data collection – Page 2 – NOAA Teacher at Sea Blog

June 14, 2017June 14, 2017

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.

Launching small boat

Small boat off to start surveying

“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.

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.

3 sheets

Polygons within the ‘red’ sheet

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.

Beginning the data acquisition

Zoomed in and more coverage

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.

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.

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.

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.

fullsizeoutput_167 — 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.

fullsizeoutput_c0 — 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.

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).

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

Acronym of the Day

HIC: Hydrographer In Charge

September 25, 2016August 21, 2021

Denise Harrington: First Day Jitters, September 21, 2016

NOAA Teacher at Sea

Denise Harrington

Aboard NOAA Ship Oregon II

September 16-30, 2016

Mission: Longline Survey

Geographic Area: Gulf of Mexico

Date: Wednesday, September 21, 2016

My first day on the longline cruise seems so long ago with three days of work under my belt. The night before my first shift, just like when school starts, I couldn’t sleep. Trying to prepare was futile. I was lost, lost in the wet lab, lost in my stateroom, lost in the mess. I needed to get some gloves on and get to work, learning the best way I know how: by doing.

At noon, I stepped out the fantail, life vest, gloves, hard hat, and sunscreen on, nervous, but ready to work. The Gulf of Mexico horizon was dotted with oil rigs, like a prairie full of farmhouses. Heat waves rose from the black deck.

Dr. Trey Driggers baits the hooks.

TAS Denise Harrington baits hooks.

Fifteen minutes before arriving at our first station, our science team, Field Party Chief Dr. Trey Driggers, Field Biologist Paul Felts, Research Biologist Kevin Rademacher, NOAA Science Writer Matt Ellis, and I began to prepare for our first station by baiting the hooks with mackerel (Scomber scombrus). I learned quickly that boots and grubby clothes are ideal for this task.

p1080831 — Once all the hooks were baited, Chief Boatswain Tim Martin and Paul release a high flyer, a large pole with a buoy at the bottom and a reflective metal flag on top.

The buoy, connected to the boat by the longline, bobbed off toward the horizon.

Tim attached the first of three weights to anchor the line to the sea floor.

As the longline stretched across the sea, Kevin attached a numbered tag to the baited hook held by Paul.

Paul passed the baited, tagged hook to Tim, who attached 100 hooks, evenly spaced, to the one mile longline.

p1080838 — On another station, Paul attached numbers to the gangion (clip, short line, and baited hook) held by Trey. Each station we change roles, which I appreciate.

Setting the longline is rather predictable, so with Rush and Van Halen salting the air, we talked about our kids, dogs, riots in the news, and science, of course. The tags will help us track the fish we catch. After a fish is released or processed, the data is entered in the computer and shared with the scientific community. Maybe one of these tagged fish will end up in one of the many scientific papers Trey publishes on sharks each year.

The line soaked for an hour waiting for snapper, tilefish, eels, sharks, and other fish to bite. While the line soaked, Mike Conway, skilled fisherman, and I lowered the CTD, a piece of equipment that measures conductivity (salinity), temperature, and depth, into the water. Once the biologists know how salty, cold, and deep the water is, they can make better predictions about the species of fish we will find.

Denise and Mike lower the CTD.

Styrofoam cup comparison

We attached a bag holding a few Styrofoam cups to see how the weight of the water above it would affect the cup. Just imagine the adaptations creatures of the deep must have developed to respond to this pressure!

The ship circled back to hook #1 to give each hook equal time in the water. After an hour, we all walked up to the well deck, toward the bow or front of the ship. We pulled in the first highflyer and weight. We pulled in the hooks, some with bait, and some without. After 50 hooks, the middle weight came up. We still didn’t have a fish. I began to wonder if we’d catch anything at all. No data is still data, I thought. “Fish on eighty three!” I heard someone yell. I wake from my reverie, and get my gloves on.

It was a blacknose shark (Carcharhinus acronotus), “pound for pound, the meanest shark in the water,” says Trey. He would know, he’s the shark expert. It came up fighting, but was no match for Kevin who carefully managed to get length, weight, and sex data before releasing it back into sea.

Kevin measures the shark’s length in millimeters, Paul takes records the data, and Matt takes photos.

Then Kevin weighs it in kilograms.

With one shark to process, the three scientists were able to analyze the sexual maturity of the male blacknose together. I learned that an adult male shark’s claspers are hard and rotate 180˚, allowing them to penetrate a female shark. An immature shark’s claspers are soft and do not rotate. For each male shark, we need to collect this data about its sex stage.

p1080172 — Here, you can see Trey rotating the clasper 180 degrees.

Later, Paul talked about moments like these, where the field biologists work side by side with research biologists from all different units in the lab. Some research biologists, he notes, never get into the field. But Kevin, Trey, and others like them have a much more well-rounded understanding of the data collected and how it is done because of the time they spend in the field.

Fortunately, the transition from inexperienced to novice was gradual. The second line was just as easy as the first, we only brought in two fish, one shark and one red snapper (Lutjanus campechanus).

Dissection Photos: Matt Ellis/NOAA Fisheries

For the red snapper, we removed the otoliths, which people often call ear bones, to determine age, and gonads to determine reproductive status. I say “we” but really the scientists accomplished this difficult feat. I just learned how to process the samples they collected and record the data as they dissected the fish.

We set the longline a third time. The highflyer bobbed toward the orange sun, low on the horizon. The ship turned around, and after an hour of soaking, we went to the well deck toward the front of the ship to pull in the longline. The sky was dark, the stars spread out above us.

“One!” “Three!” “Seven!” “Nine!” The numbers of tags with fish on the line were being called out faster than we could manage. It seemed like every other hook had a shark on it. Two hours later we had collected twenty-eight Atlantic sharpnose (Rhizoprionodon terraenovae) sharks and had one snapper to process. Too busy working to take pictures, I have nothing to document my transition from inexperienced to novice except this data sheet. Guess who took all this data? Me!

Personal Log

NOAA Ship Oregon II is small, every bunk is filled. I share a stateroom with the second in command, Executive Officer (XO) Lecia Salerno, and am thankful she is such a flexible roommate, making a place for me where space is hard to come by.

Last night, as I lay in my bunk above XO Salerno and her office, I felt like Garth on Wayne’s World, the thought that “I’m not worthy” entering my head. All members of the crew are talented, experienced, and hard-working, from the bridge, to the galley, to the engine room, and out on the deck where we work. I’ve made a few mistakes. I took the nasty thought and threw it overboard, like the slimy king snake eels (Ophichthus rex) we pull from the deep.

o-rex — King Snake Eel (*Ophichthus rex*)

In the morning I grabbed a cup of coffee, facing the risk of being the least experienced, slowest crew member to learn, with curiosity and perseverance. First day jitters gone, I’m learning by doing.

May 31, 2015August 21, 2021

Alex Miller: Smooth Sailing So Far, May 31, 2015

NOAA Teacher at Sea
Alexandra (Alex) Miller, Chicago, IL
Onboard NOAA Ship Bell M. Shimada
May 27 – June 10, 2015

View of the Hatfield Marine Science Center and NOAA dock as the Shimada pulled away.

Mission: Rockfish Recruitment and Ecosystem Assessment
Geographical area of cruise: Pacific Coast
Date: Sunday, May 31, 2015

Weather Data:

Air Temperature: 11.1°C
Water Temperature: 11.8°C
Overcast skies
Wind Speed (kts) and Direction: 15, SSE

Science and Technology Log

Last of the bridge we'll see for some time. — Last of the bridge we’ll see for some time.

We finally weighed anchor and set sail at 1032 Friday morning. Fog blanketed the shores of Newport as we passed below the Yaquina Bay Bridge and out into the channel created by the North and South Jetties. One of our last sights from shore was Chief Scientist Ric Brodeur’s wife, who had come to see us off. The fog was so thick that before we had even reached the end of the jetty her lime green jacket was hidden from view.

Emily and I and several of the other scientists watched our departure from the flying bridge, the highest observational deck on board the ship. It provides an almost unobstructed 360-degree view of the surroundings—making it perfect for Amanda’s surveys—but it’s also right next to the foghorn, which had to be blown every two minutes until we reached greater visibility. Needless to say, we all found somewhere else to watch the waves.

Once the ship had moved farther offshore, some of the fog cleared but the moisture in the air was still enough to cause concern for the computers so Amanda went to the bridge, an enclosed deck that houses the navigational instruments that the captain and other officers use to drive the ship. Here she began setting up her survey equipment.

Up to this point, I’d been getting a lot of great advice about handling the first few hours on board the moving ship. Some people suggested I lay down, but the go-getter in me wanted to work. Using a program that is linked to the ship’s GPS, Amanda taught me how to code the observations she was making of the seabirds and marine mammals. As she kept her eyes glued on the 90-degree quadrant made by making a quarter port (while facing the front of the ship, counter clockwise or left, for you digital folks) turn from the bow (front of the ship) (in the image at the top of this post, you can see a panoramic view of quadrant I, the port bow of the ship), she would call out codes for the species, distance from the ship and behavior of the bird she observed. If she were to spot any marine mammals–pinnipeds (pin-eh-peds) (seal and sea lions) or cetaceans (ceh-tay-shins) (dolphins and whales)–that gets entered in a separate database.

Amanda surveying from the flying bridge.

Amanda has to be prepared to work alone as she is the only ornithologist on the ship, but with a Teacher at Sea and other volunteers on board willing to learn and help out, she’s able to rely on us to share some of the work. She and I were working as quite the well-oiled machine for a solid 20 minutes before I made peace with the fact that I did not have my sea legs. To my great relief, it’s something you can sleep off.

__________________________

While at sea, the most important thing to remember is to be safe, so once we had been underway for a few hours, the ship’s crew and team of scientists went through drills to practice safety protocols for two of the three significant events that could happen at sea. A 10-second blast on the horn sounded the alarm for the fire drill, and all crew and scientists mustered (gathered) in their assigned locations. Next, 7-short, and 1-long blast signaled the start of the abandon ship drill. The need to abandon ship is highly unlikely, but out at sea you need to be prepared for anything. Most importantly, you need to know how to get into your survival suit, and fast.

Emily and I decided to practice since we were both first-timers to these impressive red neoprene onesies. Since they’re designed to be large enough to fit over your shoes and warm clothes, they can be awkward to put on, especially when you get to the zipping part. And who cares how they look when the water is 8-10° Celsius, a temperature that could cause hypothermia or fatal loss of body temperature.

Emily and I managed to get the survival suits on!

__________________________

Saturday was spent sampling a little bit of everything. Of course I paid a visit to Amanda up on the flying bridge to hear about how the birding (and marine mammal-ing) was going. Often, I find Emily there assisting with data entry. Since Amanda can only survey when the ship is traveling faster than 7 knots, traveling from station to station gives her time to look, but sometimes these distances are short and our time at the stations, releasing the various equipment needed for different scientists’ data collection, can be long. This is when Amanda goes off effort (not collecting data) for longer periods of time and during these times, Emily and I have taken to teaming up to check out what’s going on in the wet lab.

Jaclyn releases the neuston tow into the water.

Home to most of the science crew, the wet lab is wet. Initially, I thought foul weather gear was meant for, well, foul weather, but between the hauling in, spraying down and rinsing of the samples caught in the nets, everyone in the wet lab is wearing theirs full-time. Also, everyone must wear hard hats and PFDs (personal flotation devices, also known as life jackets) when out on deck as the equipment is being released or hauled in. Safety first, as always!

My cabin mate, Jaclyn Mazzella, and Phil White, are the two survey technicians on the Shimada. They help release and monitor the nets and equipment that are being used on this research cruise. More on these two interesting cats later.

Emily and I working hard to haul in the CTD.

While in the wet lab, Emily and I witnessed the CTD being hauled in. CTD stands for conductivity, temperature and depth. Conductivity is a measurement of salinity, or how salty the ocean water is. The way it works is by passing an electric current through the water and measuring how fast it travels. This is connected to how salty the water is because when salt is dissolved in water, it separates into ions, these particles carry a charge and allow electric current to pass through. More conductive water will be salty, less conductive water will be less salty or fresh.

We know that temperature provides a measurement of how hot or cold something is. In this case, we’re measuring the temperature of the water. It is mostly cold off the Oregon coast, though the scientists on board have been discussing a recent unexplained area of warmer water, dubbed the “warm blob.” Biologists aim to discover if the warm blob is going to have an impact on the fisheries.

As the CTD is lowered and raised, it can take measurements of these and other factors which allow biologists to compare the diversity and number of species they collect in their nets to the data collected. One of those nets is the neuston tow, a net that skims the surface of the water. It is one of several nets that are being used to collect samples from different layers of the ocean. The scientists on board expect to find jellies and larvae of different species in this net.

Curtis filters the cod-end of the neuston and finds a whole bunch of Vallela vallela. — Curtis filters the cod-end of the neuston and finds a whole bunch of Vellela vellela.

I got a chance to see the neuston being released. After it was hauled in, Dr. Curtis Roegner, a fisheries biologist with NOAA, detached the cod-end–a small container at the bottom of the net that collects everything the net caught–and filtered out the contents. Inside were a bunch of beautiful blue jellies! These guys are commonly known as by-the-wind sailors thanks to their interesting sail adaptation that allows them to harness the power of the wind to aid in their dispersal (scattering) throughout the ocean. I helped Sam Zeman, a biologist with the University of Oregon, Tyler and Curtis measure the diameter–the length at the widest point–of the bodies of the jellies.

Vallela vallela, by the wind sailors. — Vellela vellela, by the wind sailors.

Curtis, Tyler and I working to measure and record the lengths of the sails on the Vallela vallela. (Thanks to Sam for taking this picture!) — Curtis, Tyler and I working to measure and record the lengths of the sails on the Vellela vellela. (Thanks to Sam for taking this picture!)

Personal Log

The more time I spend on the Shimada, the more determined I am to figure out how time travel works so I can go back and thank my September 2014 self for putting in the Teacher At Sea application. I’ve been on the ship for three days now and I love being able to go anywhere, day or night, and be able to observe and assist in research and data collection, but also just sit and talk with people who have all followed many different paths that led them to this ship, for these two weeks.

You might think my biggest struggles right now would be seasickness (which I’m not!) or missing my friends and family, but honestly, the hardest part is keeping the blog down to a readable length. There’s an enormous amount more happening here than I have the room to tell you but I will try and cover everything before our time is up.

Lastly, it’s true, I miss my friends and family, a lot, but there are certain creature comforts here that help ease the transition from land to sea. NOAA certainly knows how to keep morale and productivity up, with a well-stocked kitchen open 24 hours, meals prepared on site by talented cooks, and a TV lounge for socializing with a selection of over 500 movies, it’s easy to feel at home. And when finding a work-life balance is not possible, it’s necessary, all of this helps.

Well, that’s all for now, catch the next installment coming soon to a computer screen or mobile device near you!

Acknowledgements

Special thanks to Prof. Mary-Beth Decker consulting on the spelling of Vellela vellela and Brittney Honisch for teaching me a good way to remember port vs. starboard. When facing the front of the ship, port is left and both words have four letters.

July 12, 2013August 13, 2021

Jennifer Petro: Diving into the Deep, July 10, 2013

NOAA Teacher at Sea
Jennifer Petro
Aboard NOAA Ship Pisces
July 1 — 14, 2013

Mission: Marine Protected Area Surveys
Geographic area of cruise: Southern Atlantic
Date: July 10, 2013

Weather Data
Air temperature: 28.4°C (81.5°F)
Barometer: 1010.20 mb
Humidity: 76%
Wind direction: 103°
Wind speed: 1.5 knots
Water temp: 27.5° C (81.5°F)
Latitude: 32 81.67 N
Longitude: 78 12.95 W

Science and Technology Log

The most integral piece of equipment on board is the ROV. A Super Phantom S2 to be precise. The ROV is operated by the team of Lance Horn and Glenn Taylor from the University of North Carolina, Wilmington (UNCW). Dubbed by me as the “ROV Guys”, Lance and Glenn have almost 50 years of combined experience working on and operating ROVs. The Super Phantom S2 is part of UNCW’s Undersea Vehicle Program which currently consists of 2 ROVs and 1 Autonomous Underwater Vehicle or (AUV). In the fall they will be adding a third ROV to their fleet. The ROV set-up is quite impressive and centers around one key component….communication. The ROV is tethered to the ship by an umbilical. During each and every dive the ROV operator is in constant contact with the ROV deck. The umbilical is either payed out over the side or brought back in according to the dive depth and that needs to also be communicated to the wench operator. The ROV deck is constantly watching the direction and tautness of the umbilical so that it does not get overstretched or goes into the boat’s prop. All the time the ROV driver is in contact with the bridge. So, there is a lot of communication and it is integral in every aspect of ROV operations.

Not only are all of the people involved in ROV ops communicating but the ROV and boat are communicating

as well. The ROV uses an integrated navigation system to provide real-time tracking of the ROV and ship to the ROV operator and the Pisces bridge for navigation. Ship and ROV positions with ROV depth, heading and altimeter reading are logged for each dive and provided to the scientist in an Excel file. Geo-referenced .tif files can be used as background files to aid in ROV and support vessel navigation.

The vessel has a machine shop which allowed the ROV guys to fox the transducer early in the cruise. — The vessel has a machine shop which allowed the ROV guys to fix the transducer early in the cruise.

The front of the ROV showing spot lights and camera arrays. — The front of the ROV showing spotlights and camera arrays.

The ROV can go to a depth of approximately 305 meters (1000 ft). Our deepest dive on this cruise is 200 meters (650 ft) which is 20 atm of pressure! What does that mean? At sea level, the weight of all the air above you creates one “atmosphere” (atm) of pressure equivalent to 14.7 pounds pressing on each square inch. In the ocean, the pressure increases very rapidly with depth because water is much denser than air. For every 33 feet (10 meters) of depth, the pressure increases by 1 atmosphere. So at 20 atmospheres there is a lot of pressure pushing down on all sides. It is the increase in pressure that makes it difficult to do manned deep water dives and one of the reasons why the use of ROVs is so important.

As an experiment we sent styrofoam cups that we had decorated in a bag along with the ROV down to a depth of 170 meters 550 ft. The cups shrink due to the increased pressure of the water. The deeper you go the more they will shrink.

Styrofoams cups. Before and after being sent down with the ROV.

Data collection: Data is collected during each dive by the means of video recording and still camera photos. Each camera is in a special pressure rated, water proof housing. There is special attention given to the 7 target species (5 of which we have recorded this cruise) as well as any new or interesting species that we have seen. This data is analyzed back in the lab. So far we have approximately 64 hours of video and 2400 still photos. Needless to say reviewing the data is time-consuming but a very important aspect in confirming what we see during the actual cruise.

Still photos taken with the ROVs Nikon CoolPics camera.

Photos taken by the still camera of the UNCW Super Phatom ROV. — Photos taken by the still camera of the UNCW Super Phantom ROV.

Driving the ROV is much like playing a video game, only you have many more screens you have to monitor. I did get an opportunity to drive it over sand! According to Lance it takes about 20 hours of training to learn to drive effectively drive the ROV. There are no simulations, all of the drive time is hands-on and in the water.

Lance Horn giving me pointers on how to keep the ROV level and on course.

Personal Log

While I was in the Acoustics Lab speaking with the folks that do the multibeam mapping, I looked down at the probes that they use and a single word jumped out at me: “Sippican”. I know this word from my childhood. We used to visit my Aunt Carol and Uncle Al in Marion, Massachusetts which sits on Sippican Harbor off of Buzzards Bay. Sure enough the probes are made by Lockheed Martin Sippican, Inc. located in Marion, MA. This struck me as so apropos. My Uncle Al was a marine biologist and started a research lab in Falmouth, MA. I would go to the lab with him and count flounder larvae for hours on end. He was very instrumental in developing my love for marine science and I was overjoyed to have a connection, albeit small, to a man whose work I admired very much.

July 8, 2013August 13, 2021

Amie Ell: Fireworks, Fish, and Flukes, July 6, 2013

NOAA Teacher at Sea
Amie Ell
Aboard NOAA Ship Oscar Dyson (NOAA Ship Tracker)
June 30 – July 21, 2013

Mission: Alaska Walleye Pollock Survey
Geographical Area: Gulf of Alaska
Date: July 6th, 2013

Location Data from the Bridge:
Latitude: 55.29.300 N
Longitude: 156.25.200 W
Ship speed: 10.7 kn

Weather Data from the Bridge:
Air temperature: 8.6 degrees Centigrade
Surface water temperature: 8.6 degrees Centigrade
Wind speed: 14 kn
Wind direction: 210 degrees
Barometric pressure: 1008.5 mb

Science and Technology Log:

The Oscar Dyson is equipped with several labs to accommodate the researchers on board. In this blog post I will describe to you what is happening in the wet/fish lab. This is where I have experienced quite a bit of hands-on data collection.

Pollock being separated on the conveyor belt.

After a trawl, the crew dumps the load of fish into a bin. Inside the lab we can raise or lower this bin to control the amount of fish coming onto a conveyor belt. Once the fish are on the belt the scientists decide how they will be separated. We separate the pollock according to age into baskets. They are categorized by size; under 20 cm (age 1), under 30 cm (age 2), and any larger than 30 cm

At this time we also pull out any other sea creatures that are not pollock. So far we have pulled up quite a few jelly fish, la lumpsucker, shrimp, squid, eulachon, and capelin. These are also weighed, measured, and in some cases frozen per request of scientists not currently on board.

After organizing the pollock into appropriate age groups, we then measure and record their weight in bulk. Scientists are using a scale attached to a touch screen computer with a program called CLAMS to record this information. The pollock are then dumped into a stainless steel bin where their sex will be determined. In order to do this the fish must be cut open to look for “boy parts, or girl parts”. After the pollock are separated into female and male bins we begin to measure their length.

This is the tool used for measuring length of the fish.

The tool used to measure length is called the Ichthystick. This tool is connected to the CLAMS computer system. The fish is placed on the Ichthystick and a pointer with a magnet in it is placed at the tail end of the fish. There are three different types of length measurement that can be done: fork length, standard length, and total length. When the magnetic pointer touches the Ichthystick it senses that length and sends the information to the CLAMS computer system.

One of these bins of fish is placed aside for individual weighing, length measurements, and removal of otoliths. You may recall that I mentioned otoliths in the last blog post. These ear bones are sent to a lab and analyzed to determine the age of each of these individually measured fish. The Alaska Fisheries Science Center has created a demonstration program where you can try to determine the age of different types of fish by looking at their otoliths. Click here to try it yourself! (I will add hyperlink to: http://www.afsc.noaa.gov/refm/age/interactive.htm)

Personal Log:

One afternoon while waiting for the fishermen to bring up the trawl net, I watched a group of porpoises swimming behind the ship. Another day I was able to see whales from up on the bridge. These were pretty far out and required binoculars to see any detail. I observed many spouts, saw one breach, and some flukes as well.

There is quite a bit of downtime for me on the ship while I am waiting in between trawls. I get to read a lot and watch movies in my free time. I have had the opportunity to talk with different members of the crew and learn about their roles a bit. The chief engineer gave me a tour of the engine rooms (more about this with pictures in a future post.)

The 4^thof July fireworks show on the Oscar Dyson was like no others I have ever experienced. Two of our crew, Ben & Brian, dressed in official fire gear shot expired flares off the ship into the sea. America themed music was played over the PA system. I have attached a video of our fireworks display. Happy Independence Day everyone!