Pam Schaffer: Oceanographers Toolbox: What is a CTD? July 7,2018

NOAA Teacher at Sea

Pam Schaffer

Aboard NOAA Ship Bell M. Shimada

[July 2-10, 2018]

Mission: ACCESS Cruise

Geographic Area of Cruise: North Pacific:  Greater Farallones National Marine Sanctuary, Cordell Bank National Marine Sanctuary

Weather Data from the Bridge

Date July 7 2018
Time 1200  (noon)
Latitude 37° 58.3’ N
Longitude 123° 06.4’ W
Present Weather/ Sky Cloudy
Visibility (nm) 10
Wind Direction (true) 341°
Wind Speed (kts) 18
Atmospheric Pressure (mb) 1018
Sea Wave Height (ft) 3-5
Swell Waves Direction (true) 330°
Swell Waves Height (ft) 3-5
Temperature  Sea Water (C) 13.2°
Temperature Dry Bulb (C)

Air Temperature

13.1°
Temp Wet Bulb (C ) 12.1°

 

Science and Technology Log

Marine life is not evenly distributed throughout the World’s oceans.  Some areas contain abundant and diverse life forms and support complex food webs whereas other areas are considered a desert.  This variation is due to environmental factors like temperature, salinity, nutrients, amount of light, underlying currents, oxygen levels and pH.  Some of these variables, such as temperature, oxygen levels, and pH, are experiencing more variability as a result of climate change.  In order to understand the health of marine environments, scientists explore the chemical and physical properties of seawater using a set of electronic instruments on a device called a CTD.   CTD stands for conductivity, temperature and depth and is the standard set of instruments used to measure variables in the water column.

Source: ACCESS www.ACCESSoceans .org

Source: ACCESS http://www.ACCESSoceans .org

The CTD is the bread and butter of oceanography research. It is primarily used to profile and assess salinity and temperature differences at varying depths in a water column.  But the device can also carry instruments used to calculate turbidity, fluorescence (a way to measure the amount of phytoplankton in the water), oxygen levels, and pH.  Conductivity is a way of determining the salinity of water. It measures how easily an electric current passes through a liquid.  Electric currents pass much more easily through seawater than fresh water.  A small electrical current is passed between two electrodes and the resulting measurement is interpreted to measure the amount of salt and other inorganic compounds in a water sample. Dissolved salt increases the density of water, and the density of water also increases as temperature decreases.  Deeper water is colder and denser.  Density is also affected by water pressure. Since water pressure increases with increasing depth, the density of seawater also increases as depth increases.

Optical sensors are used to measure the amount of turbidity, fluorescence, and dissolved oxygen at various depths in the water column.  Dissolved oxygen levels fluctuate with temperature, salinity and pressure changes and is a key indicator of water quality.  Dissolved oxygen is essential for the survival of fish and other marine organisms.  Oxygen gets into the water as gas exchange with the atmosphere and as a by-product of plant photosynthesis (algae, kelp etc.).

Photo Credit: Julie Chase/ACCESS/NOAA/Point Blue

Photo Credit: Julie Chase/ACCESS/NOAA/Point Blue

Typically, CTD instruments are attached to a large circular metal frame called a Rosette, which contains water-sampling bottles that are remotely opened and closed at different depths to collect water samples for later analysis. Using the information and samples collected, scientists can make inferences about the occurrence of certain chemical properties to better understand the distribution and abundance of life in particular areas of the ocean.

Scientist Carina Fish collects samples from CTD

Scientist Carina Fish collects samples from CTD

On our mission, scientists deploy the CTD to a depth of 500 meters at most stations. On the shelf break, the researchers deployed the CTD to 1200 meters (more than 3/4 of a mile below the surface) to collect samples.    The pressure is so great at this depth that a 1 foot by 1 foot square of Styrofoam is crushed to a quarter of its size(3″x 3″).

Retrieving the CTD Rosette

Retrieving the CTD Rosette

Personal Log

Around 01:30 last night we lost our Tucker Trawl net as it was being re-positioned.  The winds had picked up to around 20 knots and the sea height was around 5-8 feet according to the bridge log.   The sea state complicated the retrieval and as best we can conclude the wind and seas pushed the net bridle into a prop blade which swiftly and effortlessly cut the 1/3” thick metal wire cable and separated the net from its tether.  Mishaps at sea are part and parcel of working in a harsh and variable environments. Even the very best and most experienced captain and crew encounter unforeseen issues from time to time.   Dr. Jaime Jahncke quickly stepped into action and made contact with onshore colleagues to arrange for another net for the next research cruise.   In the meantime, we plan to use the hoop net to collect krill samples, weather permitting.

Did You Know?

According to NOAA scientists, only about 5% of the Earth’s oceans have been explored.

Angela Hung: “The Solution to Pollution is Dilution”, July 3, 2018

NOAA Teacher at Sea

Angela Hung

Aboard NOAA Ship Oregon II

June 27-July 5, 2018

 

Mission: SEAMAP Summer Groundfish Survey

Geographic Area of Cruise: Gulf of Mexico

Date: July 3, 2018

 

Weather Data from the Bridge

Conditions at 1610

Latitude: 29° 30’ N

Longitude: 92° 51’ W

Relative Humidity: 83%

Temperature: 26° C

Wind Speed: 13 knots

Cloudy with rain

 

Science and Technology Log

“The solution to pollution is dilution” was a common refrain during the midcentury as large scale factories became more common. This mindset applied to both air and water as both seemed limitless. Looking out over the Gulf of Mexico, a relatively small body of water, it’s easy to see how this logic prevailed. Even the Great Lakes, the largest body of fresh surface water in the world, accepted incalculable amounts of pollution and sewage from coastal factories, steel and wood mills, and of course major cities.

Sky and water as far as the eye can see. (It's hard to take a steady shot on a rocking boat!)

Sky and water in the Gulf of Mexico as far as the eye can see from the deck of NOAA Ship Oregon II. (It’s hard to take a steady shot on a rocking boat!)

The rise of the modern technological age that took humans to the moon gave us the first glimpse of the fallacy of the “solution”. “Earthrise” is the first photo of the entire Earth taken from space, showing us how thin our protective atmosphere really is and how delicately the Blue Planet floats in the vastness of space. This is the beginning of the modern environmental movement.

"Earthrise" Photo courtesy of nasa.gov

“Earthrise” Photo courtesy of nasa.gov

To truly guide the development of national policies including those that protect air and water quality, federal agencies such as NOAA are responsible for collecting data about our atmosphere and oceans, now knowing that these ecological compartments cannot endlessly dilute the pollution we generate. What seemed to be an obvious solution has today ballooned into a number of serious problems, from acid rain and blinding smog in cities to burning rivers, mass fish die offs that wash up on Lake Michigan beaches and dying coral reefs in the oceans.

The Cuyahoga River that runs through Cleveland, OH caught fire over a dozen times. This fire in 1969 finally motivated action towards creating the Clean Water Act.

The Cuyahoga River that runs through Cleveland, OH caught fire over a dozen times. This fire in 1969 finally motivated action towards creating the Clean Water Act. Photo from: https://www.alleghenyfront.org/how-a-burning-river-helped-create-the-clean-water-act/

A major pollutant in the Gulf is sourced from industrial agriculture practices from as far away as Illinois and the rest of the Midwest farm belt. Fertilizer and pesticides enter local rivers that find their way to the Mississippi River which carries contaminants into the Gulf of Mexico.

We have reached the Gulf’s “Dead Zone”, yielding a few tiny catches. Station W1601 may have given the smallest catch ever—a clump of seaweed and a whole shrimp.

The case of the shrinking trawls. On left, a catch from the night of July 2. Center and right, samples from two stations in hypoxic waters. The fish in the right photo may have been stuck in the net from the previous trawl.

The case of the shrinking trawls. On left, a catch from the night of July 2. Center and right, July 3 samples from two stations in hypoxic waters. The fish in the right photo may have been stuck in the net from the previous trawl.

Hypoxia literally means “low oxygen”. When fertilizers used to grow corn and soy enter bodies of water, they likewise feed the growth of algae, which are not technically plants but they are the aquatic equivalent. But plants make oxygen, how can this lead to low oxygen? Algae and land plants only produce oxygen during the day. At night, they consume oxygen gas through respiration. They do this during the day as well, but overall produce more oxygen in the light through photosynthesis. For hundreds of millions of years, that’s been fine, but the recent addition of fertilizers and the warm Gulf waters cause an explosion of the kind of microscopic algae that are suspended in the water column and turn water bright green, or red in the case of “red tides”. These explosions are called algal blooms.

Algal blooms can cloud up water, making life hard for other photosynthetic organisms such as coral symbionts and larger seaweeds. At night, animals can suffocate without oxygen. During red tides, some algae release toxins that harm other life. When these organisms die and sink, bacteria go to work and decompose their bodies. The population of bacteria explodes, consuming the remaining oxygen at the sea floor. Animals that wander into the hypoxic zone also suffocate and die, feeding more decomposer bacteria that can survive with little to no oxygen. Thus, hypoxic areas are also called “dead zones”.  The hypoxic zone is just above the sea floor, as little as a half a meter above, and oxygen levels can drop precipitously within a meter of the bottom.

NOAA scientists including those conducting the SEAMAP Summer Groundfish survey on Oregon II track the location, size and movement of the Gulf hypoxic zone using the conductivity-temperature-dissolved oxygen probe, or CTD. The CTD is sent into the water before every trawl to take a variety of measurements. Besides conductivity (a measure of ions), temperature and oxygen, the CTD also checks the salinity, clarity and amount of photosynthetic pigments in the water, which gives an idea of plankton populations. Ours uses two different sensors for conductivity, salinity, temperature and oxygen, double-checking each other. A pump pulls water through the various sensors and the measurements are sent directly to a computer in the dry lab to record these data.

The CTD is lowered to just under the surface of the water to make sure the pump is working and to flush the system. Then it is lowered to within a meter of the bottom. The CTD also has an altimeter to measure the distance from the bottom, while the ship also uses sonar to determine the water depth at each station. Water is measured continuously as the CTD is lowered and raised, creating a graph that profiles the water column. Crewmen are on deck controlling the winches according to the directions from a scientist over the radio who is monitoring the water depth and measurements in the dry lab.

Conductivity, temperature, dissolved oxygen sensor (CTD). The gray cylinders are bottles that can store water samples.

Conductivity, temperature, dissolved oxygen sensor (CTD). The gray cylinders are bottles that can store water samples.

Casting the CTD is a coordinated effort.

Casting the CTD is a coordinated effort.

The CTD also has bottles that can store water samples so oxygen can be tested a third time in the lab onboard. When we only get a few fish where the CTD recorded normal oxygen, the CTD is launched again to verify oxygen levels using all three methods. In the CTD output, oxygen is coded in green as a line on the graph and in the data tables. Most stations read in the 5-6 range, the cutoff for hypoxia is 2. We are reading less than 1 in the Dead Zone.

CTD output. Depth is on the vertical axis and each measurement is scaled on the horizontal axis, showing how each variable changes as the CTD moves to the bottom and back to the surface.

CTD output. Depth is on the vertical axis and each measurement is scaled on the horizontal axis, showing how each variable changes as the CTD moves to the bottom and back to the surface.

Quadruple check on dissolved oxygen in Gulf waters the "old fashioned" way using a Winkler titration.

Triple check on dissolved oxygen in Gulf waters the “old fashioned” way using a Winkler titration.

 With storms in the path and not-so-plenty of fish in the sea, today is a slow day.

 

Personal Log

Looking out over the water, I can’t help but think how intrepid, even audacious, early mariners must have been. I know we are within a couple miles of the coast but there’s no sign of land anywhere in any direction. Even with the reassurance that satellites, radar, radios, AND trained NOAA Corps officers steering in the bridge are all keeping track of us, I still swallow a moment of panic. What kind of person decides to sail out in search of new continents when it only takes a couple hours to lose track of where you came from? And yet, the Polynesians set out thousands years ago in canoes from mainland Asia, the Aborigine ancestors managed to find Australia, and of course, Europeans sailed across the Atlantic to the Americas, whether they knew it or not. It was all possible through careful observations of the winds, waves, ocean currents, stars and other indications of direction, but I still have to think that that’s a pretty bold move when you don’t know if land lies ahead.

No land in sight.

No land in sight.

At least we’re not alone out here. These are some other animals that we’ll leave for the mammal survey and birders to count.

 

Did You Know?

The CTD also shows the layers of ocean water. Looking at the graph again for the red (salinity) and blue (temperature) lines, we can see where they cross at about 15 meters. This shows where colder, saltier water starts compared to the warm surface water that is diluted by fresh water and mixed by wind.

Lacee Sherman: Teacher Running Out of Witty Blog Titles June 27, 2018

NOAA Teacher at Sea

Lacee Sherman

Aboard NOAA Ship Oscar Dyson

June 6, 2018 – June 28, 2018

 

Mission: Eastern Bering Sea Pollock Acoustic Trawl Survey

Geographic Area of Cruise: Eastern Bering Sea

Date:  June 27, 2018

Snailfish!!!

TAS Lacee Sherman with an Okhotsk Snailfish

Weather Data from the Bridge at 15:00 on 6/27/18

Latitude: 56° 32.03 N

Longitude: 168° 08.15 W

Sea Wave Height: 2 ft

Wind Speed: 9 knots

Wind Direction: 229° (SW)

Visibility: 8 nautical miles

Air Temperature: 9.8° C

Water Temperature: 8.5° C

Sky:  Broken cloud cover

Water and cloud cover

Water and cloud cover on 6/27/18 @ 15:00

Science and Technology Log

Sometimes the pursuit of scientific knowledge requires very precise scientific instruments, and sometimes it just requires a bucket, funnel, and a coffee filter.  During the CTD casts, a special bottle collects water samples from a specific depth.  The CTD can hold multiple water sample bottles, so a few days ago I was able to choose the location for an extra water sample to be taken.  The required water sample was taken near the ocean floor, and I requested one at about 15 meters below the surface.

On the EK60 we had noticed a lot of “munge” in the water near the surface and we wanted to know exactly what was in the water that was reflecting an acoustic signal back up to the transducers since it did not appear to be fish.  The upper part of the water column that had the munge was expected to have more small and microscopic organisms than the sample taken at a lower depth because of what had been seen on the EK60.

Water Collection Bottle

CTD water collection bottles

The CTD water bottles have flaps on the ends that can be triggered at specific depths.  When the two CTD bottles were brought back on the ship, they were opened to pour out the water samples.  Once the required 1 liter sample from the bottle taken near the ocean floor was put aside for another scientific study, the rest of the water was put into large white buckets to be sampled and inspected as we saw fit.  We had one large bucket filled with water from near the bottom which we labeled “deep” and the water from only 15 meters down, which we labeled “shallow”.

We used coffee filters placed in funnels to strain out any microscopic organisms from the water.  We had one set up for the “shallow” water sample, and another for the “deep” water sample.  When there was a tiny bit of water left in the filter, we used a pipette to suck up the slurry of microscopic organisms and a bit of water and place them in a glass dish.  From there, we took a few drops from each dish and put them under a dissecting microscope.

Filtering Ocean Water

Funnel and coffee filter straining the living organisms out of ocean water

 

Using the dissecting microscope we were able to identify a few things that we were seeing, and even take photos of them through a special part of the microscope where a camera could be attached.  We did not individually identify everything that we saw, but we did notice that there were diatoms, rotifers, crab larvae, and some type of egg.  There was a noticeable difference though between the quantity of organisms in the shallow and deep samples.  As predicted, the shallow water sample had many more microscopic organisms than the deep water sample.

 

Personal Log

Yesterday we did two trawls and one Methot sample.  I understand so much more now about exactly how all of the instruments work and how to operate some of them.  I finally feel like I was getting the hang of everything and able to be more helpful.  Each trawl takes about 3 hours plus processing time, so the days pass much quicker when we are fishing often.

Methot net being brought on deck

Methot net coming on deck after a haul

In our second trawl of the day we ended  up catching a really neat kind of snailfish that isn’t very common.  It’s always exciting to get something other than pollock in the nets, and it was really neat this time since no one else had ever seen one before either!  After spending a lot of time taking photos, looking at identifying features and using books and the internet to help, we finally were able to identify it as an Okhotsk Snailfish.

Today we are steaming back to Dutch Harbor, AK and I have to admit that I have mixed feelings about leaving life on the ship behind.  I will miss being a part of research and working with the MACE team.  I love being able to do research, and work closely with scientists and learn more about something that I really enjoy.  I will also definitely miss seeing the ocean every day.  I think it will probably be strange to walk on land now.  Since the ground won’t be moving anymore, hopefully that means that I can stop walking into walls!

All operations stopped on the ship last night so that we can have enough time to make it back to land before 09:00 on June 28, 2018.  Today I will be packing up my things, cleaning up my room for the next person, and then helping to clean and scrub the fish lab. Tomorrow I will return to life as a land dweller, although hopefully not forever.

Did You Know?

According to the Encyclopaedia Britannica, “The Bering Sea has more than 300 species of fish, including 50 deep-sea species, of which 25 are caught commercially. The most important among them are salmon, herring, cod, flounder, halibut, and pollock.”

 

 

 

Kimberly Godfrey: Night time..Day time! June 10, 2018

NOAA Teacher at Sea

Kimberly Godfrey

Aboard NOAA Ship Reuben Lasker

May 31 – June 11, 2018

 

Mission: Rockfish recruitment and ecosystem assessment survey

Geographic Range: California Coast

Date: June 10, 2018

Data from the Bridge

Latitude: 36° 39.980′ N

Longitude: 122° 33.640′ W

Wind: 30.87 Knots from the SE

Air Temperature: 12° C

Waves: 2-3 feet with 6-8 foot swells

Science Log

As you may have gathered from my previous blogs, I spent my time working with the night scientists. However, there was a lot happening during the daylight hours that I would like to highlight. There was a separate team assigned to the day shift. Some of their tasks included analyzing water samples, fishing, and surveying marine mammals and seabirds.

Catching fish during the day allowed them to see what prey were available to diurnal predators, and they could also compare their daytime catch to the evening catches. They used a different net called a MIK Net, which is a smaller net used for catching smaller and younger fish.

MIK Net

The MIK net used by the day time scientists to catch juvenile fish.

The day shift is also the best time for spotting seabirds and marine mammals. Some of the bird species spotted included brown pelican, common murre, terns, black-footed albatross, shearwaters, and at least 1 brown booby. The marine mammals we spotted included humpback whales, fin whales, blue whales, common dolphins, and sea lions.

I had an opportunity to speak with Whitney Friedman, a postdoctoral researcher with NOAA, and she explained to me some of the goals of their marine mammal survey. Many may recall that there was a time when whale populations, especially humpback whales, were in significant decline. Today, humpback whales are considered a success story because of rebounded populations. The concern now is monitoring the success of their food sources. Humpback whales feed on krill and fish like anchovies. However, it is possible that when these sources are less available or as competition increases, they may feed on something else. The question is, what is that something else? During this survey, one goal was to collect whale scat for analysis. Studies have found that some seabirds feed on juvenile salmon incidentally when their preferred local prey is limited, and they move inshore to feed on anchovy. Is it possible that whales might do the same? What else might they be foraging on? Unfortunately, we did not have much luck catching whale scat this time around, but they will try again in the future, and hopefully will find the answers they are looking for.

As previously mentioned, we also did water quality tests and took water samples using the Conductivity, Temperature, and Depth (CTD) Rosette. This instrument has multiple functions. As the initials suggest, it detects conductivity (the measure of how well a solution conducts electricity) and temperature at any given depth. Salinity (the amount of dissolved salts and other minerals) and conductivity are directly related. By knowing the salinity and temperature, one can determine the density. Density is one of the key factors that drives the ocean currents. Many species depend on the ocean currents to bring in nutrients and food. It all comes full circle.

CTD

CTD Rosette used to capture conductivity, temperature, and depth. We also used this to take water samples at specified depths.

CTD

The CTD is lowered into the water by a winch with the assistance of the deck crew.

When we lowered the CTD we could also take water samples at any given depth. This allowed scientist to test for various parameters. For example, we filtered various water samples to determine the amount of chlorophyll at certain depths. This can help scientists estimate the growth rates of algae, which in the open ocean are called phytoplankton. One of the scientists collected water to analyze for environmental DNA (eDNA). This is DNA that might be left in the air, soil, or water from feces, mucus, or even shed skin of an organism. In her case, she was trying to find a way to analyze the water samples for sea turtle DNA.

I’ve heard of eDNA, but I have never actually understood how they collected and analyzed samples for this information. My understanding is that it can be used to detect at least the presence of an extant species. However, when collecting these samples, it is likely to find more than one species. Scientists can use previously determined DNA libraries to compare to the DNA found in their samples.

Personal Log

We started trawling again on the evening of June 7th. By then we settled ourselves into the protection of the Monterey Bay due to the weather getting bad. While we still had some off-shore stations, we tried our best to stay close to the bay because of the wind and swells. We had some interesting and challenging trawls in this area: lots of jellyfish. Some of the trawls were so full we had to actually drop the catch and abort the trawl. If not, we risked tearing the net. We tried to mitigate the overwhelming presence of jellies by reducing our trawls to 5 minutes instead of 15 minutes, and we still had similar results. One night, we had to cancel the final trawl to sew up the net. I’ve been told that sewing a fish net is an art form. Our deck hands and lead fisherman knew exactly what to do.

Let me tell you my experience with jellyfish during the survey. As you may recall, someone must be on watch for marine mammals on the bridge. This is the ship’s control room that sits on the 5th level above water.

Reuben Lasker

The Bridge of the Reuben Lasker is where we do inside Marine Mammal Watch. This is where the main controls of the ship are located.

From here you can see the surface of the water quite well, which makes it a great spot for the marine mammal watch. It was also great for watching hundreds of moon jellies and sea nettles float right by. It was one of the coolest things to watch. It was somewhat peaceful, especially hanging your head out of the window, the cool air blowing against your face, and the occasional mist of sea spray as the ship’s hull crashes against some of the larger swells. However, that same peaceful state disappears the moment you realize, “I’m gonna have to lift, count, and sort all those jellies!” I wasn’t too concerned about being stung; we had gloves for the sea nettles and the moon jellies were no real threat. However, the sea nettles (Chrysaora fuscenscens) smelled AWFUL, and the moon jellies (Aurelia spp.) are quite large and heavy. I’m honestly not sure how much they weighed; we did measure up to 20 per haul, some of them measuring over 400 mm. Even if they weighed about 5 pounds, lifting 50-60 of them consecutively until the count is complete is enough to get the muscles burning and the heart rate elevated. It was a workout to say the least. I was literally elbows deep in jellyfish. I also wore my hair in a ponytail most of the time. Anyone that knows me knows well enough that my hair is long, and definitely spent some time dipping into the gelatinous goop. I smelled so bad! HAHAHAHA! Nonetheless, it was still one of the most intriguing experiences I’ve had. Even though the jelly hauls proved to be hard work, I enjoyed it.

In those last few days, I felt like I became integrated into the team of scientists, and I felt comfortable with living out at sea. I had a few moments of nausea, but never really got sea sick. I still couldn’t walk straight when the ship rocked, but even the experts wobbled when the ship hit the big swells. Then, that was it for me. By the time I got the hang of it all, it was time to leave. I wish there were more hours in the day, so I could have experienced more of the day time activities, but I still got to see more than I thought I would, and for that I am grateful.

Did you know…

NOAA offers many career options. As a scientist, here are some things one might study:

  • track and forecast severe storms like hurricanes and tornadoes; monitor global weather and climatic patterns
  • Research coastal ecosystems to determine their health, to monitor fish populations, and to create policies that promote sustainable fisheries
  • Charting coastal regions and gathering navigational data to protect the ship from entering unsafe waters

NOAA Corps allows one to serve as a uniformed officer, commanding a ship or piloting aircraft. On NOAA Ships, they need engineers, technicians, IT specialists, deck hands, fishermen, and even cooks (The Reuben Lasker had two of the best, Kathy (Chief Steward) and Susan (second cook)). There are many opportunities available through NOAA, and there is a longer list of amazing experiences one can have working for this organization. If you want to explore in more detail, visit http://www.careers.noaa.gov/index.html

 

Heather O’Connell: Soil Samples, Surveying and Sumdum Glacier, June 17, 2018

NOAA Teacher at Sea

Heather O’Connell

NOAA Ship Rainier

June 7 – 21, 2018

Mission: Hydrographic Survey

Geographic Area of Cruise: Seattle, Washington to Sitka, Alaska

Date: 6/17/18

Weather Data from the Bridge

Latitude and Longitude: 57°43.2’ N, 133 °35.7’ W, Sky Condition: Overcast , Visibility: 10+ nautical miles, Wind Speed: 2 knots, Sea Level Pressure: 1024.34 millibars, Sea Water Temperature: 7.2°C, Air Temperature: Dry bulb: 11.78°C, Wet bulb: 10.78°C

Science and Technology Log

I was part of the crew launched on RA-3 where I learned to turn towards a man overboard in order to ensure that the stern of the ship turns away from them. Communicating via the radio was another highlight where I was certain to follow the proper protocol.

RA- 3 Launch with Multi-beam sonar

RA- 3 Launch with Multi-beam sonar

Next, we moved onto deploying the C.T.D., conductivity, temperature and depth device to determine the sound profile of the water. The winch is a pulley system off the back of the launches that casts the C.T.D. and functions similar to a crab pot winch with an addition of a pressure bar to alleviate the weight of the thirty pound C.T.D.

Deploying the C.T.D.

Able Bodied Seaman Tyler Medley and Junior Officer Michelle Levano deploying the C.T.D.

After passing an iceberg with a seal, we began collecting soil samples with a device called a grab sampler. This was connected to the winch and went down about three hundred and thirty feet to collect a bottom sample. The first sample consisted of small shells of mostly barnacles, along with some medium grained sand and large silt submerged in solution.  The second sample was pristine clay with a slight green color created from the physical erosion of the surrounding rocks of the mountains. Soil sample data is collected and included in the data report because it can affect the sound speed of water. It can also provide useful information about the types of organisms that could live in this ecosystem, along with the types of resources available in this area.

Grab Sampler

Grab Sampler

Next, we connected with RA-6 and had a crew transfer so that I could learn how hydrographic surveying actually works. Newly certified H.I.C., hydrographer in charge, Audrey Jerauld was kind enough to share her knowledge of conducting surveying within Tracy’s Arm. Since Rainier surveyed most of the channel, RA-6 was simply collecting near shore data using the multi-beam sonar. The I.M.U., inertial measuring unit, (not to be confused with the Hawaiian imu which is an underground cooking pit) accurately records the pitch, roll, heave and yaw of the boat. This allows GPS receivers to function even when a satellite is not available. I learned that this is important since when surveying next to a steep cliff,when the satellite cannot reach the small launch, this provides an alternate, accurate means of placement. It determines a D.R., or dead reckoning based on the I.M.U. accelerators and creates a plot of where it thinks the launch is. 

deploying C.T.D.

Junior Officer ENS Collin Walker and H.S.T Audrey Jerauld deploying C.T.D.

Personal Log

The sun was shining yesterday afternoon and I loved soaking up the Vitamin D offered by the sun’s rays while practicing yoga on the flying bridge. When Junior Officer Ian Robbins invited me to go kayaking, I eagerly accepted the opportunity to explore Holkham Bay on a kayak with more maneuverability. I descended into the kayak via a rope ladder off the ship and paddled about three miles through a kelp forest to the nearby Sandy Island. Here, there were endless barnacles, urchins, starfish and kelp to explore near the shore in this inter tidal ecosystem. After pulling the kayaks up to shore and exploring land, I had the realization that with each step I was crushing more living organisms than I cared to consider. The rocks and shells soon turned to rye grass and marshland with some larger rocks.

Sunflower Star

Sunflower Star, Photo Credit: Ian Robbins

Seastar in Intertidal Zone

Seastar in Intertidal Zone

We eventually pulled the kayaks to the other side of the island and kayaked our way next to a blue iceberg. Seeing concentric circles and the intricate pattern of the frozen water crystals was a spectacular sight. Kayaking around such a beautiful natural phenomenon that has been in existence much before I have, was again, a humbling experience.

Iceberg off Sandy Island

Iceberg off Sandy Island

Paddling back to the ship with Sumdum glacier to the right and passing through a narrow channel that lead to the beautiful golden glow of the sun about to set proved to be a perfect ending to an exciting day. Feeling amazed at the sight in every direction made me once again feel extreme gratitude for this exceptional opportunity to be around such vast beauty.

Holkham Bay Sunset

Holkham Bay Sunset

Did You Know?

Mooring line, or the rope used to tie a ship to the dock, is often made of spectra. This synthetic polymer, spectra, doesn’t stretch and is extremely strong, so much so that it can bend metal if enough tension is put on it. It is three times stronger than polyester.

Heather O’Connell: Sound in Seawater and Sleeping at Sea, June 8, 2018

NOAA Teacher at Sea

Heather O’Connell

NOAA Ship Rainier

June 7 – 21

Mission: Hydrographic Survey

Geographic Area of Cruise: Seattle, Washington to Southeast, Alaska

Date: 6/8/18

Weather Data from the Bridge: Latitude: 48.15° N, Longitude: 122 ° South 58.0’  West, Visibility: 8 nautical miles, Wind: 24 knots, Temperature: 14.2° C

Science and Technology Log

I was fortunate enough to sit in on a survey orientation for new survey technicians and junior officers with Lieutenant Steven Loy. He was on Rainier as the Field Operations Officer, F.O.O., in the past and is currently here as an augmenter filling the role of Senior Watch Officer since he has navigated through the Inside Passage several times. In his two hour orientation, he shared a wealth of knowledge and discussed how multibeam sonar and ultrasounds are two opposite ends to the ultrasonic pulse spectrum.

Multibeam sonar sends out sound and measures the time it takes to return to calculate the depth of the ocean floor. The accuracy of the depth data generated from the multibeam sonar relies on the sound speed profile of the water. The combined effects of temperature, salinity and pressure generate a sound speed profile. Because of the inherent importance of this profile, there are several different ways to measure it. The sound velocity profiler measures this right at the interface of the multibeam sonar. C.T.D.s., or conductivity temperature and depth machines, measure water profile while the ship is stopped. M.V.P.s, or moving vessel profilers, take the water profile as the vessel is moving. Lastly, XBTs are expendable bathythermographs that measure temperature while the ship is in motion.

Sound is affected by different variables as it is energy that travels through a medium as a wave. Lieutenant Loy shared an informative website, The Discovery of Sound in the Sea, where I was able to enhance my understanding. Sound can travel through a liquid, such as water, a gas like air, or a solid like the sea floor. On average, sound travels about 1500 meters per second in sea water. However, the rate changes at different times of day, various locations, changing seasons and varying depths of the water. By looking at sound speed at one particular place in the ocean, you can determine how the different variables affect this sound. Usually, as depth increases, temperature decreases, while salinity and pressure increase.

A multi-beam sensor has a metal plate receiver and a transmitter perpendicular to one another. This array geometry enhances sound.  The sound velocity profiler is next to the receiver and measures right at the interface. To determine the speed of sound right where the beam is generated, sonar is used to measure speed sound across a known distance. This information is then utilized in the overall determination of the depth of the ocean floor. Once this cast is taken, the Seafloor Information System (SIS), can adjust sonar measurements accordingly.

Another way to measure the sound profile of water includes a C.T. D.  This device measures the conductivity, temperature and depth of the water. Conductivity measures the electrical current of the water. The more dissolved salt, or ions in solution, the greater the conductivity and salinity of the water. The depth of the water is directly related to the pressure of the water. Salinity, temperature and pressure affect the sound speed profile of water. This machine has a high data rate that goes up and down the water column. The titanium C.T.D. operates at a high pressure and costs about forty thousand dollars. This accurate technology can only be utilized when the boat is stopped and is used on the smaller survey launches.

C.T.D. used for sound speed profile of water

C.T.D. used for sound speed profile of water

A third method of measuring sound profile is the M.V.P., moving vessel profiler, which takes the data when the ship is moving. These are calibrated before a survey begins and are an efficient way to collect data. An expansive crane lowers the metal torpedo with the sensor off the fantail, the overhanging back part of the ship, into the water to collect the data. The fish is programmed to stop twenty meters above the ocean floor, at which point it returns to its docked position. On ship Rainier, the deck department deploys the fish with a cable wire and the plot room with the survey technicians controls the sensor.  

Boatswain Kinyon and Survey Technicians Finn and Stedman releasing the torpedo of the M.V.P. into the water

Boatswain Kinyon and Survey Technicians Finn and Stedman releasing the torpedo of the M.V.P. into the water

Another way to collect the sound profile of water with a moving vessel is to use an expendable probe. As temperature decreases, the sound speed decreases. Since temperature is the most important factor affecting the speed of sound, an X.B.T., Expendable Bathythermograph, or expendable probe created by the military. With bathy relating to depth and thermo meaning heat, this measures the temperature of the water at a cost of about one hundred dollars. These probes descend at a known rate, so, depth is a function of time.

Sources – Discovery of Sound in the Sea

Personal Log

We left port yesterday at 16:30, which has been a highlight of my NOAA Teacher at Sea Experience thus far. Before leaving port, all hands were assigned a different assignment to help with the launch. I watched the crew bring in the gangway that connects the ship to the port then disassemble it. The crew with hard hats and orange work vests took down poles and neatly tied up different sections by knotting ropes. We slowly progressed out of the port after a cargo ship passed us.  

The deck crew preparing to leave port

The deck crew preparing to leave port

Once the ship picked up speed and the ocean breeze was in my hair, I felt a new kind of freedom. With the Seattle skyline behind us and the beautiful green peninsulas in front of us, I was content to be moving forward. Everyone seemed to feel relieved once we were underway. I felt gratitude as I enjoyed watching the sunset from the flying bridge, the area of the ship above the bridge at the front of the ship.

Seattle Skyline

Seattle Skyline

After sunset, I returned to my berth, or sleeping quarters, located in the bow of the ship on the C-deck. I heard the constant white noise of the propellers that got much louder when the pitch, or angle, of them changed. This sound of seawater combined with the rocking motion of the ship lulled me to sleep on our first night at sea.

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Sunset

Did You Know?

Juneau, the American capital of Alaska, can only be entered by plane or boat. It is inaccessible by roads due to large mountain ranges on either side.

Susan Dee: To the Gulf of Maine and Georges Bank, June 1, 2018

 

NOAA Teacher at Sea

Susan Dee

Aboard NOAA Ship Henry B. Bigelow 

May 23 – June 7, 2018

Mission:  Spring Ecosystem Monitoring Survey

Geographic Area of Cruise: Northeastern Coast of U.S.

Date:  June 1,  2018

Weather From Bridge

Latitude: 41° 25.4′ N
Longitude: 068° 16.3′ W
Sea Wave Height: 1-2 ft
Wind Speed: 16 kts
Wind Direction: SE
Visibility: Hz
Air Temperature:  12.5°C
Sky:  OVC

Science and Technology Log

After completing a southern route past Long Island, New Jersey and Delaware, the Henry B. Bigelow  headed north to the Gulf of Maine (GOM).  The first sampling stations in GOM were  located on the continental shelf close to the slope. After sampling in  the  Northeast Channel of the GOM, stations will be dispersed throughout the Gulf of Maine. Phytoplankton is continuously imaged through the Imaging Flow Cyto Bot and collection is going well. Below is a recent image taken.  Can you  find Thallasonemia  or Ceratium?  

phytoplankton 3

Image of Phytoplankton taken by IFCB

At various stations instead of  towing  bongo nets  with a CTD attached,  a CTD, Rosette, is deployed with niskin bottles.  CTD contain sensors that measure Conductivity (salinity), Temperature and Depth.   The data gathered provides profiles of chemical and physical parameters of the ocean.

CTD with 12 canisters on deck

CTD on bottom of instrument with 12 Niskin bottles forming a rosette.

 

CTD Rosette entering-water.jpg

CTD, commonly known as Rosette. Note the rosette shape at top of bottles

The great feature of the rosette is its ability to collect water using Niskin bottles as hydrographic instruments.  Opened bottles are lowered into the ocean and at the desired depth a   bottle is closed and brought to the surface without mixing with other water so pure samples can be taken at different depths. Back on board, water is  taken from the Niskin bottles and  nutrient, chlorophyll and carbon dioxide tests are run on the samples.

taking water samples susan

Susan taking water samples from niskin bottles to perform chlorophyll tests at 3 different depths.

chlorophyll extraction

Chlorophyll extraction set up

Georges Bank is  in the southern part of the Gulf of Maine.  The bank separates the Gulf of Maine from the Atlantic Ocean.  It is a huge shoal that is 100 meters higher  than the surrounding ocean floor and is a very productive area of the continental shelf.   The mingling of the Labrador current from the north and the Gulf stream on the eastern edge plus sunlight in shallow waters, creates an ideal environment for phytoplankton and zooplankton. Once a bountiful fishery, it is presently recovering from over fishing. Federal Fishery regulations aim to ensure recovery of the area and future sustainability. The data samples collected will give a good idea of the recovery of this area.    The pink line below shows  the route taken by our ship in the southern Gulf  of Maine and  Georges Bank.

IMG_2518

When  we were near the Northeast  Channel  in the Gulf of Maine, Latitude 41° 53.2′ N and Longitude 65°47.0′ W,  I deployed a  satellite-tracked Drifter Buoy decorated with our school name May River Sharks.  The drifter buoy will send GPS and temperature data to a NOAA website and students will be able to track its path.  This area was chosen to deploy because the Labrador current   from the north meets with the Gulf Stream and hopefully the buoy will get caught up in one of the currents. It will be fun  for students to track the buoy path in the fall. Wonder where it will go???

 

Susan&Buoy

Susan decorating Buoy- May River High School Sharks

 

 

Buoy 1

Buoy READY

 

Buoy Released

Buoy Released

 

DCIM100GOPROG0021640.

Buoy splashing into water

buoy floating

Oh where, oh where, will you go?

 

Personal Log:

So far this trip the weather has been great. Seas have been calm and temperatures good. I have fallen into a nice routine each day.  My shift concludes at midnight; I go to bed till 9:00AM; work out; shower and get ready for next 12 hour shift. I eat lunch and dinner each day and a midnight snack.  The days are long but never boring. The crew aboard the Henry B Bigelow  is awesome.  Internet is sporadic but  I was able to face-time with my daughter. Technology is a big part of this whole operation. All the programs collecting temperature, salinity and phytoplankton rely on computer programs to run. Second  to the chef, the IT person is invaluable.  They are trouble shooting problems all day to make sure the collection  of data is working.   During the longer steams from station to station, I  have the opportunity to talk to crew and other scientists.  Each person is excited about science.  I have never  been involved in real  science research and I  find each day to be fascinating. There is so much time and effort put into collecting the samples.  This cruise  will collect samples from over 100 stations that will be analyzed and supply much data to give a good picture of the state of our Northeast coastline waters and fisheries.

Today was the last day of school for the year for May River High School.  Graduation is Tuesday and my thoughts will be with everyone.  Congratulations to all my students, especially the seniors.

Answers to Phytoplankton Identification:

Thallasonemia- upper left corner

Ceratium- middle top