News

S4P: 10 MAR 2011 (REPORT) Oct 2, 2013

The storm which stopped our work last Thursday morning finally abated early Saturday. Since then we have been working steadily on our measurement program, without weather or equipment delays. We are making good progress, though remain about 5 days behind the expedition deadline timeline. Small problems pop up in the equipment from time to time, and we have found some ways to improve a few procedures - pretty much business as usual. Data quality remains excellent. No surprise that the Circumpolar Deep Water and its closest relatives remain consistently warmer and slightly saltier than observed during the Akademik Ioffe S04P cruise in 1992.

We will soon turn from our eastward course and follow 150°W south to the Antarctic continental shelf, which will complete for the first time the far south end of WOCE/CLIVAR/IOCCP line P16. Then it will be decision time for the first cuts to the science program. The Palmer is steaming mostly at 9 knots to conserve fuel, and has quite understandably had to slow in fog at night in waters where there are hazardous growlers and bergy bits that do not show up on the radar. Not to mention that there is plenty of stormy weather out there, just missing us at the moment. Because we can make up four days simply by widening station spacing to 60 nmiles on the eastern half of the 67°S (S04P) section, we are not in an insurmountable situation regarding the present time deficit, but we are still considering a 3-day cut (the sampling along 170°W, from 73°S to 67°S), which has been discussed with the oversight committee and team PIs. Watch for next week’s report for our decision.

Small breaks provided by nature the past week include icebergs (the reliable scenic highlight of working near Antarctica), the Aurora Australis a few times (we’ve included two photos shot - see above right and below - by Juan Botella, our PolarTREC teacher), and a close-up visit by a few humpback whales.

The galley staff is great at keeping morale (and waistlines) at a maximum. Fresh bagels made a surprise appearance, the cookie supply seems endless, the meal entrees are as tasty and varied as ever (with some excellent vegetarian dishes, too). No one is surprised that the fresh vegetable supply is dwindling

• lettuce is gone now, for example.

We have not yet accounted for the date line in our current ship’s day/date, so enjoy the odd situation of now being on the same time zone as Hawaii, but one day ahead. We have not yet changed day/dates mostly due to our plan to go back to 180°W to start a cross-shelf section after we complete the 150°W section and two mooring recoveries, though I confess that the notion of switching one week from today - thus having two March 17th’s (St. Patrick’s days) - may have entered our minds.

This is a harmonious, very good natured bunch. Cribbage and foosball tournaments are in full swing, groups linger at meals to enjoy conversations, music is heard from time to time. All is well aboard the Nathaniel B. Palmer.

Jim and Alex

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S4P: 09 MAR 2011 (LETTER) Oct 2, 2013

Dear Family, Friends, and Colleagues,

What is remarkable about most of the past week may be how unremarkable it was: after a long storm (our 4th!) which stopped our work last Thursday morning finally abated in the wee hours Saturday, we have been working steadily on our measurement program, just as we usually do and expect to do on these cruises. We are making fine progress, though are about 4.5 days behind the expedition deadline timeline. Small problems pop up in the equipment from time to time, and we have found some ways to improve a few procedures - pretty much business as usual. (I’ll get into our science program in future letters.) The sameness of the work - we are either on station or steaming between stations around the clock - is an oddly comforting measure of progress. Of course, we very much enjoy the little breaks nature provides…

Icebergs are a reliable scenic highlight of working near Antarctica, and when we chance upon one on a sunny moment (one of my photos is attached) or at sunrise or sunset (attached unenhanced sunset photo taken by Aimee Neeley on the right), it’s time to bring out the cameras.

Along with some clear periods during days has come some clear periods at night, and we have seen the Aurora Australis (“Southern Lights”) a few times. Our PolarTREC teacher, Juan Botella, captured some excellent night photos from a moving ship (!). I have attached two (See left and below), enhanced for light level only. Notice the stars of Orion’s belt in one of them?

A few humpback whales visited the ship the other day, playing around (or feeding?) a bit before swimming off. Juan captured some nice photos (one is attached - see right). Nature is not the only source of welcome breaks: the galley staff is great at keeping morale (and waistlines) at a maximum. Fresh bagels made a surprise appearance, the cookie supply seems endless, the meal entrees are as tasty and varied as ever (with some excellent vegetarian dishes, too) - and I don’t know what it was about Mexican night, but just about everyone went back for seconds. Of course, because the ship was resupplied in that garden spot known as McMurdo, no one is surprised that the fresh vegetable supply is dwindling - lettuce is gone now, as expected.

This is a harmonious, very good natured bunch. Cribbage and foosball tournaments are in full swing, groups linger at meals to enjoy conversations, music is heard from time to time. All is well aboard the Nathaniel B. Palmer.

Jim Swift
Chief Scientist
NBP-1102 / S04P

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S4P: 10 MAR 2011 (REPORT) Oct 2, 2013

We began our work off Cape Adare, a location notorious for high winds. Indeed, seas and swell have already disrupted CTD operations on Nathaniel B. Palmer four times, with 84 hours lost to date (the equivalent of 18 stations). The Palmer rides the storms well. The captain and mates choose a heading and slow speed that will provide a reasonably good ride, and try to judge when to head back to the next station just in time for the seas to have improved post-storm to the point where we can go back to work. During the biggest storm, during a long spell of sustained winds over 50 knots, a storage van on the fantail was partly caved in by a wave.

At one point while we were waiting out a storm near an intended station location, we entered a field of rotten first-year sea ice leftover from the summer melt. We quickly prepared the rosette, knowing that in the ice the large seas would be damped down, and, indeed, we got a station done despite the weather. Meanwhile we passed by some crabeater (See left) and leopard seals hauled out onto the ice, making a nice photo op.

It’s not all been storms, of course. The team is working diligently and every measurement program is going well. Water sample data are being delivered to the onboard data system by all the groups, and the data processors update the data files regularly. We already have some exciting science results: significant changes since 1992 in seawater temperature and salinity along our transect of stations NE from Cape Adare. The cold, salty Ross Sea Bottom Water dense outflow so prominent in 1992 on the west end of the S04P section is now gone, and the Circumpolar Deep Water offshore is warmer and saltier than it was 19 years ago. We’ve included a figure and Alex’s scientific caption to whet the appetites of the PIs ashore.

The food is great (some of us already fear we may be getting great ourselves). All hands - ECO, RPSC, and science guests alike - enjoy the friendly and productive atmosphere on board. The ECO engineers and RPSC staff have been very helpful in quickly solving any problems that arise. We may get a tiny bit frustrated during the storms - we came here to work, after all - but we are a happy bunch.

All is well.
Jim and Alex

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S4P: 09 MAR 2011 (LETTER) Oct 2, 2013

Dear Family, Friends, and Colleagues,

One of the inescapable aspects of working in the Southern Ocean is storms - both the ones that hit directly and the more distant ones that generate the long, rolling waves known as swell. The Southern Ocean may be the stormiest large-scale environment on earth - I don’t know that for certain but it feels that way. Big low pressure systems (storms) develop and evolve to circulate around Antarctica in a steady parade. Our mote in the ocean - the Nathaniel B. Palmer - has been hit three times so far by storms with winds well over 40 knots (equals 46 statute miles/hour), plus the ship is always affected by swell (sometimes quite large) propagating from distant storms. We can work in wind and swell to a degree, but we have already had more than 77 hours of down time when the seas were too rough to work.

As part of our cruise support, we receive weather forecasts customized to our location. In the old days such forecasts were next to worthless, but with the advent of weather satellites and computer models, we get a day or two warning of each storm. So what do we think when we hear a storm is forecast to affect us soon? Well, officially it’s “get as much work done as we can and get everything tied down”, but unofficially it’s also “get to the laundry before the storm hits”, because the laundry machines must be shut down during storms in order to avoid damage to them caused by ship motion.

The Palmer rides the storms well. The captain and his officers choose a heading and slow speed that will provide a reasonably good ride, and try to judge when to head back to the next station just in time for the seas to have improved post-storm to the point where we can go back to work. We have work to do, but the pace definitely slows with no new samples to analyze. Some people suffer more than others from seasickness, though the fortunate majority of us have now adapted to the ship’s motion in stormy seas.

The biggest storm, with a long spell of sustained winds over 50 knots, caused some damage: a storage van on the fantail was partly caved in by a wave. A photo frame from the ship’s stern video camera (See left) shows a large wave breaking over the fantail. You can see why we do not go out on deck in heavy seas or storms!

I have been asked, “how much ‘bad weather time’ did you allow when you planned the cruise?” The answer may surprise you: none. With the cost to taxpayers of a research cruise like this running in the $100,000/day range, one cannot justify extra funds for contingency expenses. And, anyway, this cruise is already near the Palmer’s maximum duration at sea (mostly determined by fuel) for our type of work. What I do have is a maximum science plan that will accomplish all objectives within the allotted time, and the responsibility to make the best cuts to it (if needed) at the best times so that we accomplish our highest priorities while still ending up at the last planned station shortly before the time, barring emergencies, that we must head to port.

The other day, while we were waiting out a storm, I noticed we were entering a field of rotten first-year sea ice leftover from the summer melt. Aha! I asked the gang to prepare the rosette and alerted the deck tech and bridge: I knew that in the ice the large seas would be damped down and we could do our station. The mate on watch kept us in a small patch of open water in the midst of the ice field, and everything worked out great. Meanwhile we passed by some crabeater and leopard seals hauled out onto the ice (photos attached - See above right and below). [Quick, how can you tell, when you see a seal on the ice, if you are in the Antarctic or, instead, the Arctic? If you can come right up close to the seal, you are in the Antarctic, and if the seal dives in the water at first sight of you, you are in the Arctic. The difference: polar bears (an Arctic-only predator).]

We already have some exciting science results: significant changes since 1992 in seawater temperature and salinity along our transect of stations NE from Cape Adare. We’ll soon send early results to the science team ashore to whet their appetites.

The food is great (some of us already fear we may be getting great ourselves), and all hands (ECO, RPSC, and science guests alike) enjoy the friendly and productive atmosphere on board. We may get a tiny bit frustrated during the storms - we came here to work, after all - but we are a happy bunch.

All is well aboard the Nathaniel B. Palmer.
Jim Swift
Chief Scientist
NBP-1102 / S04P

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S4P: 24 FEB 2011 (REPORT) Sep 30, 2013

Our cruise for the NSF and NOAA-sponsored US Global Ocean Carbon and Repeat Hydrography Program will cross the far-south Pacific sector of the Antarctic region on the US Antarctic Program (USAP) icebreaking research ship Nathaniel B. Palmer. We are scheduled for a 60-70 day voyage from the USAP McMurdo base to Punta Arenas, Chile. This cruise is unique for the program in that it is being carried out from a USAP ship operated by a commercial operator, Edison- Chouest Offshore (ECO) (under charter to the US National Science Foundation), with pre-cruise planning, shipping, logistics, and on-board science support from a second company, Raytheon Polar Services Corporation (RPSC) (via contract with the US National Science Foundation).

Our science team assembled in Christchurch, New Zealand, where we attended a pre-ice-flight briefing and cold weather clothing issue, and on 14 February flew to the ice sheet runway near Ross Island via a US Air Force C-17 transport. Although cancelled flights and “boomerangs” (flights turned back by weather or equipment problems) are frequent, our flight went without incident. The science team was excited to be in Antarctica and had two days to enjoy the unique amenities, scenery, and recreational opportunities at the base, including a guided tour to Robert F. Scott’s 1902 “Discovery Hut” at Hut Point on Ross Island.

We soon discovered that much of the S04P “do not freeze” cargo was for reasons not yet explained sitting outdoors in sub-freezing conditions at McMurdo, despite our use of the proper procedures, forms, and labels required for “do not freeze” cargo items. In the end the chief scientific damage was to the Argo float program, which was cancelled with all 17 floats shipped back to the USA. By what appears to be a blind stroke of good fortune, the one “do not freeze” cargo container which had been kept above freezing contained the salinity and carbon seawater standards - with the loss of either the expedition would have been cancelled. Some other cargo had been water damaged at some point during transit, then was damaged by mold, then frozen, but the direct losses to the science programs from that damage were minimal.

The science team boarded the ship midday on 17 February and soon set to unloading scientific cargo from the 5 20-foot container vans and setting up the CO2 lab van (a trace metal lab van was already at the ship from the previous leg). All RPSC staff on the ship (staff from the previous cruise plus staff from the S04P cruise) plus all ECO personnel were friendly and extremely helpful. Lab set-ups went very well, again with RPSC and ECO personnel efficiently providing assistance. Because the ship was refueled upon its arrival, cargo loading and lab set-ups were delayed, making it necessary to delay the ship’s departure one day from the plan.

RVIB Nathaniel B. Palmer departed McMurdo Base at noon local time on 20 February 2011 in good weather, into McMurdo region waters nearly free of sea ice. The planned transit to the first station on the S04P line was estimated to be approximately two days, barring stops. On the 21st the science team held two test/training rosette casts with the large 36-place rosette. Only minor problems were encountered, all fixed in short order. The evening of the 21st the trace metal team carried out a trace metal cast of opportunity, making up a station from the previous cruise lost to weather.

During the 22nd, as the ship neared the location of the first S04P station off Cape Adare, winds rose well past 30 knots, then 40 knots. It was thus necessary to wait until 1000 local time on 23 February to begin the S04P transect stations.

After nearly two weeks of travel from the US, cruise preparation at McMurdo, and transit to the northwestern Ross Sea, it was a joy to begin work. Weather conditions have been good, and we have almost completed the portion of our transect across the Ross Sea deep outflow with virtually no problems … an outstanding beginning.

Food on board is excellent, relationships between all on board friendly and productive, the ship itself lovingly-maintained for productive research and pleasant life on board. Some of our colleagues and hundreds of RPSC personnel being flown out of McMurdo (as it switches from 1000-person summer staffing to a 200-person winter complement) were caught in Christchurch by the latest earthquake. We have heard that the people we worked with on board are safe, though many were separated from their belongings, passports, and so forth, and face many difficulties along with those endured by the residents of that lovely small city. Our thoughts are truly with them.

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S4P: 19 FEB 2011 (LETTER) Sep 30, 2013

Dear Family, Friends, and Colleagues,

Most things are going well, with a few exceptions (more or less as usual). We took shuttles to the ship Thursday after lunch, and after a quick introductory tour and some safety reminders, we began unloading our cargo from the container vans that had been shipped south from California in December. We had six 20x8x8 foot vans, plus there was quite a bit of loose cargo that arrived by air. I heard someone say we loaded 90,000 lbs of cargo.

The RPSC techs here were efficient in getting a van onto the deck, where our team would unload it like a swarm of army ants, then RPSC would swing it back down to the dock and replace it with another. There was deck space for two vans at a time so we worked nearly continuously. I thought we would be working into the night, but we got all the main load done before dinner, with most boxes in the correct lab. There was lots of sorting out to do, and some more items came Friday morning, but even before Thursday’s dinner people were setting up equipment.

We still do not know the full extent of freeze damage caused by someone allowing most of our “Do Not Freeze” scientific cargo to freeze, but it appears to be light. Miraculously our seawater standards for salinity and carbon were in the one van that was kept above freezing - if either had frozen I would have had to cancel the cruise.

Mary Johnson (our CTD data processor) noticed mold in some of the computer- related boxes she was unpacking, and soon found damp, moldy office supplies and manuals, and more mold in other boxes. There were several plastic tote boxes with four or more inches of water with moldy, now frozen, contents, and others with some water/mold. The only thing we can figure was that someone took these items out of the well-packed SIO cargo container in California when it was raining. Then the wet items molded on the trip south and froze in the Antarctic. I lost all my office supplies and my back-up hard drive (frozen solid in a block of ice), and some of my sea clothes are now battered and splotchy after being washed twice in hot water and bleach. Thank goodness I am very conservative about my packing - because I have enough sea clothes to get by, and I brought a second back-up hard drive in my luggage. Fortunately the bassoon I brought - shipped in that same container - was dry and fine.

There have been a couple of Adelie penguins (one either old or molting - See left) hanging around near the ice pier and one molting Emperor penguin, too (see photos). I also attached a photo of the Palmer at the ice pier, and a shot of me (See above right) after I walked out of the Air Force C-17 onto the ice shelf runway near McMurdo.

As some of you know, I am an amateur bassoonist, playing in the La Jolla Symphony (look them up on YouTube; I suggest the “Frog’s Eye” performance as a good starter). The symphony’s first bassoonist, Tom Schubert, loans me a bassoon of his to take on my trips (probably hoping it will improve my playing!). To accompany the photo of me playing Tom’s bassoon at the North Pole in 2005, I have attached a photo of me playing in Antarctica this morning, with the 109-year-old Scott “Discovery” hut in the background. It was windy, about 18 °F, with light snow. My fingers were cold, and the sound was not so good, but no matter: I did it! (Thanks, Tom!)

We leave at noon tomorrow (the 20th on this side of the date line), a day later than planned, but necessary due to the sequencing of events dictated by McMurdo’s closing for the winter in a couple of days. I have a great team here, and the ship’s crew and RPSC staff are very supportive. The steward and the chief engineer (both key people and both great) remember me from 2003. The captain and I enjoy each other’s company. So it’s already feeling like a “sea family”. I’m optimistic that we have an enjoyable and successful venture ahead.

By the time of my next message we should have completed our test casts and be starting our scientific work off Adelie Land in the northwestern Ross Sea. All is well.

Best Regards,
Jim Swift
Chief Scientist
NBP-1102 (S4P)

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S4P: 17 FEB 2011 (LETTER) Sep 30, 2013

Dear Family, Friends, and Colleagues,

Greetings from Antarctica! Our team traveled from our homes first to Christchurch, New Zealand, where we assembled and enjoyed the sunny weather and green gardens before our trip south. We had been told ahead to pack a “boomerang bag” which we would take with us if our flight to Antarctica was turned back en route by fast-changing Antarctic weather, because we would not get all our luggage back until we finally made it to Antarctica. (We found out that the record for consecutive boomerangs was seven!) We had also been told that certain items were required in our carry on bags, which had to fit under our seats. We thought these were one in the same so were quite relieved to be told during the pre-flight briefing the day before our flight that the boomerang bag was just one of our checked bags.

Our 5-hour flight from Christchurch to McMurdo was on a US Air Force C-17 transport. The flight was smooth (and noisy - we wore ear plugs), and the bag lunch they gave us enough for two. We got to take turns going into the cockpit to take photos of Antarctica from the aircraft. The landing was super-smooth and then, Wow!, we stepped out and found ourselves on this giant ice sheet in Antarctica, with a smoking Mt. Erebus in the background! The US Antarctic Program (USAP) staff took us in large polar transporters across the ice sheet and then around roads to the McMurdo base. On the way we saw penguins, seals, the New Zealand base, and more great bleak Antarctic scenery. We had a quick orientation briefing, were issued room keys and linens, told where to get food and our luggage, and given a schedule for a few events we’d want to attend.

The large USAP McMurdo base resembles a clean, well-run polar mining town with about 1000 residents. There are no commercial activities, but otherwise it has just about everything you’d expect: dorms, a cafeteria (serving a variety of hearty food), a small store, post office, coffee house, bar, labs, gyms, support buildings ad infinitum, lots of heavy equipment, warehouses, fuel tanks, etc. Impressive attention is paid to waste management, recycling, and environmental stewardship, making it one of the cleanest towns on earth. There is a port - open only a very short time each year, and that only after break- in by a heavy icebreaker - with a man-made pier made of reinforced ice. There are hiking trails and historic sites. We had a guided tour to Robert Scott’s “Discovery Hut” from 1902, close by the base (seehttp://en.wikipedia.org/wiki/Discovery_Hut). While anyone can walk there, because we had a guide we were allowed inside, seven at a time. In the “freeze-dried” environment of Antarctica, everything down to animal carcasses awaiting skinning and boxes of supplies was just as it was, and is being left that way for the future.

Speaking of “freeze-dried”, that’s how we felt after walking back from the hut to the base into a stiff and very cold wind - evening air temperature had dropped to 5 degF - the term “wind chill” (in that case well below -20) was certainly appropriate! (In Christchurch the USAP issued us cold weather clothing, and we were glad we had it.) But for the most part temperatures have been in the teens, and today’s 23 degF and light winds make it feel almost balmy. Our ship, the research icebreaker Nathaniel B. Palmer, arrived yesterday morning and fueling began immediately. (The McMurdo base reverts to its 200-person winter status this weekend and the fueling crew needed to get done so they could head home.) The departing science party will be off the ship this morning, and we board and begin loading right after lunch today.

There have been many little hiccups along the way, and one giant one: Much of our “do not freeze” cargo was inexplicably left sitting out in sub-freezing conditions, despite being correctly and unmistakably labeled as “Do Not Freeze”. (There are procedures for this, beginning with a cargo plan before we even ship the items from our labs, and every group affected by this incredible blunder had followed instructions perfectly.) Even the ship’s “do not freeze” food was sitting out in the cold. One container of our DNF cargo was correctly kept above freezing, and by some miracle that contained the standards for salinity and carbon, without which we would have had to cancel the expedition. But the Argo floats - worth $500,000 - were not so lucky, and must be shipped back, unused. (They would have provided the first winter CTD casts from much of this region.) We will not know the extent of damage to our other programs until we begin measurements, but we are hopeful that we can work around most problems.

We have a very good team for this cruise. I enjoy the way everyone gets along together and can tell already we will work together well as one team. I met the Captain last night, and was impressed in every respect. Our on-board Raytheon Polar Services Corporation support staff are a good bunch. So prospects are good for our upcoming voyage. Last night we all unwound in the bar, and in a few hours we begin loading. I’ll report again when we leave port.

Best Regards,

Jim Swift

PS - Because I do not go onto the ship’s very limited email (james.swift.guest@nbp.usap.gov) until tomorrow, I can send lots of photos today from the McMurdo base internet:

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S4P Map Sep 27, 2013

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Trace Metals Sep 25, 2013

There is no dust over the Southern Ocean. Not enough for plants, at least. Most dust particles are soils dragged from the continents by winds. Antarctica is a desert, but the dirt there is locked under ice, and the winds that blow around Antarctica bring no dust to the surrounding oceans.

This poses a problem for phytoplankton; dust carries iron, a nutrient plants need to grow. In most oceans, plant productivity is limited by shortages in nitrate and phosphate, nutrients they use in abundance. In the surface waters of the Southern Ocean, however, scientists find an excess of nitrate and phosphate, which leads them to realize that productivity in the Southern Ocean is limited by the scarcity of iron.

It was different during the last ice age, when there was less CO2 in the atmosphere than now. One major difference between land and sea plants is that the latter can be buried in the ocean floor after death, removing CO2 semi- permanently from the atmosphere. Scientists believe that lower CO2 levels during past ice ages may be partly explained by more productivity in the oceans. Plant growth in the Southern Ocean is now iron-limited, so they reason that it must once have contained more iron. In the prevailing theory, colder and stronger ice age winds enabled dust from the continents to reach the outermost parts of the oceans. Plants thrived, taking more carbon into the ocean sediment when they died.

Climate change modelers make projections of atmospheric carbon amounts based on evidence from the past; according to Chris Measures, oceanography professor at the University of Hawaii, models that take the oceans into account “must include iron if they are to be at all realistic.” Last year, Measures spent 100 days at sea testing water for signals of aluminum and iron. In collaboration with Bill Landing of the University of Florida, he travels the oceans in search of trace metals derived from dust. As trace metal oceanographers, Measures and Landing have partnered with CLIVAR (climate variability)/CO2, a global project that seeks to understand why climate varies. CLIVAR/CO2’s oceanography project consists of research cruises that monitor changes to the basic properties of seawater. Trace metals are beyond the scope of “basic properties,” but Measures and Landing have received permission and funding to tag onto these cruises, which allows them to acquire data at the highest density yet.

On CLIVAR/CO2 cruise I8S, we see a surge in the fluorescence signal just off Antarctica, indicating more productivity. But why, in these iron-limited waters, is the productivity higher? Where is the iron from? Measures finds it unlikely that a mighty wind has deposited dust this far south. Instead, he posits that the iron is washing off the underwater continental shelf of Antarctica. As he suspects, a data map shows that there is more dissolved iron near the coast, and that levels of iron and productivity plummet as we enter the open ocean. With each sample of disintegrated dust, theories are constrained further until we are left with the truth.

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I8S Podcast: The CLIVAR Program and Location Sep 25, 2013

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By Pien Huang

One of the major improvements to the 4th report of the Intergovernmental Panel on Climate Change, is the use of better predictive models. In the six years since the publication of the third report, they’ve cleared up some uncertainty by scoring the performance of their models to real observations.

We’ll take you aboard the Roger Revelle, a research vessel of the Scripps Institution of Oceanography, to look at one of the first steps in climate change prediction – collecting real-time data on which models are based.

In the first of a four-part series, we’ll look one cruise, I8S, as part of a larger data collection program.

[waves; birds]

In February and March 2007, the R/V Roger Revelle spent six weeks sampling water from Antarctica to the west coast of Australia, under the direction of Captain David Murline and Chief Scientist James Swift. This transect is one of about sixteen that are monitored every ten years in the Climate Variability – CO2 Repeat Hydrography program, or CLIVAR for short.

CLIVAR was born out of the World Ocean Circulation Experiment, a one-time research project in the 1990’s that trolled the oceans and created a vertical profile of water properties throughout the oceans, such as temperature, density, and carbon and oxygen content. CLIVAR was developed to continue and to improve on the measurements of the World Ocean Circulation Experiment, to create an ongoing record of the oceans on a decadal scale. It is the start of a modern oceanographic record akin to the measurements taken by Charles Keeling, who put a sensor on a tower in Mauna Loa, and first alerted us to the rising levels of CO2 in the atmosphere in the early ’60’s.

Measuring the oceans is more involved. To do it right, you have to take a boat out, drop an array of bottles and sensors overboard, and haul them back up, processing water samples on-site. And then you repeat this, in our case, over 80 times. Each of these steps takes time, technology, and manpower, as well as a lot of money and planning. CLIVAR is an international program, and in the United States, it’s funded by the National Science Foundation and the National Oceanographic and Atmospheric Association (NOAA).

In the planning stages of CLIVAR, scientists at a convention took a beach-ball of the Earth, and drew in lines which they felt represented the world’s oceans. These lines have since been debated and pared down, but there is a randomness to their names. Chief Scientist Jim Swift, who was present at the meeting, has this to say:

Why, for instance, is this called 8South and 9N? There’s some – we’ll call it goofiness to the WOCE line numbers. I9 comes over here, and I9 south over her, I9N comes up here…it’s just scientists, you know, doing their thing.

All of these transects have a common purpose, but each individual cruise requires months of planning by the Chief Scientist, who tailors the trip to a particular region, and also accommodates add-on programs from other scientists. A day of shiptime on the Roger Revelle costs a minimum of $29,000. So whenever possible, the scientists collaborate to save on operational costs like shiptime, fuel, and labor.

What really sets I8S apart from other CLIVAR cruises is location. Because the transect starts in Antarctica, the trip departs from New Zealand and requires two weeks of travel time to its first sampling station. Chief Scientist Jim Swift discusses the planning:

So I got some historical ice information; well, there’s a lot of ice there in December, so December’s too early to start the cruise. But if I look at January, we’re getting a big reduction in the ice, and by February, that’s the ice minimum. And oh, by March, it’s starting to grow in again. So the sea ice minimum in this region was in approximately overall February, so I told the ship scheduling people that the ideal for us was to reach this point at the ice minimum in early February.

Our cruise track, if transcribed on the opposite side of the world, would start with a two week steam across the North Atlantic, from the coast of France to Hudson Bay, and then a sampling route that runs south, down through the Great Lakes to Alabama, and then out to Bermuda.

In early February, we left port in Dunedin, New Zealand on a southwestern course, our ship laden with food and lab equipment for the next six weeks. We plunged through the Roaring ‘40’s which are followed by the Roaring ‘50’s, latitude zones that are located in the only place in the world where there is infinite fetch. Fetch refers to the distance a wave can travel before it breaks; the further a wave has traveled, the more energy it has. The waves in the Roaring 40’s and 50’s are caught in the Antarctic Circumpolar Current, and can theoretically travel in a circle around Antarctica forever. The waves don’t break, but they produce colossal swells. Luckily, Captain Murline’s steady course keeps seasickness to a minimum, and cribbage tournaments keep us occupied through the worst of it. We are well-rewarded when we cross over the Circumpolar Current.

Josh Green reads from the blog of Joe Ferris, second-mate:

When you get so far south the wind dies down and the clouds part and you have beautiful days from the high pressure system that always sits over the continent. Also great long sunsets and sunrises. Getting here we haven’t seen the sun for two weeks, and lots of fog. [But] now [that] we are here and its amazing, we…turn around and starting working our way back north.

Along with the sun, the proximity to Antarctica brought icebergs in all shapes and sizes, from those you could net with a fishing net, to entire islands that dwarfed our ship. It was a treat for the passengers, but a strain on the crew.

Second mate Joe Ferris, whose responsibilities include navigating the night watch, writes:

Today rates as one of the most intense 4 hour watches of my 8 year career at Scripps Institution. While driving a north-westerly line…we again ran into the ice edge. From the satellite maps we knew to expect it somewhere in the vicinity…but the ice edge today was blown and dispersed seaward from southerly winds… we approached the ice edge trying to see how close we could get and looking for a safe spot for a station. There was none, small bergs were everywhere…[and] we spent a good three hours maneuvering around icebergs at close quarters to get out. Pretty spectacular stuff, except I really didn’t have much time to enjoy it since I was the one on the helm.

Still, manning the controls on the night watch has its perks:

Last night I was treated to a once in a lifetime display of Aurora Australis, otherwise known as the Southern Lights. We had a big storm all afternoon, but by midnight the sky cleared and off on the horizon a blank of clouds started glowing green. Suddenly the Aurora Australis developed into a wide band arcing and dancing across the entire sky. The bands were shifting between purple, pink, and green, and it all seemed so…close that it [felt like] we were in it…

I tried calling the labs but everyone was asleep, so I woke the chief scientist up and when he saw the show he called everyone else. Ten minutes later I had about 20 scientists on the bridge, they didnt see the best of show, but they got to view some bands develop and dance around for a hour before it completely died out.

For I8S Outreach, this is Pien Huang. Tune in next, when we explore the machines and robots of data collection, on-board I8S.

This broadcast has been supported by the National Science Foundation, the National Oceanographic and Atmospheric Association, and the Scripps Institution of Oceanography.

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