personal Log 

I became fascinated by kelp last week as I kayaked through some island passages that were thick with kelp. As you look into the water, you see dozens, hundreds of small snails on the blades of the kelp…I think they were black turban snails.  I tasted some of the kelp and found it, predictably…salty!  It was also chewy and gummy and difficult to swallow. Perhaps there are wonderful ways to prepare kelp to eat, but out of the water as a snack – not for me. From the launches, it is fun to see the sea otters’ heads pop up in and near the kelp beds. They manage to get their heads and shoulders out of the water…they must be standing on the kelp to get such a clear look at us! Several of the moms we saw had babies hitching rides on their bellies, or perhaps nursing. They are unbelievably cute and quick, and I am too slow to get good photographs of them.

Correction! 

Early in the trip, I wrote about the GPS, Global Positioning Satellites, and stated that there are 11 in geosynchronous orbits above the earth.  I looked up GPS on the NOAA website and found that there are 24 satellites, so I stand corrected!

Questions of the Day

1. What do you think would be the environmental impact of an oil spill on or near the rocky coasts of Alaska?  

2. What effects would it have on kelp beds? If you want a real life example of what could and has happened, “Google” the story of the Exxon Valdez, which created a huge oil spill in Prince William Sound, Alaska in 1989.

* Note: Commander Guy Noll explained that the RAINIER was one of the responding vessels after the Valdez oil spill. RAINIER did the hydrographic work needed by the Navy ships that did the cleanup. At that time, the world’s focus turned upon Prince William Sound, and as the RAINIER did the surveying, they discovered many chart errors. They spent a great deal of time surveying the area, and provided more accurate charts for the cruise ships and tourists that became interested in the beautiful area in and around Prince William Sound.

This sea otter mom and baby are floating near a kelp bed. This photograph is courtesy of Ensign Tim Smith, an excellent officer and photographer on the RAINIER.

Sea otter mom and baby are floating near a kelp bed. Photograph courtesy of Ensign Tim Smith.