Tag: chlorophyll

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Karen Matsumoto, April 25, 2010

NOAA Teacher at Sea: Karen Matsumoto
Onboard NOAA Ship Oscar Elton Sette
April 19 – May 4, 2010

NOAA Ship: Oscar Elton Sette
Mission: Transit/Acoustic Cetacean Survey
Geographical Area: North Pacific Ocean; transit from Guam to Oahu, Hawaii, including Wake Is.
Date: Friday, April 25, 2010

Science and Technology Log

The Oscar Elton Sette is making its way to Wake Island, and we hope to be there by tonight. One of the research operations is to recover a HARP (High-frequency Acoustic Recording Package) that is in place on Wake Island and replace it with a new HARP unit.

This morning, I was on “CTD duty” at 4:30 a.m. A CTD (conductivity-temperature-depth) station is deployed prior to the start of the visual survey effort, right at sunrise. The CTD data is collected using the ship’s SeaBird CTD shown below. The CTD is deployed to a depth of 1000 meters (depending on depth where we are) with a descent rate of about 30 meters per minute for the first 100 meters of the cast, then at 60 meters per minute after that. It takes three people, plus a winch driver to deploy the CTD, as well as the expert operation from the bridge to keep the ship steady and in one place during the entire operation!

Checking the CTD unit prior to launch.
Launching the CTD unit.
Background on CTDs

The CTD is a device that can reach 1,000 meters or more in depth, taking up to five water samples at different depths, and making other measurements on a continuous basis during its descent and ascent. Temperature and pressure are measured directly. Salinity is measured indirectly by measuring the conductivity of water to electricity.

Chlorophyll, a green photosynthetic pigment, is measured indirectly by a fluorometer that emits purple light and measures fluorescence in response to that light. These measurements are made continuously, providing a profile of temperature, salinity, and chlorophyll as a function of depth. The CTD unit is torpedo-shaped and is part of a larger metal water sampling array known as a rosette. Multiple water sampling bottles are often attached to the rosette to collect water at different depths. Information is sent back to the ship along a wire while the instrument is lowered to the depth specified by the scientist and then brought back to the surface.

Monitoring the CTD in the ship’s E-lab.
Data gathered from the CTD during its descent.

By analyzing information about the water’s physical parameters, scientists can make inferences about the occurrence of certain biological processes, such as the growth of algae. Knowledge like this can, in turn, lead scientists to a better understanding of such factors as species distribution and abundance in particular areas of the ocean.

I am continuing my acoustic work with the sonobuoys. Today I heard a Minke whale BOING! Below is what a Minke whale boing looks like on the computer. It sounds very much like someone blowing a low tonal whistle or a cell phone vibrating on the desk!

 

To hear an Atlantic minke whale call (which is different from those found here in the North Pacific, but really cool!) go to this website:

http://www.pmel.noaa.gov/vents/acoustics/whales/sounds/sounds_atlminke.html

Personal Log

I am making so many great friends among the Sette crew and the science team! I am getting spoiled from all the fantastic meals put together by Randy our cook, and no one ever wants to miss a meal! Our wonderful Doc Tran makes incredible Vietnamese dishes and delicious desserts. Today we had cream puffs for dinnertime dessert! Who would have ever guessed!

Marie Hill, our Chief Scientist and fearless leader was awarded the prestigious NOAA Team Member Award! We surprised her with balloons and decorations in her cabin, and Doc Tran and Lisa made a yummy cake in celebration! Congratulations Marie!!!

Marie Hill, Chief Scientist finding her cabin wildly decorated to congratulate her on her award.

We had a visitor today on the flying bridge-an exhausted juvenile red-footed booby! He sat on the mast, finding a place to rest in the middle of the ocean! It felt great to feel the warm wind hit my face and watch the sapphire blue water crash against the bow of the ship! What a great feeling!

Juvenile red-footed booby on the bridge
Deep blue Pacific ocean water!

Question of the Day: How can you figure out how much food to bring on a 2-week cruise? How do you keep the food fresh? What do you do with leftovers?

This is the situation that the Chief steward has to deal with on every cruise! How would you figure this out? Can you do the math?

New Term/Phrase/Word of the Day: Beaufort Sea State is an empirical measure for describing wind speed based mainly on observed sea conditions. It is also called the Beaufort Wind Force Scale. We stop conducting our visual observations when wind/sea conditions reach Beaufort 7, as wind and sea conditions are too rough to accurately make observations (and its windy out there!).

Something to Think About:

This part of the North Pacific is often described as an ocean desert. We have not seen any whales, and have had only a couple sightings of dolphins since we left Guam. We have also seen migrating sea birds, but not in huge numbers. What do you think may account for the lack of sea life in this expanse of tropical waters?

Animals Seen Today:

  • Sooty tern
  • Red-footed booby (juvenile)

Did you know?

That the team of whale visual observers never discuss the numbers of animals they see among themselves. Some people consistently count high, others count low, others are spot on! By not discussing how many animals they observed, they don’t influence each others’ observations. Back at the lab, researchers compare each observer’s counts from their written observations, and can tell which observers tend to under or overestimate numbers of animals they see. They can then make adjustments to total numbers based on everyone’s observations! This is similar to calibrating thermometers or other scientific equipment!

Today’s sunset from the Sette.
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Mary Anne Pella-Donnelly, September 11, 2008

NOAA Teacher at Sea
Mary Anne Pella-Donnelly
Onboard NOAA Ship David Jordan Starr
September 8-22, 2008

Mission: Leatherback Use of Temperate Habitats (LUTH) Survey
Geographical Area: Pacific Ocean –San Francisco to San Diego
Date: September 11, 2008

CTD deployment
CTD deployment

Weather Data from the Bridge 
Latitude: 3647.6130 W Longitude: 12353.1622 N
Wind Direction: 56 (compass reading) NE
Wind Speed: 25.7 knots
Surface Temperature: 15.295

Science and Technology Log 

One important piece of equipment on many NOAA research ships is the CTD (Conductivity and Temperature with Depth).  This eight chambered water collection device is attached to electronic sensors. When the CTD is deployed below the ocean’s surface, it is dropped carefully to a predetermined depth; today’s was 500 m. All water collection chambers are open for water to flow through. After the oceanographer in charge of deployment examines a computer readout of the CTD after it has been lowered to its’ maximum depth, it is decided at which depths water samples will be collected as the CTD is brought back up.At these intervals, water sample collectors (Niskin bottles) are closed and water collected.  Up to eight samples are collected as it rises to the surface.

CTD reading; salinity, oxygen, pressure, and fluorometer voltage
CTD reading: salinity, oxygen, pressure, and voltage

After the CTD has been secured on deck, each sample is carefully extracted into collection bottles. Each water sample is filtered through a vacuum system in order to extract chlorophyll from that water sample.  The extracted chlorophyll is later run through a fluorometer, which calculates the volume of chlorophyll a and chlorophyll b which indicates the intensity of photosynthetic microorganisms in that layer. Lots of chlorophyll indicates a rich biological region, which may support many types of marine life.  In addition, the CTD collects samples that will be analyzed for the amount of salts they contain in order to confirm the sensors values. Values that change to the left are decreasing. The reading on the top right shows how the temperature, in red, changes very quickly from the surface down to 500 m.  The green indicates some chlorophyll until it drops significantly below 100 m, where light no longer penetrates well. Oxygen levels are in blue, also decreasing with depth.

Questions of the Day 

  1. What is the importance of chlorophyll to marine mammals and amphibians?
  2. Why is an understanding of how pressure and depth below the ocean’s surface are related critical to marine sciences?
Water samples being filtered through a vacuum system to extract chlorophyll.
Water samples being filtered through a vacuum system to extract chlorophyll.

 

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Jillian Worssam, July 24, 2008

NOAA Teacher at Sea
Jillian Worssam
Onboard U.S. Coast Guard Vessel Healy
July 1 – 30, 2008

While looking at the collected sediment trap, it is obvious that many unsuspecting pieces of debris were caught within its clutches.
While looking at the collected sediment trap, it is obvious that many unsuspecting pieces of debris were caught within its clutches.

Mission: Bering Sea Ecosystem Survey
Geographic Region: Bering Sea, Alaska
Date: July 24, 2008

One of the pleasures while at sea is the concept of time; which is in a word, timeless. Last night the sun set around three in the morning, and if you had asked me what day it was when I went to bed, I could not have answered. I know the date because I made files prior to this cruise so that I could keep track, in some infinitesimal way, of my journals. Right now I know for sure that I am a day behind in writing, that the cruise will be over in less than a week, I still have a lot more science to learn and this afternoon I am making Apple Crisp for the Morale dinner. These things I know, what I am still learning is the science of a sediment trap.Pat Kelly is from the University of Rhode Island Graduate School of Oceanography, and he is here, in part, to collect sediment samples that float in the ocean.

There are many components to the research Pat is working on; one is in collecting particles sinking vertically in the ocean. By using an established brine (denser NaCl) solution in an array of floating tubes Pat is able to catch these falling sediments. The process is to deploy his trap, a series of tubes for the falling sediments held aloft by floats that drift in the ocean, for no more than 24 hours.

After the brine from the sediment trap is filtered and dried the collected sediments will be analyzed.
After the brine from the sediment trap is filtered and dried the collected sediments will be analyzed.

When collected, Pat will remove the sediments from the brine, looking at the thorium and organic carbon, there is a relationship between these two elements and Pat wants to focus particularly on the carbon. Now this is where it gets sticky for me as I am not a chemical oceanographer. Pat is looking at the carbon flux. The team wants to look at the carbon transfer as it changes from atmospheric carbon, to organic carbon in the oceans, thus taking it out of the carbon cycle.

The scientists making sure the trap is ready before being deployed off the back deck of the vessel.
The scientists making sure the trap is ready before being deployed off the back deck of the vessel.

One of the underlying questions in this component of the HEALY research is how the oceans will respond to all the increased carbon due to global climate change. Pat’s group is actually looking at carbon cycling in many different oceans, with their hypothesis: The arctic will respond faster to increases in carbon (changes more apparent, faster), due to decreased ice, and the fact that it is dark for ½ the year. Think of it this way, after a long dark winter with good nutrient build up, a higher yield is to be expected with 24 hours of sunlight. The sinking particles Pat studies are also very important to the benthos species providing nutrients and food as they sink.

The scientists are carefully retrieving the tubes of brine that for the past 24 hours have collected ocean sediments.
The scientists are carefully retrieving the tubes of brine that for the past 24 hours have collected ocean sediments.

Like many of the scientists on board, Pat is doing multiple investigations. The ocean as I talked about before is layered and Pat’s team is looking at productivity in the mixed layer using 02 isotopes. This data will give the scientists the rate that phytoplankton is growing.

The team also uses radium isotopes to estimate advection of deep water to the surface along the shelf break. The information will tie in with the scientists studying iron. There is belief that the iron is up welled from the sediments in the deep water to the surface layers.

I am still learning about the chemistry of ocean science, and do not fully understand all of Pat’s research. I do though see that everything is intimately linked, that all components of this ecosystem are dependent upon each other and if one component is changed then ALL will change as well.

I hope to never be so jaded as to not appreciate the beauty in nature.
I hope to never be so jaded as to not appreciate the beauty in nature.

Quote of the Day: Come forth into the light of things, let nature be your teacher. -William Wordsworth

FOR MY STUDENTS: No question for today, go out and enjoy the sunset!

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Jillian Worssam, July 23, 2008

NOAA Teacher at Sea
Jillian Worssam
Onboard U.S. Coast Guard Vessel Healy
July 1 – 30, 2008

Mission: Bering Sea Ecosystem Survey
Geographic Region: Bering Sea, Alaska
Date: July 23, 2008

Last night I went to bed at four, my wake up call was for seven forty five this morning, needless to say if I have a little difficulty explaining micro-zooplankton there is an excuse.Today I am spending time with Diane Stoeker and Kristen Blattner, both from The University of Maryland Center for Environmental Science.

If she is not at the computer Diane is either at the microscope, the incubators or working on her phytoplankton experiments.
If she is not at the computer Diane is either at the microscope, the incubators or working on her phytoplankton experiments.

Diane and Kristen are studying phytoplankton and micro-zooplankton, and it is amazing how these small components of an oceanic ecosystem are vital for the survival of pretty much the entire environment. Diatoms are small single-celled organisms, called phytoplankton. Diane is studying how fast phytoplankton are eaten by micro zooplankton, and how this “grazing” effects phytoplankton populations.

It is a long process to measure water and extract chlorophyll, Kristen is up for the challenge.
It is a long process to measure water and extract chlorophyll, Kristen is up for the challenge.

Let’s try a visual

Phytoplankton = the microscopic “plants” of the ocean. These organisms photosynthesize and drift with the current. Although some phytoplankton do have locomotive capabilities they cannot swim again the current.

Diatoms are a type of phytoplankton. Zooplankton = small animals who also move with currents and eat phytoplankton as well as micro-zooplankton.

Now enter Diane and Kristen, they look at phytoplankton to find out what is eating them, predominantly micro-zooplankton, and are even looking at their relationship with zooplankton pee and how it might work as a fertilizer for phytoplankton. What these ladies do is collect samples of sea water once a day. They use a mixture of 20% whole sea water and 80% filtered sea water (which removes most of the algae, copepods and protozoa), and a 100% whole sea water sample.

This is part of the larval stage, nauplius of a copepod.
This is part of the larval stage, nauplius of a copepod.

Kristin then strains both types of water pre and post incubation, and will compare the chlorophyll samples. What Kristin is hoping for is that after 24 hours there will be more chlorophyll in the 20/80 sample indicating greater phytoplankton growth, due in part, to the fact that there are fewer predators (micro-zooplankton) in this water. Micro-zooplankton eat nearly 50-60% of the phytoplankton, which they are fertilizing at the same time. This relationship is fundamental to a healthy oceanic ecosystem; you could even say these micro-zooplankton help sustain the growth if phytoplankton in the ocean.

After the 24 hour incubation, samples are taken for further study back at the lab. One specimen they often see is a heterotrophic dinoflagellate. This guy has no chlorophyll and wants to eat phytoplankton; it is in other words a micro-zooplankton.

This little gem does not photosynthesize and locomotors by the little hair like tenacles.
This little gem does not photosynthesize and locomotors by the little hair like tenacles.

As I look at the pictures Diane has taken, I am transported to a word that is so small that to tell the difference between plant is animal is very difficult.

Isn't this a great looking microzooplankton, can you see how it moves?
Isn’t this a great looking microzooplankton, can you see how it moves?

Quote of the Day: The great sea has sent me adrift, it moves me, it moves me, as the weed in a great river. Earth and the great weather move me, have carried me away and moved my inward parts with joy. Uvavnuk Eskimo Song

FOR MY STUDENTS: What other areas of study can we focus on while using microscopes?

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Karolyn Braun, October 18, 2006

NOAA Teacher at Sea
Karolyn Braun
Onboard NOAA Ship Ka’imimoana
October 4 – 28, 2006

Mission: TAO Buoy Array Maintenance
Geographical Area: Hawaii
Date: October 18, 2006

TAS Braun using the Fluorometer to test CTD water samples.
TAS Braun using the Fluorometer to test CTD water samples.

Plan of the Day 

Transit; TAO buoy painting; Testing CTD samples using the Fluorometer

Woke up at 5am to get a head start on the painting. I’d rather work in the morning before the sun comes up.  I finished painting the white strips before breakfast so the crew could flip the buoys over to paint the red on the bottoms before the end of the day. I spent most of my day in front of the Fluorometer testing the CTD water samples.

Ok Learning time: To calculate chlorophyll you need to use the following equation: Chl (ug 1 ) = F*Ve((Fo-Fa)/S)Vf Where F = fluorometer calibration factor

Fo = total fluorescence

Fa = Fluorescence after acid

Ve = extract volume (acetone extract; 10ml)

Vf = filtration volume (volume of filtered seawater in liters; 0.528L

S = sensitivity To obtain Fo we need to fill the cuvette, a test tube-like glass beaker, and place into the Fluorometer.  Record data. Then add 3 drops of 10% HCL to cuvette while still in the fluorometer.  Re-read the fluorescence at the same sensitivity setting.  Record data. Making sure in between samples the cuvette is cleaned with acetone. In completing the equation, we discovered that out here most of the chlorophyll is deeper than in most places.  Let’s get to the basics. The ocean can be divided into five broad zones according to how far down sunlight penetrates:

  • The epipelagic, or sunlit, zone: the top layer of the ocean where enough sunlight penetrates for plants to carry on photosynthesis.
  • The mesopelagic, or twilight, zone: a dim zone where some light penetrates, but not enough for plants to grow.
  • The bathypelagic, or midnight, zone: the deep ocean layer where no light penetrates.
  • The abyssal zone: the pitch-black bottom layer of the ocean; the water here is almost freezing and its pressure is immense.
  • The hadal zone: the waters found in the ocean’s deepest trenches.

Plants are found where there is enough light for photosynthesis; however, animals are found at all depths of the oceans though their numbers are greater near the surface where food is plentiful.  So why is more chlorophyll found deeper the further you travel away from the equator?  Well my hypothesis is because all the nutrients are found in the deep cold layers of the midnight zone.  Near the equator and near coastlines upwelling occurs so the nutrients are brought up to the sunlit zone. As you go further away from the equator less and less upwelling occurs so the phytoplankton is unable to thrive in this sunlit zone. The phytoplankton will grow deep enough in the twilight zone to obtain the nutrients, yet shallow enough where photosynthesis can occur.  I also think that like land plants, too much sun can reduce the growth of the phytoplankton.

Chlorophyll fluorescence is often reduced in algae experiencing adverse conditions such as stressful temperature, nutrient deficiency, and polluting agents.  Phytoplankton photosynthetic efficiency is one of the biological signals that rapidly reacts to changes in nutrient availability as well as naturally occurring or anthropogenically introduced toxins (contaminants).  The results can be used as an indicator of system wide change or health.  I finally finished the samples around 3 p.m. Got in a work out, watched a movie and was off to bed but not before we retarded our clocks 1 hour.  We are now entering my normal time zone.  So close to American Samoa yet so far away•