Southern Ocean GasEx Blog

Dispatches from the Southern Ocean Gas Exchange Experiment

The Last Word

Posted by sogasex on April 11, 2008

By David Ho, LDEO

About 3 years ago, I took on the challenge of planning and championing a gas exchange experiment in the Southern Ocean. I had no illusion that it was going to be easy, but I had plenty of help from the group that I assembled, which consisted of leadership from the previous GasEx experiments, and others who were as passionate about understanding air-sea gas exchange as I was. Our first job was to sell the idea to the community at large, and to the various funding agencies. After that, the real planning began.

From the beginning, SO GasEx was going to be a collaborative experiment, requiring everyone involved to work together towards a common goal. Since many of us involved in the planning of this experiment had previously worked on GasEx-98 and/or GasEx-2001, we knew the challenges involved in staging an experiment that requires the ship to operate in very different modes; combining that with trying to operate in the harsh conditions of the Southern Ocean added to the challenge.

On the cruise, every detail, from lab assignments on the ship, to distribution of water from the CTD, to scheduling of different sampling events, had to be planned carefully. As I mentioned in a previous blog, there are various projects on the ship that required it to operate in different modes. Without the cooperation of all participants involved, this would have been a difficult task.

Many people on the cruise made my job easier, both in my role as co-Chief Scientist and as a PI for the 3He/SF6 component of the experiment. My co-Chief Scientist Chris Sabine was a pleasure to work with. He and I shared responsibilities for various tasks and decisions making (and we had to make some difficult decisions). While we were on the same page on most things, sometimes we would disagree but our divergent opinions lead us to compromises and to better solutions than either of us had thought of. I’m most grateful for the fact that Chris took care of navigating the NOAA-specific bureaucracy, which made it a lot easier for me to concentrate on the scientific aspects of the cruise.

Kevin Sullivan did a masterful job of creating the 3He/SF6 tracer patches, and measured all the SF6 samples from the CTD casts. Matt Reid and Paul Schmieder took turns to chase the tracer patches around for weeks, and never lost it (the patch, but I’m not sure about their sanity). Pete Strutton, Dave Hebert, Roberta Hamme, Burke Hales and Bob Castle helped with the study site selection. Geoff Lebon, Steve Archer, Mike Rebozo, Sarah Purkey helped with various aspects of the tracer injection and sampling. Paul Covert and Byron Blomquist helped us with computer issues. Mete Uz, Program Manager of the Global Carbon Cycle Program in NOAA’s Climate Program Office, rallied the troops on land when it wasn’t clear if the ship could stay at our study site in high winds, and made sure that we were able to get back on track. The Captain and the crew of the NOAA Ship Ronald H Brown, in their various roles, ensured that we were safe, well fed, and to a large extent, able to execute our various scientific projects.

I want to acknowledge Kathy Tedesco, former Program Manager of the Global Carbon Cycle Program in NOAA’s Climate Program Office, with whom I worked closely during the planning stages of the experiment. She was professional yet approachable, and without her help, planning for SO GasEx would have been immensely more difficult.

Even though we did not encounter sustained wind speeds in the 15-25 m/s range at our study site, we had periods of sustained winds up to ~15 m/s, which will be a valuable addition to existing measurements of gas transfer velocities from previous experiments and other parts of the global ocean. Also, we encountered a range of wind speeds (see picture below), which should allow us to effectively evaluate existing parameterizations between wind speed and gas exchange.

The experiment had more hours of eddy covariance CO2 and DMS measurements than any other previous experiments, and the most number of 3He/SF6 samples ever taken in one gas exchange experiment. The combination of CO2, DMS, O3 flux measurements with 3He/SF6 measurements of gas transfer velocities is unprecedented; along with ancillary measurements of waves, turbulence, and bubbles from a buoy that was able to remain with the tracer patch, they should allow us to elucidate mechanisms controlling air-sea gas exchange, and determine if these mechanisms are unique to the Southern Ocean. The detailed carbon system (DIC, pCO2, TAlk), DMS, productivity, and phytoplankton measurements could also help us understand what controls CO2 and DMS dynamics in our Lagrangian patch. All in all, I think SO GasEx was a success, and the data will bear this out in time.

Today, we will pull into Montevideo, Uruguay, and the SO GasEx cruise will be officially over; however, the fun is just beginning. Over the next months, the next chapter will unfold, with all the PIs working up their respective data, coming together to synthesize their results, and disseminating their findings to the community at large.

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The entire SO GasEx scientific party on the fantail, taken on the last day before arriving in Montevideo. The weather was completely unrepresentative of what we experienced during our trip, and a welcomed relief to everyone.

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Wind speed histograms from SO GasEx, showing winds averaged over 24 hours and spanning 3 CTD stations, which is the time period necessary for one 3He/SF6-derived gas transfer velocity calculation. We encountered a nice range of wind speeds, from 4 to 14 m/s.

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We enjoyed a nice sunset on our last evening out at sea…

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…and were visited by a school of hundreds of dolphins right after sunset; a nice way to end the cruise.

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Future gas exchange scientists? Kathy Tedesco’s niece and nephew proudly sporting their SO GasEx T shirts.

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P.P.S.

Posted by sogasex on April 12, 2008

By David Ho, LDEO

Well, it finally happened. We were supposed to get in at 2 am, then it was changed to 4 am, then to 8 am, then to 11 am, and we finally docked at 12.01 pm. It was a fitting end to the cruise in 2 ways: The first is just the unpredictability of everything, and the second is that Herb won the pool predicting when we would get in. Herb and Richard from the galley fed us really well the entire cruise, and being a vegetarian, it was certainly the best cruise I’ve ever been on in terms of the food selection.

The agent in Montevideo was great, and had all the containers waiting for us. With everyone helping unload the ship and load the containers, everything going back to the US via ocean freight was unloaded in less than 4 hours. The air freight will go out on Monday.

Now it’s time for everyone from the scientific party to…well…party. We will meet up soon for drinks and food before disbanding and returning to our respective homes.

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After anchoring all night off Montevideo, the moment the ship started moving was probably the happiest moment in the entire cruise for Burke.

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A view of the ship’s berth in Montevideo.

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Shipping containers getting loaded with scientific gear.

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P.S.

Posted by sogasex on April 12, 2008

By David Ho, LDEO

Chris was prescient when he wrote his blog. We were suppose to get into Montevideo earlier today, but it turns out the port had no berths for us until tomorrow. So, it’s 11 pm on Friday night, and we’re sitting in the mouth of the Río de la Plata, a few miles off the coast of Montevideo. We can see the lights of the vibrant city, much like prisoners on Alcatraz could see the great city of San Francisco, but everything the city has to offer is entirely out of our reach. To make things worse, we’re out of honey and Vegemite. It’s officially a crisis.

The scientist and crew onboard all have extreme cases of channel fever. People pass the time by playing board games, watching movies, catching up on work, and sitting around discussion things they miss on land (e.g., favorite foods, activities, etc). We all hope that tomorrow will come soon, and we’ll finally be dockside and unloading our gear. Stay tuned.

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Pete with the empty jar of Vegemite moments before its burial at sea.

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Alejandro and Bertrand engage in an international game of chess.

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Scrabble hawk Bob takes on another unsuspecting victim in Byron, while Geoff and Sarah catch up on some work in the background.

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Silver lining

Posted by sogasex on April 10, 2008

By Steve Archer, Plymouth Marine Laboratory

Back to the weather – it’s the limey again: flying fish off the bow, egrets off the stern, warmth, gentle rolling, blue seas: relief. The ship and folk on it have taken a bit of a pounding over the last couple of days but there’s a lot more of a relaxed atmosphere onboard today. It’s a fine way to finish up. For one, it’s a great day for packing up and clearing up after the gales (see Mike below), especially if you can do it outside. My equipment has to get flown back to the UK then Canary Islands for the next experiment in a few weeks time but first I’ve got to rebuild a couple of boxes that took a ‘green one’ over the side.

However, to a few of us, the high winds and seas that we’ve struggled through on the transect to Montevideo have been a bonus in scientific terms; we obtained what we hope are sea-to-air flux rates and transfer velocities, from the highest winds and biggest waves of the experiment (see photo). If the measurements have been successful this will certainly extend the range of wind speeds over which the fluxes between ocean and atmosphere of DMS have been recorded; shedding more light on what controls the rates of exchange at that critical, high end of the wind-speed-spectrum. Every cloud has some silver lining!

So cheerio to the generally grey, cold and not-so-windy-this-time Southern Ocean; and cheerio to my uncle Chriso who passed away the other day; his enthusiasm for fishing, wildlife, boat-building and the sea had a big influence on me as a child. There will be a lot of fish sighing with relief now he’s gone, amongst many things, he was a master-craftsman-angler; he would have done a decent job of rebuilding those two crates too!

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Mike ‘dries out’

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South Atlantic spray.

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Cheerio to the SO; what a difference a day makes.

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Untitled

Posted by sogasex on April 10, 2008

By Kevin Sullivan, NOAA/AOML

frigid winds froth waves:
quantitate more turbulent
gas exchange. let’s go!

antarctic waters
prickle double gloved fingers -
sample never cease.

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Kevin Sullivan…poet, philosopher, cold

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So close and yet so far…

Posted by sogasex on April 9, 2008

By Chris Sabine, NOAA/PMEL

As mentioned in the last few blogs, we finished our last CTD cast on Friday and started the 1300 mile trek to Montevideo, Uruguay where we will unload the ship and head our separate ways. For those of us used to traveling at the speed of a car or plane, the transit home can literally feel like the “slow boat to China”. When we first left station the ship was making a blazing 12.5 nautical miles per hour (or knots for you sailors). We had high hope of getting into port before our 9 am Thursday schedule, but that all changed on Sunday night.

We had spent the last two weeks before leaving the study site desperately hoping for high winds and rough seas; something, anything to finish off the Southern Ocean Gas Exchange experiment with flair. But it was not to be. We had decent 15-20 knot winds but not the big storm we had all dreamed about as we were writing our proposals. Despite that, we were reasonably satisfied and looking forward to a relatively quick trip home.

Sunday night, however, we drove into that perfect storm and just the kind of conditions we had been hoping for back at the study site. First the wind kicked up to 40 knots then 50 knots. Initially the seas were calm and the wind was just blowing the tops off of the small ocean swells we had been plowing through with ease. Over time, however, the sea started building and the 1000 miles of open ocean between us and Montevideo seemed to grow wider and more angry. With the ship’s vent problems (see the back on track blog), we were forced to slow our progress so we did not get too many bubbles into the ship’s cooling water systems. By late Sunday night the 12 knots had turned into 1 knot and our hopes of getting in early were whisked away on the wind.

Our experience with these wind events over the last month or so had been that they blow through quickly, but apparently this low pressure system liked what it saw and decided to hang around. Monday we ranged from essentially no speed over ground to as much as 4 knots for a couple of hours. Winds were 30-40 knots and the seas were 15-20 feet with the occasional 30 footer just to test that everything was tied down properly. Our hopes of getting in early had changed to hopes of getting in on time but even those looked doubtful as night fell with very little progress towards shore.

Tuesday brought a new promise as we were making 3.5 knots when I woke up. It didn’t really hit me how sad that was until I found myself on the treadmill running twice as fast as the ship. On Tuesday the winds were a little better, 20-30 knots but it was still impressive to sit in the staging bay looking out over the fantail and watch the waves break over the side and stern of this ship. At least the atmospheric flux guys are getting some measurements out of this. Most of us have completed all the packing we can do for now and are desperately trying to think of ways to entertain ourselves. It is difficult to focus on anything when the whole world is tossing and turning. At least we all have our sea legs so seasickness is not too much of a problem.

Now it is Wednesday. The winds have dropped a little more and the seas are starting to calm as well. We still have a little less than 500 miles to go, but we are hopeful that we are through the worst of it and conditions will only improve from here. I suppose only time will tell.

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Crew and scientists on the fantail tying down items battered by the rough seas

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The CTD against a backdrop of whitecap covered ocean that we rarely saw at the study site

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(Cor)relation for Air-Sea fluxes

Posted by sogasex on April 8, 2008

By Alejandro Cifuentes, University of Connecticut

Let me introduce you to my good friend the correlation function (whom you may already know well) and its relevance in the air-sea flux calculations (momentum, energy and mass). The correlation function is a powerful statistical tool, specifically in the analysis of time series measurements. The combination of the time averaged measurement of a normally distributed random series coupled with the correlation function can ultimately define the behavior of the series. As we try to understand and interpret nature’s behavior we are typically given the response of a suite of physical variables that are arranged in time (i.e., wind velocity, temperature, relative humidity, pressure, CO2 concentrations, etc.). Ultimately the correlation function becomes a consistent statistical approach for digesting the data and supplying a physical interpretation.

So consider the fluctuating time series of wind velocities, applying the correlation function will tell us about the momentum exchange. The energy flux (vertical transfer) transported as sensible heat can be described by the correlation function applied to the vertical wind velocity fluctuation and temperature fluctuation. Ultimately, the mass flux (vertical transport) is determined as the correlation between the fluctuation of a compound (i.e. CO2) and the vertical wind velocity fluctuation. This method evolved into what is now known as Direct Covariance (a.k.a. the Eddy Correlation) Method, recently introduced to me (just six months ago) by my advisor Dr. James Edson as I stepped into his domains of the Air-Sea interaction. The whole process has become increasingly familiar with time, especially the power of the correlation function which has yet even more to offer. Based on it, a spectral analysis of the series via Fourier transform can be developed and more information can be squeezed out of our precious time series. This describes very roughly the use and the power of the correlation function in the flux calculations and the concept behind the Eddy Correlation Method. For details on the procedure and hardware required on this process I recommend checking Ludo’s recipe posted on the blog: “Shake and Bake” … baby!

The correlation function is not to be confused with the relation function for the fluxes; the relation concept might escape the realm of statistics, but is no less fascinating. Remember, four cooks in the kitchen…the relation function here is defined as any interaction (you can read correlation too!) between us, the cooks (a.k.a. the CO2 flux team). Before February 22nd, I didn’t know Chris Zappa (or Dr. Zap, an evil doctor with unholy snoring powers, but with great advice regarding work), Ludovic nor Byron. Through time, the domain of our relation function has grown in both appreciation and complexity. Ludo and I have worked in tandem during much the SOGasEx campaign. As you might expect, a good relation developed. Our electronics were no exception; they too felt the power of the relation function. Our Data Acquisition Systems (DAS) began to mimic one another. Without fail, if Ludo’s DAS crashed, mine would follow (a stochastic process? I think not!). The Licors 7500 adopted the same tendency. In the end, a good relation function was able to do the trick, for the sake of the experiment but mainly for the sake of the fluxes.

So you can imagine we went through on the Brown for nearly two months time: discussions, arguments, chats, advice, guidance, laughs, dancing, a lot of singing and some more laughter. One certainty: all the variables helped to achieve our overall success.

PS: Kate, thank you once more for your help editing.

Below is a look to our highly Entropic Data Acquisition Systems.

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GASEX-DAS I: Not to be deceived, high entropy levels got nothing to do with disorder or chaos!

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DAS II: Ludo’s system, maybe reaching its own “Heat Death” …

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Air-Sea Interaction: It’s happening, can you see it? … Look at those fluxes!

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Tiny Bubbles

Posted by sogasex on April 7, 2008

By Carlos Del Castillo, The Johns Hopkins University-APL

The loud popping sound was immediately followed by pressurized 4°C seawater being sprayed all over the room. We are working inside the wet lab on board the NOAA Ship Ronald H. Brown (see Richard’s blog entry) and one of the clean seawater lines that feeds our instruments just burst. A high-pressure water line does not just burst and calmly spills water. The line swings left and right, up and down, squirting water on everything and everyone. But no worries, we are in the wet lab. It is supposed to be wet. Before the indoor shower, we had settled into an easy, boring routine for our long transit to the proposed research site, so the burst line was almost a welcomed distraction. Almost welcomed because a busted line means some data will be lost, and the inevitable invasion of air bubbles into our system. We do not like bubbles in the wet lab. Air bubbles dramatically change the optical properties of water and create a lot of noise in our data. Bubbles must be dealt with. Bubbles are the enemy. We battle bubbles along three fronts. The water that flows through our optical instruments enters the boat through an intake that is several meters below the sea surface. There are not many bubbles at this depth unless the weather is bad. Weather is almost always bad in the Southern Ocean. The second line of defense is a “debubbler.” This plastic contraption uses a vortex to trap bubbles and send them back to the ocean – where they belong- while tunneling bubble-free water to our instruments. Bubble-free water is good. In our quest for bubble free water we keep all the lines that feed the instruments submerged in a water bath as our third line of defense. By doing this, we keep the water inside the lines very cold to avoid degassing– or the formation of un-welcomed bubbles that will eventually migrate to our instruments. In this case, the water bath is a large sink where we also keep the instruments to avoid temperature fluctuations. The water in the bath is the same 4°C seawater that flows through the instruments.

In this expedition we encountered our first un-welcomed bubbles in bottled water. As in most countries, bottle water in Chile can be found in two varieties, sparkling water and regular water, or “agua con gas y agua sin gas.” Sparkling water seems to be the most popular and the default offering unless otherwise specified. So, if one does not add the “sin gas” modifiers, one may get bubbles. Agua con gas is not all that bad, we are just not used to it. The wet lab gang prefers to drink our bubbles with beer.

Our instruments in the wet lab measure several parameters. We have two acs’s (absorption, attenuation, spectral) that measure light absorption and attenuation from ~400 through ~700 nm at 4 nm resolution. These are the successors to the veritable WET Labs ac9 (same measurements but at 9 wavelengths). Light attenuation is measured along a fixed path length and represents the loss of incident light due to light absorption by chromophores (i.e. colored dissolved organic matter –CDOM- and photopigments), and losses due to light scattered away from a narrow detection angle. The absorption measurements include incident light losses due only to absorption by chromophores. The measurements are achieved by using two cells, or in this case plastic flow through cylinders. The attenuation tube (c) has an opaque inner wall so that scattered light is absorbed by the tube and counted as light loss. The absorption tube (a) has a highly reflective inner wall so that light scattered forward and away from the direction of the incident light field is not absorbed by the inner walls and reaches the detector. The cell in this case works as a waveguide. Clearly, backscattered light is lost, but most of the light scattering is forward scattering. In addition we have a Turner Designs C-6 fluorometer that measures the fluorescence of CDOM and phytoplankton, and a ctd that measures salinity and water temperature.

The color of a substance is an expression of its chemical characteristics. In the case of seawater, its optical properties – or its color – can give us information about the concentrations of chlorophyll and organic matter in seawater. These measurements are very important to further our understanding of the carbon cycle. Our instruments only measure these parameters along the thin line that is the track of the research vessel. However, several NASA research satellites are equipped with ocean color sensors that provide daily coverage over the globe. The data provided by these satellites are essential to our understanding of the global carbon budget and climate change. Data from these sensors, however, has to be interpreted using complex mathematical algorithms. These algorithms are created and validated using field data like the data provided by our instruments in the wet lab. Curiously enough, satellite ocean color sensors can be affected by bubbles. White caps (or “espuma”) formed in the ocean when winds exceed ~ 14 knots, are nothing more than bubbles at the air-sea interface. White caps change the optical properties of surface waters making it more difficult for the satellites to detect the true color of the ocean. Also, bubbles injected into the water column by large braking waves interfere with satellite color measurements. Again, bubble-free water is good.

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So, here we are in our wet lab, happily bubble free and drinking liquids without gas – at least until the next water line bursts.

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The tangle of hoses that is our underway system

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Scott Freeman (standing on the right) and Carlos Del Castillo (with the funny hat) calibrating one of the acs’s using pure water.

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Carlos Del Castillo cleaning the interior of one of the optical tubes of an acs.

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Last Cast

Posted by sogasex on April 7, 2008

By David Ho, LDEO

A couple nights ago, we had our last CTD cast (see below) and are now on our way to Montevideo. We’re scheduled to arrive on the morning of April 10th. While I doubt any of us miss sampling from the CTD, least of all Paul and Matt who had to find the center of the tracer patch at 9 am and 9 pm, it did provide a nice routine to the day. Now, I just see people wondering around the ship aimlessly, overwhelmed by their newfound freedom.

As Pete mentioned in his blog, once the CTD is on deck, it is sampled in order of time sensitivity. Gases go first, in the order of their volatility, and then other things like nutrients and particles. There are varieties and different levels of complexity in people’s sampling methods:

  • My method for 3He is by far the loudest (involving banging the aluminum channels with a dead blow hammer, and then tightening stainless steel clamps with an impact wrench). It’s no doubt one of the reasons why many people are happy to be done with the CTD.
  • Roberta’s other nobel gases takes the most amount of time (read about it here).
  • SF6 is pretty standard, but it’s imperative that Kevin doesn’t get any bubbles or a headspace in the sample.
  • Sara and Roberta sample oxygen in a funny looking bottle, and measure the water temperature during sampling. They add reagents before capping the bottles, and then shake the bottles rigorously.
  • Bob, Geoff, and Paul are responsible for the CO2 parameters (pCO2, DIC, TAlk), and all those samples need to be poisoned to ensure that biological activity doesn’t alter the sample in the bottle.
  • Steve is by far the most stealth sampler. He stands in the background with his bottles ready to sample DMS, and has the bottle numbers written on his hand (or rather, glove; while the rest of us use sample sheets). When it’s his turn, he just shows the bottle to the sample cop, and then samples from the appropriate bottle. Contrast this with the rest of us, who yell out our sample numbers to the cop.
  • Unlike most of us, Carlos doesn’t use a noodle (either Tygon or silicon tubing) for his samples, because they could contaminate his DOC samples.
  • Charlie always shows up right before he’s due to sample (and all of us yell “Charlie!” like they called “Norm” when he came into Cheers), and holds about 5 (small) bottles for nutrients in his hands and samples the bottles rapidly, also sans noodle.
  • Scott seems to have the easiest sampling gig. He only samples one Niskin bottle, and gets the whole Niskin bottle to himself. He connects his noodle to the bottle and drain the entire content into a small drum. He finishes by opening the bottom of the Niskin bottle and draining the rest of the water and suspended solids into a contraption that looks like a beer funnel.
  • Pete, Dave, Veronica, Bob, and Bruce then basically takes all the water that is left for productivity and filtering for chlorophyll and particles.
  • Sara bats clean up, and takes 2 samples for salinity per CTD in bottles that resemble old medicine bottles.

All of this takes about an hour, after which some people start analyzing their samples, while others wait to ship the samples back to the lab for analysis.

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The group poses in front of the last CTD cast before sampling

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Sampling for 3He

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Sampling for oxygen

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Sampling for pCO2

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Bye Bye Buoy

Posted by sogasex on April 5, 2008

By Christopher Zappa, LDEO

A previous blog entry discussed the carbon measurements from the MAPCO2 buoy using SAMI-CO2 systems, while another post explained how the buoy tracks the patch with the help of the holey sock drogues. The MAPCO2 buoy allows us to measure physical processes very near the ocean surface that we typically can’t measure from the ship because the ship disturbs the flow of the ocean. My project employed a variety of instruments that use sound to measure the ocean currents based on the Doppler velocity backscattered from particles in the ocean. Dave Hebert talked about how he measures the ocean currents using the ship’s ADCP to track the tracer patch. One instrument we use on the buoy is a high-resolution ADCP to measure the currents much closer to the ocean surface. Instead of profiling 1000 m as the ship’s ADCP, this “Dopbeam,” as we call it, measures the profile of velocity over 1 meter with 1-cm bins. While the wind puts energy into the waves that eventually break, the wind also controls the near-surface ocean currents directly and through wave breaking. These fine-scale near-surface currents eventually become chaotic, or turbulent, and develop very small “eddies,” or energetic circular motions. Wave breaking will also generate these fine-scale turbulent eddies. We measure these fine-scale near-surface eddies that mix up the top few meters of the ocean and that work to regulate the gas transfer.

A few days ago, the MAPCO2 buoy was taken out of the water…for the third and final time. Each time, getting the buoy on deck is only half the job. Scientists scurry quickly to download the data that have been accumulating on the instrument. This is an essential task in order to make sure that all is well while the buoy was in the water. Luckily, we had only one problem during all three deployments combined. On the final retrieval, the underwater camera housing was flooded and the camera was damaged (see picture below). Damage caused by the ocean is always a danger with any instrument that goes over the side of a ship and remains underwater for days and weeks on end.

Now that the buoy is out of the water and all the data have been collected, I have only a few systems running (WaMoS II and the wave breaking video). Slowly, there is a sense that the cruise is over… and it’s a little sad. There are signs throughout our day that the experiment on site is coming to a close. Today, we had our last Fire and Abandon Ship Drills. In fact, as I write this we are performing our last CTD of the experiment. After that, we set sail for Montevideo, Uruguay. Even the king penguins were sad to see us go. Soon enough, we will be back on land, getting rid of our “sea legs.” There will be no more crawling into the small bunks, no more rolling back and forth as we sleep. No more day-to-day monotony of data gathering. Nope, we can finally have a nice, frosty, ice-cold, refreshing BEER. And watch the Red Sox beat the Yankees at Fenway. OK, maybe I’m not so sad.

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Dopbeam mounted in its titanium cage being prepared to be deployed from the MAPCO2 buoy. The Dopbeam is roughly 2 feet long and 3 inches in diameter.

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Retrieval of the MAPCO2 buoy with the Dopbeam mounted in its cage chained below.

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Underwater camera housing mounted on MAPCO2 buoy before deployment.

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Underwater camera housing after third deployment. The housing is flooded with ocean water. Notice the orange rust at the top.

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Camera damaged by the ocean water.

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Even the penguins, which flock around the CTD every day, were sad to see us go.

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