Strikingly stormy weather, science, and (a lack of) stratification

Here on Anvers Island, another stormy spring day is coming to a close. The weather system responsible for this morning’s gale came in from the north around 4 a.m., bringing wind gusts in excess of 50 knots and driving snow that had the feel of sand. The worst of the storm hit us right at 8 a.m. — the same time that Jeff and I had planned to hit the water to collect some samples for our research. We resigned ourselves to (mostly) indoor work for the day as we listened to the wind howl outside. This is what it looked like this morning on the boardwalk between the two main buildings here on station:

Given the other storms I’ve already written about this season (here and here), you might suppose the video clip is a re-post. (I assure you, the above is original footage from my trip to breakfast this morning.) As I wrote earlier this season, stretches of fair weather here on the Peninsula are really just breaks between an endless procession of low-pressure systems that circulate around the Southern Ocean, to our north.

Jeff and I are taking advantage of the “weather day” to catch up on some personal business and complete some lingering lab work from a successful on-water LTER sampling effort yesterday at stations B and E. (Yesterday’s outing was our first “two station” sampling of the season.)

At a basic level, we keep tabs on the weather for its impact on our ability to sample: Safety regulations here prohibit us from heading out onto the water when winds exceed 20 knots. But, the conditions so far this season — particularly the high winds we’ve been seeing — have also been a subject of considerable scientific interest for the members of team C-045/C-019 (see this past post for some introductions).

This has been a stormy past month here at Palmer. In the past 25 days, we’ve been swept over by six low pressure systems with sustained winds that exceeded tropical storm force — that is, greater than 34 knots. This morning’s storm (not on the plot below) makes seven such events:

A stormy spring: Wind speeds and peak gusts recorded at Palmer Station over the past 25 days.

A stormy spring: Wind speeds and peak gusts recorded at Palmer Station over the past 25 days.

I took a quick look at archived Palmer Station weather data from the past six years to get a sense of whether we’ve had an anomalously high number of storm events so far this year. I confined my search to the number of unique storm events with winds ≥ 40 knots, or 46 miles per hour. The data seem to suggest we aren’t crazy in thinking this spring has been worst than most in recent memory. Over the same 25-day period in the past six years, Palmer has borne the brunt of just eight or nine storm events with sustained winds ≥ 40 knots:

Wind speeds recorded at Palmer Station over the past six years, for the period Oct. 28 to Nov. 22. This is the same time interval as in the plot above. The record from each year (2009-2014) is plotted in a different color. Only eight or nine storms with winds ≥ 40 knots were observed in six years over this particular 25-day period.

Wind speeds recorded at Palmer Station over the past six years, for the period Oct. 28 to Nov. 22. This is the same time interval as in the plot above. The record from each year (2009-2014) is plotted in a different color. Only eight or nine storms with winds ≥ 40 knots were observed in six years over this particular 25-day period.

This year, we’ve had seven such events over the same 25-day period. The data I’ve introduced here aren’t conclusive, of course — but they do give the general sense that this spring has been a bit unusual. As Jeff points out, this is consistent with the current positive state of the Southern Annular Mode, or SAM. Jeff has explained quite a bit about the SAM — and its hypothesized influence on the climate and ecosystem of the West Antarctic Peninsula — here and here.

Among the many scientific reasons we — and almost all oceanographers, for one reason or another — are interested in the wind is its effect on the physical structure of the water column. In many locations in the ocean, seasonal or persistent stratification of the water column — that is, separation of less dense water at the surface of the ocean from deeper water that is less dense — is what sets the stage for algae or photosynthetic bacteria to bloom. (Wikipedia has a good definition of bloom, here; I was told my use of the term in a previous post might have been confusing to some non-oceanographers!) The strength and extent of surface wind largely determine how deeply the water column gets mixed; wind, therefore, represents a key constraint on stratification. In general, stronger, more frequent storms can prevent the water column from stratifying, while calm weather allows stratification to take hold.

Curious penguins and clear skies greeted us on Nov. 15 as we ventured out to our ice station in Arthur Harbor. Abnormally stormy weather has prevented the water column from stratifying, but still has not blown away all the sea ice to the north of Palmer Station. We hope to sample from the sea ice again in the next few days.

Curious penguins and clear skies greeted us on Nov. 15 as we ventured out to our ice station in Arthur Harbor. Abnormally stormy weather has prevented the water column from stratifying, but still has not blown away all the sea ice to the north of Palmer Station. We hope to sample from the sea ice again in the next few days.

A brief attempt to explain what I’m talking about:

Water density in the ocean is determined by salinity and temperature. If water at the surface of the ocean is allowed to heat up enough that it can become a distinct, separate layer “floating” atop the rest of the ocean, it can provide an incubator of sorts for the phytoplankton who are lucky enough to find themselves “stuck” there. If there are sufficient supplies of certain nutrients like phosphorus and nitrogen in this layer and there continues to be enough, phytoplankton living there can grow. When this growth is rapid, we call it a bloom.

We are waiting for things to set up like this in the waters adjacent to Palmer Station. We’ve been hoping to collect samples during a bloom here, both because we’re interested in tracking the bloom itself and because several experiments we have planned require water samples rich in algae.

The water at the surface of the ocean here doesn’t ever get “warm” by human standards, but it can heat to 5 or 6 degrees above the temperature of the rest of the water. This is more than enough to set the stage for growth.

To a certain extent, throwing a little wind into the picture isn’t a bad thing. Sure, it can temporarily break down the separation between this distinct surface later and the rest of the water below. If you’re one of the plankton unlucky enough to be driven down into the deeper ocean by the mixing of the wind during such an event, you’re likely done for. But, this mixing can bring critical nutrients up from the deep after concentrations have been depleted by all the plankton feasting in the warm surface water.

However, we’ve been wondering whether there’s been too much wind this season here at Palmer. Our hunch was that all this wind might be mixing the water too frequently and too severely, thus preventing the water column from stratifying to the extent necessary for a big bloom. Jeff decided to ask Nicole, our resident physical oceanographer, whether this could be true. (I introduced Nicole in an earlier post, here.) Sure enough, after some digging, Nicole reported that storms of the sort we’ve been seeing are capable of mixing and homogenizing the water all the way down to 50 meters. That’s 164 feet!

With a new storm every 4-5 days, it’s difficult to imagine the water will remain undisturbed for long enough for the necessary warming to take place.

An elephant seal blocked traffic on station on Nov. 15.

An elephant seal blocked traffic on station on Nov. 15.

That doesn’t mean there isn’t still lots of interesting biology and chemistry (and physics — sorry Nicole!) going on right now, but it means we’re not yet witnessing the even for which we have, in large part at least, been waiting. For my own project, I’ve been hoping to witness such a bloom coincide with the abnormally high doses of ultraviolet radiation we’ve been receiving here this spring. It could still very well happen in the next month, and I’ll be sure to report back when and if it does.

Meanwhile, the seals, penguins, and other birds we’ve had here on station this season do not seem to be preoccupied with the lack of stratification. Perhaps this seal’s choice of resting place, which put a halt to traffic here on station a few afternoons ago, was an expression of displeasure.

There were other some perplexing interspecies encounters here on station this past week. These Gentoo penguins (and one Adélie — see if you can spot it) took some time out of the water to conduct full, bumper-to-bumper inspection of a boat trailer and utility vehicle here by the boat ramp:

Not sure if we passed muster. The persistent presence of this group of penguins here on station over the past three weeks has me convinced that we’ll be receiving a follow-up visit in the very near future.

Lastly, Saturday, marked the 100th anniversary of the date on which Ernest Shackleton’s ship Endurance was finally crushed by the ice in which it had been beset for nearly a year. Jeff has some perspective here.

A few other images from the past 10 days on and around station:

Penguins on the sea ice in Arthur Harbor.

Penguins on the sea ice in Arthur Harbor.

IMG_3476IMG_3471

A scientific update, and (finally) some introductions

First, a scientific update: The start of Palmer Station “boating season” is imminent. Several strong storms this past week (video here) have blown away much of the sea ice to the south and west of station, leaving only the boats to be dug out of their snowbanks and the station’s boat ramp to be cleared of snow. This a herculean task, given the amount of winter precipitation the Peninsula received this year, but the staff here are working furiously to get the job done.

View from the Palmer Station pier at almost 10 p.m., November 11, 2015. Some of the fast ice in Hero Inlet has broken off into scattered floes. Icebergs are visible on the horizon.

View from the Palmer Station pier at almost 10 p.m., November 11, 2015. Some of the fast ice in Hero Inlet has broken off into scattered floes. Icebergs are visible on the horizon. To the right is the southern edge of the fast ice on which we’ve been sampling these past two weeks.

Fortunately, the relatively large expanse of fast ice on the other (north) side of the station — where we have been conducting our ice sampling — continues to hold itself together. Many of us were worried that the storms would blow out all the ice. Being that this didn’t happen, we’ll gladly take the current situation for as long as it lasts.

In fact, we took full advantage of the ice during a lull in the weather earlier this week. Using a special pump, we collected 120 liters (~ 32 gallons) of water on Tuesday for an experiment back on station. Over the next week or so, we will be using the water we collected to simulate — under very controlled conditions in one of the station’s open-air tanks  — the effect of the ice blowing out to sea. In many marine and aquatic ecosystems, the seasonal retreat of ice cover is a critical event: The phytoplankton and bacteria living in the darkness immediately underneath are suddenly exposed to more sunlight than they’ve seen in six months. This, of course, is often when a “bloom” of phytoplankton happens. (Another critical ingredient for bloom initiation is wind; Jeff has more here.)

Members of the B-045 and B-019 sampling team head out to the Arthur Harbor ice station on Nov. 10, 2015. While on station, we collected 120 liters of water for an on-deck experiment back at Palmer.

Members of the C-045 and C-019 sampling team head out to the Arthur Harbor ice station on Nov. 10, 2015. While on station, we collected 120 liters of water for an on-deck experiment back at Palmer.

Here at Palmer, we are controlling the amount of light that our samples are receiving in the on-deck tank to simulate the ice retreat. With any luck, the ice at our station will actually retreat within the next few weeks, and we’ll be able to compare the result of our experiment with what’s really happening in the environment. (In the environmental sciences, this kind of opportunity is less common than you might think!)

Introductions

But now, I’m finally coming through on a promise. Below, you will find introductions to members of the LTER scientific team currently conducting research at Palmer Station. There will be many more scientists onboard station this season working on their own projects; my decision to introduce only the LTER cast here is no slight to them.

Principal investigators

First, while none of them is currently present here on station, there are 10 principal investigators (“PIs” and “co-PIs”) who direct — and hold the funding for — the Palmer LTER study. I’ve included a brief note at the end of this post on the role of these PIs in obtaining funding for the science that goes on here at Palmer. These scientists come from various institutions and bring different sorts of expertise to the study. Some are experts in marine biology or ornithology. Others study the ice or sea currents, while still others use computer models to predict how the ecosystems of West Antarctica will change in the future.

Hugh Ducklow, a professor at Columbia University, is the LTER PI for whom I am officially working while here at Palmer. Hugh is a microbiologist and biogeochemist and is currently the lead scientist on the LTER study. Formally, he is responsible for the study’s Microbial Ecology and Biogeochemistry component. (Our sub-section of the LTER study has the U.S. Antarctic Program project number C-045, and this is how we usually refer to ourselves. Both scientists and support staff here on station often refer to the various research groups by project number, since it’s the easiest way to keep track of everyone.)

I got to know Hugh when he was director of the Ecosystems Center at the Marine Biological Laboratory in Woods Hole. Hugh is a mentor and member of my thesis committee. I would be remiss here in failing to also mention Hugh’s research technician, Naomi Shelton; Naomi is the logistician who keeps Hugh’s Palmer work going, and she continually provides us with very valuable guidance. While Naomi is not here on station at the moment, she spent time on station last season and is part of Hugh’s team on the annual LTER research cruise. Naomi previously worked at the Dauphin Island Sea Lab on the Gulf Coast in Alabama.

The other (present) members of team C-045

My primary field team partner this season is microbiologist Jeff Bowman, a postdoctoral fellow at the Lamont-Doherty Earth Observatory (part of Columbia University). Jeff, whom I introduced indirectly in a previous post, arrived here on station with me last month and will depart when I leave to head north in December. Jeff has studied the microbial communities (algae and bacteria)

Jeff tries on Tuesday to find our original hole in the ice so we could sample through it. We couldn't find it, so we had to drill a new one.

Jeff tries on Tuesday to find our original hole in the ice so we could sample through it. We couldn’t find it, so we had to drill a new one.

associated with sea ice in both the Arctic and in and around McMurdo Sound, on the other side of Antarctica. He has significant field experience at both ends of the earth, and is leading our burgeoning sea-ice sampling effort at Palmer this season. Jeff maintains a very well-written and scientifically-oriented blog at http://www.polarmicrobes.org; I’d recommend following the action there as well. Jeff earned his Ph.D. in biological oceanography from the School of Oceanography at the University of Washington. On station this season, he is filtering large volumes of water for analysis of DNA and RNA; this will allow him to assess both the genetic potential of the microbial community (i.e., what microbes are present and what they’re capable of) and “who” is doing what at any given time.

Later in the season, several additional personnel will be joining the C-045 effort here at Palmer Station. Joining us in mid-November will be Conor Sullivan, a recent Brown University graduate who was part of the Palmer field team last season, and Ribanna Dittrich, a graduate student at the University of Edinburgh in Scotland. Rachel Kaplan, another recent Brown grad, will be joining the team after Jeff and I depart.

Lastly, I want to introduce microbial geochemist Colleen Hansel, an associate scientist at Woods Hole Oceanographic Institution. Colleen had a short stay here at Palmer — she arrived with Jeff and me in October and then headed back north five days ago — but she managed to set us up with some critical, additional instrumentation that could add another fascinating dimension to the science here this season. Colleen left us with some special equipment to measure two kinds of reactive oxygen species (“ROS”) in the seawater we are collecting. For a short introduction to ROS and how they fit into my (and Colleen and Jeff’s) work, see these two paragraphs in my previous post.

Colleen has set us up to make measurements of two very elusive chemical compounds: Superoxide, and hydrogen peroxide. These compounds act as chemical signals and can degrade (or modify) other organic compounds that are nearby. Superoxide and hydrogen peroxide are strong oxidizing agents, meaning they can remove electrons from other nearby molecules; needless to say, this “stripping” of electrons is a powerful process that can have very negative effects. The tricky part is that neither of the two compounds sticks around for very long. In fact, most superoxide degrades in less than a minute! Colleen and members of her laboratory group have spent the last few years refining a working method to measure superoxide in the environment. This enabled them to make some of the first measurements showing that superoxide is produced not just by photosynthetic organisms like plankton, but also by bacteria.

We (mostly Jeff!) expect to consult frequently with Colleen over the course of the next month and a half.

Our close partners (and other scientists)

Members of B-019 and B-045 at the ice station in Arthur Harbor.

Members of “C-019” and “C-045” at the ice station in Arthur Harbor.

The members of C-045 work very closely at Palmer with members of Oscar Schofield‘s phytoplankton ecology and bio-optics group, who go by the project number C-019. Oscar is another PI on the LTER project. C-045 and C-019 share much of the sampling that goes on here every season via small boat, and the two groups are jointly participating in the current sea ice sampling effort. The team leader for C-019 right now is Nicole Couto, a graduate student at Rutgers University. This is Nicole’s fourth trip to Antarctica. (Nicole has a blog you can follow here, with some good posts about life and science at Palmer from her previous three seasons “on the ice.”)

Despite making measurements at Palmer of chlorophyll and other parameters associated with the life (and health) of phytoplankton, Nicole is actually a physical oceanographer who studies the effect that currents, sea ice formation, and other physical processes have on the phytoplankton community here. She uses very cool instruments called gliders to collect data for much of her work. Nicole is joined this season by a recent Rutgers graduate, Chelsea Farischon, and a rising Rutgers sophomore, Ashley Goncalves.

Also on station at the moment are Ben, Carrie, and Shawn — three birders who are members of the LTER study’s seabird component. The seabird (mostly penguin) effort is led by Bill and Donna Fraser. Bill and Donna have been studying the bird colonies around Palmer Station for more than 40 years. The startling decline over that time period in the size of the Adélie penguin colony on Torgersen Island was the inspiration for a book by Fen Montaigne that bears Fraser’s name. Ben, Carrie, and Shawn are among those here who have been anxiously awaiting the disappearance of the sea ice since they can only access many of the colonies they study using small boats.

Lastly, though they are not directly associated with the LTER study, two members of Rhian Waller‘s group from the University of Maine are here on station this spring. They are carrying out experiments in the aquarium here on a unique species of cold-water coral. On our trip south last month, the Gould retrieved over 100 of these corals from the ocean floor.

A short aside about LTER funding

An aside about funding for the LTER study, and the process that PIs (like Hugh) must go through to keep bringing in the necessary funding:  Like all taxpayer-funded science administered by the U.S. National Science Foundation, the Palmer LTER study is a research grant. All research grants awarded by the NSF (and most, but not all, other federal agencies) are based on scientific proposals that are vetted through a stringent peer review process. A key difference with the LTER program is the term of each grant: Instead of the two or three years of funding attached to a “normal” NSF research grant, grants for long-term research at the various LTER sites are made on a renewable six-year cycle. All of this means that LTER scientists are required to submit fewer (albeit much lengthier) proposals than those crafted for research elsewhere. The important point here is that they’re still required to submit themselves to the peer review process. There are some misconceptions in the U.S. research community that scientists associated with the various LTER projects get a “free pass” when it comes to the grant game. Proposals to fund work on LTER projects can (and do) fail: For example, the Shortgrass Steppe site, in Colorado, was de-funded by NSF in 2014 after the project’s PIs submitted an unsuccessful renewal proposal.

If you made it this far, thanks for reading — and maybe you learned something about the grant process.

Until next time,

Jamie

Anomalously high precipitation this winter means mountains of snow covering everything here on station... including the small boats! Jack (one of the marine technicians) is busy digging.

Anomalously high precipitation this winter means mountains of snow covering everything here on station… including the small boats! Jack (one of the marine technicians) is busy digging.

Grey skies greeted our sampling effort on Tuesday. This isn't a black and white photo!

Grey skies greeted our sampling effort on Tuesday. This isn’t a black and white photo!

When the ice is thick, sample through it

A Nov. 4, 2015, image from the MODIS Aqua satellite shows a tongue of ice extending toward the pole from Palmer's location at the southern tip of Anvers Island. (This was taken on a rare day of mostly clear skies; the wispy features in the image are clouds.)

A Nov. 4, 2015, image from the MODIS Aqua satellite shows a tongue of ice extending toward the pole from Palmer’s location at the southern tip of Anvers Island. (The image was taken on a rare day with minimal cloud cover; still, some of the wispy features in the image are clouds.)

Sea ice, some of it more than a meter (~ 3.3 ft) thick, continues to linger in and around Arthur Harbor.

In many years, persistent sea ice is a significant source of frustration to early-season scientists at Palmer: Conditions like we’re seeing now generally preclude access via small boat to the regular Palmer LTER sampling locations at stations “B” and “E.” (View a description of the two stations in an older post.)

This season, however, the sea ice — which supports unique microbial communities at the base of many Antarctic food webs — is serving as an object of science rather than an obstacle. While we await the right combination of wind and warmer temperatures to blow the ice out to sea, the scientists of Palmer LTER’s Microbial Ecology and Biogeochemistry and Phytoplankton and Bio-optics components are sampling through the ice to characterize the frigid waters below.

Polar microbiologist Jeff Bowman (who maintains his own blog here) uses an ice corer to establish a bore hole through the sea ice near Palmer Station, as Nicole Couto (a graduate student at Rutgers University) and members of Palmer's Glacier Search and Rescue Team, provide needed support and encouragement.

Polar microbiologist Jeff Bowman of Columbia University’s Lamont-Doherty Earth Observatory uses a corer to establish a bore hole two days ago through the sea ice near Palmer Station, which is visible in the distance. (Jeff maintains his own blog here with some superb photos and excellent, more extensive scientific background on some of the measurements we’re making this season.) Nicole Couto, a graduate student at Rutgers University (in white hat), and members of Palmer’s Glacier Search and Rescue Team, provide needed support and encouragement. Coring is tough work!

It turns out that most of what we know about ice-attached and under-ice microbial communities in polar regions comes from (1) various locations in the Arctic and (2) studies in and around McMurdo Sound. (McMurdo, site of the largest U.S. research station in Antarctica, is 3,800 km, or 2,370 miles, from Palmer Station — on opposite side of the continent!)

The relative lack of information about sea ice microbial communities in West Antarctica makes it difficult to say how they will be affected by the very rapid shifts in climate currently underway here (see, for example, work by Bromwich et al. and Meredith and King). There have been some studies on sea ice West Antarctica, but the literature is not extensive. (A group of scientists at NASA generated some controversy recently with an analysis that found the overall mass of Antarctic sea ice is growing, despite global warming; in that study, however, the authors found that sea ice on the West Antarctic Peninsula was still very much losing mass.)

Jeff heaves around on the corer. We measured the ice thickness at our station at 66 cm (26 inches). The snow on top was 35.5 cm (about a foot) deep. A unique feature of first-year ("young") Antarctic sea ice is its low density; because the salty, young ice hasn't had time to compact yet, it is full of air bubbles and cavities that decrease its density., the ice is less dense than hard second year-ice Oceansome of the ice actually ends u

Jeff heaves around on the corer. We measured the ice thickness at our station at 66 cm (26 inches). The snow on top was a very dense 35.5 cm (about a foot). Two unique features of the first-year (“young”) sea ice typical of Antarctica are its saltiness and the thickness of snow on top of it. The sea ice surrounding Antarctica (not the same as an ice shelf) tends to melt and re-form every year. Because brine (concentrated, salty water) does not get fully “squeezed” out of sea ice until it has been around for a few years, the sea ice down here tends to be salty (we tasted the core from our station to verify). Second, the weight of the all the snow we get here (the WAP is a very “wet” place compared to the rest of Antarctica) tends to push part of the ice down below the surface of the actual ocean! At our station, for example, the height of the sea surface was actually 7.6 cm above the top of the ice. Don’t worry — we didn’t get wet; all this really means in practice is that the first few cm of snow directly above the ice are slushy.

This uncertainty made us even more excited about the opportunity to sample from the ice here at Palmer. On Tuesday, we established a sampling station in the middle of Arthur Harbor, just off Palmer Station. We revisited the site the following day (on Wednesday) to make the first in what we hope will be a series of measurements. We collected samples and made measurements at two depths: Just below the underside of the ice (at around 1 m from the ice surface), and then at 3 m.

Sampling the ice

From both of these depths, we collected water for some basic, recurring measurements that form the basis for the LTER study. These parameters include particulate chlorophyll a, dissolved organic carbon, particulate organic carbon, bacterial and phytoplankton cell size and community composition, rates of primary and bacterial production, oxygen-18 (an isotope of oxygen), and basic macronutrients (nitrate and phosphate). We also made a profile of photosynthetically active radiation (PAR), the specific wavelengths of light that phytoplankton need to carry out photosynthesis. My field team partner Jeff has a great description of the importance of each of these on his blog.

In addition, we collected water for several special projects:

First, Jeff collected material onto several filters for DNA and RNA analysis, which will form the basis of his research here this season.

Second, Colleen Hansel, a scientist at  Woods Hole Oceanographic Institution, used some of the water to measure concentrations of hydrogen peroxide generated by the microbes living under the ice. (Colleen is happens to be a member of my Ph.D. thesis committee at WHOI.) She is an expert in the measurement and environmental function of certain reactive oxygen species (“ROS”), including hydrogen peroxide and superoxide.

Measurements at our ice station of photosynthetically active radiation (PAR), the light that plants use for photosynthesis. The light intensities are plotted as percentage of the light hitting the surface of the snow above the ice. Note that the scale on the x-axis is logarithmic, meaning there's a huge range in the data. Basic point: It gets really, really dark once you move directly away from the underside of the ice. You can blame all the snow! (Data from Nov. 4, 2015.)

Measurements at our ice station of photosynthetically active radiation (PAR), the light that plants use for photosynthesis. The light intensities are plotted as percentage of the light hitting the surface of the snow above the ice. Note that the scale on the x-axis is logarithmic, meaning there’s a huge range in the data. Basic point: It gets really, really dark once you move directly away from the underside of the ice. You can blame all the snow! (Data from Nov. 4, 2015.)

Third, I brought large volumes of water back to station, where I filtered it to collect biomass (organic material from bacteria and phytoplankton) for lipidomics analysis as part of my Ph.D. research. Lipidomics is a fancy word for the analysis of large quantities of lipid data (lipidomics is the lipid equivalent of genomics or metabolomics). It turns out that the molecules Colleen studies (and in which Jeff is interested) belong to the same overall class of oxygen-containing molecules produced as a result of many environmental stressors in the ocean. (See also a separate and very lengthy Wikipedia entry that addresses the production of ROS in marine microbes, here.) I am interested in two other kinds of ROS (specifically, chemical compounds called hydroxyl radical and singlet oxygen) because these compounds are what cause much of the “direct” damage to the lipids of marine microbes when they are subjected to the stress of ultraviolet radiation. When these ROS compounds react with lipids, they can cause the lipids to break apart into smaller fragments. Some of these lipid fragments are the sorts of “infochemical” compounds that are the object of my research (and much of the research going on in my lab right now).

Very early impressions

It’s too early to say what the lipid data will tell us (I will analyze the samples back in my lab in Woods Hole). But, it’s interesting to note that Colleen did measure modest quantities of hydrogen peroxide in the water samples we brought back from the ice station. In fact, the concentration was much higher just on the underside of the ice than it was at 3 m depth; this makes sense since algae produce hydrogen peroxide as a byproduct of photosynthesis, and photosynthesis depends largely on light (see plot to right). We also measured more bacteria in samples from just underneath the ice — though the rates of bacterial production, essentially a measure of how active the bacteria are, did not differ between the two depths.

Brown color is very evident on rotting ice floes in Arthur Harbor at the onset of the algal bloom two years ago, indicating the presence of large numbers of ice-attached algae.

Brown color is very evident on rotting ice floes in Arthur Harbor at the onset of the algal bloom two years ago, indicating the presence of large numbers of ice-attached algae.

All in all, however, things were pretty subdued from a microbial perspective: The core that came out of the hole didn’t have much brown or green color, which would serve as first-order visual evidence of an impending algal bloom. Things will start cranking soon, though (see photo from last season).

Science summary: LTER science is well underway down here at Palmer Station, but there’s no evidence yet of an algal bloom. Although I promised I’d formally introduce the members of our field team (Jeff, Colleen, Nicole, Ashley, and Chelsea), I’m going to hold off until next time. I’ve already indirectly introduced you in this post to Jeff, Colleen, and Nicole.

A feathered observer, and some other images

On a final note, I can say our work this week drew the interest of at least one (feathered) member of the Palmer community. After giving our efforts at the ice station a thorough inspection, this lone Adélie penguin (see below) followed us nearly all the way back onto land. No word yet on whether we passed whatever evaluation he or she was conducting.

The Adélie follows us back to station. Photo courtesy of station manager Rebecca Shoop.

The Adélie follows us back to station. Photo courtesy of station manager Rebecca Shoop.

FYI.

FYI.

Our Arthur Harbor ice station as viewed from the Palmer pump house.

Our Arthur Harbor ice station as viewed from the Palmer pump house.

I measure the thickness of the sea ice at a test hole on the way out to our station, as Mark and Nandi (members of the Glacier Search & Rescue Team) and Nicole look on. (We didn’t use the power auger to core the hole at our station because we wanted to minimize disturbance on the microbial community living there.) Photo courtesy Jeff Bowman.

Beginning of a new season

Hello from Palmer Station!

Our arrival at Palmer Station on Oct. 29 brought calm and mostly sunny weather.

Our arrival at Palmer Station on Oct. 29 brought calm and mostly sunny weather.

Living and working in the comparatively mild climate of the West Antarctic Peninsula, one sometimes forgets just how harsh this continent can be. Case in point: This afternoon’s weather.

The Laurence M. Gould departed on Oct. 31 after leaving the early season scientists (and cargo) at Palmer Station.

The Laurence M. Gould departed on Oct. 31 after leaving early season scientists (and cargo) at Palmer Station.

In the four days since the Laurence M. Gould dropped us off here, we’ve enjoyed fair conditions: While we received some significant snowfall overnight, the days have been dominated by mostly sunny skies and winds less than 20 knots (1 knot = 1.15 miles per hour).

This allowed those of us who had just arrived to move into our new accommodations on station, and afforded the ship’s crew ample opportunity to offload food and cargo. Since the Gould departed, those of us who disembarked — 15 scientists and one support staff member — have spent the past few days attending various orientations and (re)acquainting ourselves with the base. Many of the scientists also used the weekend to begin experiments or simply set up the laboratories where we’ll work for the next few months.

A storm off the Bellingshausen Sea brought 50 knot winds to station after several days of beautiful weather.

A storm off the Bellingshausen Sea brought 50 knot winds to station after several days of beautiful weather.

But the weather changed this afternoon in less than an hour. A storm coming in off the Bellingshausen Sea brought 50 knot winds and driving snow to Arthur Harbor, an abrupt reminder that we are setting into temporary lives on a thin peninsula that juts many hundreds of miles into the Southern Ocean.

Whereas the storms and severe winds that characterize interior Antarctica are controlled largely by continental weather patterns, weather on the WAP — that’s West Antarctic Peninsula — is largely defined by a series of low pressure systems that dance endlessly around the Southern Ocean. Periods of fair weather are simply the breaks between lows. While the Peninsula itself has some relatively large mountains, there is no significant land to the west of the station to impede the onset of these systems. (See Google Earth image at the bottom of the post.) This is an oversimplification, of course, but it helps to explain how the weather here can go from fair to fierce in no time flat.

As far as science goes: While ice conditions are not nearly as severe as they were two years ago, there’s nevertheless enough ice in Hero Inlet (chart of the local area here) to keep us off the water for the time being. In the meantime, we’re hoping to get out onto the remaining sheet of fast sea ice (“fast” means the ice is attached to shore) to sample the waters underneath.

In my next post, I’ll introduce the members of the scientific team from Columbia University, Woods Hole Oceanographic Institution, and Rutgers University, with whom I’ll be working most closely over the next few months.

Stay warm,

Jamie

Palmer Station is at the tip of the red arrow.

Palmer Station is at the tip of the red arrow.

Southbound (again) for science

A (warm) welcome back

Greetings, all!

It has been roughly a year and a half since my last posting in this space. After completing a successful field season at Palmer Station and aboard the ARSV Laurence M. Gould in the austral summer of 2013-2014, I’ve spent the past 19 months back in Woods Hole, Massachusetts, in my home laboratory at Woods Hole Oceanographic Institution. (You can check out some posts from the 2013-2014 field season using the “Archives” link on the main page of the blog…)

Right now, I am aboard the ARSV Gould in Punta Arenas, Chile, awaiting the roughly 9-day trip that will take me back down to Palmer Station until the end of December. The ship’s crew and scientific support staff are working feverishly right now to prepare the Gould for the transit: Food stores and equipment are being onloaded, navigation instruments and the ship’s engines are receiving necessary maintenance, and scientists and staff are moving into their temporary homes aboard the vessel.

No (reliable) word yet on what the weather will be like when we depart and cross the Drake Passage — the notoriously stormy body of water that separates the southern tip of South America from Antarctica.

I’ll be posting on the blog again over the course of my stay at Palmer, and I hope you’ll join me on the adventure. The subjects of my posts varied widely when I was on station two years ago, and I hope to maintain the same breadth of theme this time around. If you have a specific question about science or life on station, please e-mail me, and I’ll do my best to answer in my next post.

You can also subscribe to receive each post by e-mail: Just enter your email address in the field on the right side of the home page.

What I’ve been up to, scientifically

During my time back home, I was working primarily to refine and develop the methods and techniques I will need to complete my dissertation project sometime next year. I am investigating a group of chemicals that marine algae — the ocean’s single-celled plants — use as signals to “talk” to each other about the various sources of stress in their environment. (“Investigating” is a word we use in science for “researching.”) My scientific collaborators and I are specifically interested in oxidative stress — an inescapable and nearly ubiquitous feature of life in a universe composed of atoms and electrons.

In algae, it turns out, lots of things can induce oxidative stress:

  • Photosynthesis, the fundamental means by which plants convert solar energy, water, and carbon dioxide into organic matter and oxygen
  • Predation (i.e., getting eaten, or even the threat of getting eaten, by microscopic grazing animals such as zooplankton)
  • The basic process of respiration, the means by which nearly all organisms break down stored organic matter (“food”) for energy
  • Nutrient stress
  • And, a host of other processes

Another source of oxidative stress that comes from outside the cell itself is ultraviolet radiation. This is what brought me (and is bringing me back) to Antarctica. As a result of anthropogenic (human-caused) thinning of the stratospheric ozone layer, Antarctica receives very high doses of UV radiation in the Southern Hemisphere spring. You can check out the current UV conditions at Palmer and the other U.S. stations in the Antarctic at http://www.esrl.noaa.gov/gmd/grad/antuv/

I am interested in whether we can see the effect of this source of stress on the structural molecules (lipids) that make up the cell membranes of the algae that inhabit the ocean in and around Palmer Station. (Previous research has shown in a somewhat nonspecific way that UV radiation can induce high levels of oxidative stress in diatoms, a type of algae.) Cell membranes can break down as a result of this stress, producing small molecules which algae (and terrestrial plants) use as signals. These smaller molecules can be use as “biomarkers,” a term used in human biomedicine and in geochemistry for molecules that serve as indicators of a certain environmental process.

I’ll be posting later in the season withe some specific examples of how these small “infochemical” molecules function in the environment. And I’ll be explaining in much more detail about what my collaborators and I are doing to identify potential biomarkers of oxidative stress in the ocean.

That’s all for now — looking forward to having you along this season for the ride.

Jamie

With sea ice in full retreat, a start to sampling

While it prevented LTER scientists from getting into the field until mid-December, the persistent sea ice was no obstacle for an elephant seal that climbed up onto the rocks surrounding the station on Dec. 12.

Charismatic megafauna: Indisputably charismatic. While the persistent sea ice prevented LTER scientists from getting on the water until mid-December, it was no obstacle for an elephant seal who climbed up onto the rocks surrounding the station on Dec. 12.

After a long and inexcusable absence from this space, greetings again from 64º south. Some milestones have passed since my last update on Nov. 18. We’ve celebrated Thanksgiving, Christmas, and Hanukkah, each with good cheer and sustenance worthy of the best holiday gatherings stateside. For those USAP veterans who call this remote place home, the celebrations were that much more meaningful.

Christmas Day saw the scheduled arrival in Arthur Harbor of at least two Minke whales. Station lore holds that the season’s first whales always show up on Christmas Day; after fulfilling their contractual obligation with a brief show of breaching and splashing, this year’s travelers quickly moved on in search of food.

Sunset from atop the glacier on Dec. 21. The solstice brought just 135 minutes of official nightfall to Palmer Station.

Sunset from atop the glacier on Dec. 21. The solstice brought just 135 minutes of official nightfall to Palmer Station.

On Dec. 21, the Summer Solstice brought Palmer its longest day of the year. Just 135 minutes of official nightfall separated sunset, which occurred shortly after midnight, from the sun’s appearance on the horizon again at 2:22 a.m. Something between dawn and twilight persisted in the intervening hours — more than enough light for skiing up on the glacier or for a midnight walk through the moraine and glacial outwash that litters the station’s backyard.

A Nov. 30 image from the RadarSat-2 satellite showed the extent of the sea ice that lingered for months to the south and west of Anvers Island. In this false-color image, sea ice is white, while land masses and terrestrial ice have a blueish tint.

A Nov. 30 image from the RadarSat-2 satellite showed the extent of the sea ice that lingered for months to the south and west of Anvers Island. In this false-color image, sea ice is white, while land masses and terrestrial ice have a blueish tint. Station scientists and ship personnel use these images for scientific planning and navigational awareness.

And, for the scientists of the Palmer LTER study, the holidays ushered in another highly-anticipated event: The retreat of an anomalously persistent cover of sea ice to the south and west of Anvers Island,  which had prevented us from sampling for nearly three months. After a few days of favorable winds (see my earlier post, here), the morning of Dec. 27 finally brought the open water that allows us to collect samples for the first time at both of the study’s offshore sampling stations.

The stations — “B” and “E” — are two of the roughly 20 predesignated scientific sampling locations that dot the waters adjacent to Palmer Station. The LTER study collects samples at these two particular stations because they are ecosystem endmembers; samples from the two locations capture the major elements that shape the unique marine ecosystem surrounding Anvers Island. (The term endmember was originally used in geology and geochemistry to describe a mineral or rock representing one end of a series having a range of composition; today, biogeochemists and other earth scientists use the term to describe the two or more extremes of any system that can be characterized by mixing of elements with distinct properties.)

Samples collected at Station E capture the direct influence on the ecosystem of the Southern Ocean and Amundsen Sea. Station E is roughly 3 miles from shore, seaward of the small rocky islands that surround Palmer Station. The water depth at Station E is somewhere around 120 meters, and the salinity of the water is nearly 35, that of average ocean water.

In comparison, Station B is less than a half-mile from the nearest point of land, and fresh glacial meltwater typically lowers the salinity there to around 32 or 33. In the spring, runoff from nearby penguin colonies can increase the concentration at Station B of certain dissolved nutrients. And, “B” is shallower, with a depth of about 60 meters.

Antarctic sea ice extent in 2013 (bottom) and in 2011 (top). Relative to the trend established in the past 30 years, the 2013 sea ice cover on the West Antarctic Peninsula was anomalously extensive. The orange line shows the median ice extent surrounding the continent over the past few decades. While the extent and duration of the sea ice cover on the Peninsula has decreased dramatically over the past few decades, ice surrounding the continent as a whole has increased slightly.

Antarctic sea ice extent in 2013 (bottom) and in 2011 (top). Relative to the past 30 years, 2013 sea ice cover on the West Antarctic Peninsula was anomalously extensive. The orange line shows the median ice extent surrounding the continent over the past few decades. While the extent and duration of sea ice cover on the Peninsula has decreased dramatically over the past few decades, ice surrounding the continent as a whole has increased slightly.

At each site, we apply the bread-and-butter techniques of modern oceanography, combining the collection water samples from several depths in the water column with profiles of temperature, salinity, and the water’s optical properties using electronic instruments. By measuring certain properties of the water collected at the different depths, we can compare the two distinct but often overlapping populations of microbes that make their living at the two stations.

We divide up the water we collect for dozens of different types of analysis. On a normal day, for example, we set aside some of the water to measure the different pigments produced by the various algae at the two sites, chlorophyll being just one of many pigments used in photosynthesis. Another subsample is used to determine  the concentration in the water of dissolved organic carbon, or DOC, the billions of dissolved organic compounds that are suspended in every milliliter of seawater.

I had hoped to begin writing about the LTER sampling effort in late October or early November, the time when LTER sampling crews have traditionally begun their work in years past. But as I’ve described in this space throughout the spring, the uncharacteristic lateness of this year’s sea ice retreat — and the anomalously broad extent of the ice pack along the Peninsula for much of the winter — prevented us from conducting any real sampling.

It turns out this anomalous year has been as frustrating for us in the field as it has been a source of keen scientific interest among the many scientists back in the U.S. who conduct field work at Palmer Station.

Climatically, this year is a certain anomaly: West Antarctica, and the Peninsula in particular, remain among the fastest winter-warming locations on earth. (See, for example, a plot in this earlier post showing the dramatic decline over the past few decades in annual sea ice cover.) For whatever reason — the cause will be a source of scientific inquiry and debate over the next few years — the 2013 sea ice retreat defied the trend.

Austin Melillo, a geology student at Rutgers University, helps deploy the LTER CTD (conductivity, temperature, and depth) package amid sea ice at Station B.

Science, finally underway. Austin Melillo, a geology student at Rutgers University, helps deploy the LTER CTD (conductivity, temperature, and depth) package amid sea ice at Station B.

From the dining room here at Palmer Station, taking in the frozen sea day after day for nearly three months, I found it difficult to remember this was still a region of intense climatic change. Trends and anomalies in climate do not lend themselves to the standards and measures of human lives. We think on the timescales of months and seasons, comparing this year to the last and the next year to this one. Our human memories are short, and changes in climate occur over time intervals that often defy our comprehension.

As a scientist, I try to remember this. And I remind myself that the data we collect over the next few months as part of the LTER study may help to elucidate the causes and effects of the massive changes here in West Antarctica. Rationally, I know this year was an exception to an alarming trend. And yet, like all scientists, I am certainly human: It was difficult to look out at all the ice — more than anyone had seen in twenty years, yet an amount that used to be normal here 50 years ago — and remember that I was staring at an anomaly.

More to come from Palmer Station and the Laurence M. Gould. In the meantime, a few more images from the past month on station:

IMG_1353

Exceptionally calm water and remnants of the sea ice pack greeted us on our first trip to Station E.

IMG_1395

A leopard seal hauled out on an ice floe.

A leopard seal hauled out on an ice floe.

An enormous iceberg lingered just a few hundred yards from Station E as we collected water samples on Dec. 27.

This enormous iceberg lingered just a few hundred yards from Station E as we collected water samples on Dec. 27.

Bedfellows on a frozen continent: Science and the U.S. sea services

A ship's plaque bearing the coat of arms of the Coast Guard Cutter Glacier commemorates one of many visits by the icebreaker to Palmer Station during the 1970s and 1980s.

A ship’s plaque bearing the coat of arms of the Coast Guard Cutter Glacier commemorates one of many visits by the icebreaker to Palmer Station during the 1970s and 1980s. The plaque hangs in the station lounge with many others.

The nautical mementos that ring the walls of the Palmer Station lounge attest to a once robust partnership between Antarctic science and the U.S. sea services. A fading Coast Guard ensign bears the names of crewmembers who ventured ashore in 1984 from the now-decommissioned Coast Guard Cutter Polar Sea. A ship’s plaque embossed with the coat of arms of the Coast Guard Cutter Glacier proudly commemorates one of the icebreaker’s many visits to Arthur Harbor in the 1970s and 1980s. (On the seal, Glacier sails in the foreground as a penguin on an ice floe holds a banner bearing the ship’s motto — “Follow Me” — in its beak.) And a yellowing photograph of the CGC Polar Star, the only American heavy icebreaker still in operation and sister ship to the decommissioned Polar Sea, hangs on the opposite wall.

A small boat crew from the Coast Guard Cutter Polar Sea left this Coast Guard ensign during a visit in 1984. The leaving during a port call of a ship's plaque or other memento is in keeping with old nautical tradition.

A small boat crew from the Coast Guard Cutter Polar Sea left this Coast Guard ensign at Palmer during a visit in 1984. The “gifting” during a port call of a ship’s plaque or other memento is a nautical tradition.

These objects speak not just of the individual ships on which they arrived and of the crewmembers who left them, but of the U.S. sea services’ historical support of exploration and scientific discovery in Antarctica. Palmer Station, for example, owes its very existence to two Coast Guard cutters and a team of Navy Seabees.

To observe Veterans Day aboard Palmer Station in 2013 — as roughly 40 men and women did last week — is to both remember and celebrate the services’ past efforts here and to reflect on the much-diminished role that sailors and Coast Guardsmen play in Antarctica today.

In many ways, the military is no longer needed in Antarctica to the extent that it once was: Scientists, and the American taxpayers who fund the majority of those scientists’ research here, are served incredibly well by a capable contractor who manages the various stations and associated logistics. And the U.S. military does continue to provide some critical support for science on the Frozen Continent: The U.S. Air Force and New York Air National Guard now provide almost all airlift support for both McMurdo Station and the South Pole, for example.

But the fact remains: The end of the Cold War, combined with a lack of willingness in Congress to spend many millions of tax dollars on new icebreakers, has reduced the sea services’ financial and logistical investment in Antarctic science to a fraction of its former strength. While the decline of this vigorous partnership is a story worthy of books many times the length of this post, I have nevertheless endeavored to tell a bit of it here.

One thing is certain: The few men and women of the sea services who continue to stand the watch in the Antarctic today can take comfort in the fact that their duty is rooted in a long and storied history.

The Coast Guard Cutter Westwind at anchor in Arthur Harbor in winter 1967, after arriving on January 8 with a team of Navy Seabees. After transferring the team and several tons of gear ashore, the Westwind stayed on station as construction began on Palmer Station. Photo from the Palmer Station history pages at palmerstation.com.

The Coast Guard Cutter Westwind at anchor in Arthur Harbor in winter 1967, after arriving on January 8 with a team of Navy Seabees. After transferring the team and several tons of gear ashore, the Westwind stayed on station as construction began on Palmer Station. National Science Foundation photo by W. Austin, from May/June 1967 edition of the Antarctic Journal, via the Palmer Station history pages at palmerstation.com.

From the beginning, the U.S. sea services — the Navy and later, too, the Coast Guard — figured prominently in the history of American exploration and scientific discovery on the Frozen Continent. Many of the earliest American explorers to sail upon the Southern Ocean or travel across Antarctica were Naval officers: Men like Charles Wilkes and Richard E. Byrd earned themselves revered places in the annals of U.S. exploring history alongside civilian mariners like Nathaniel Palmer.

Navy Seabees from

Using special “jet set” explosives, Navy Seabees from Naval Mobile Construction Battalion 6 conduct underwater blasting in January 1967 to excavate a trench for Palmer Station’s seawater intake. Official Coast Guard photo from the Antarctic Journal, via the Palmer Station history pages at palmerstation.com.

While the terms of the Antarctic Treaty prohibit “any measures of a military nature” south of 60°S latitude, the treaty does “not prevent the use of military personnel or equipment for scientific research or for any other peaceful purpose.” It is under this second clause that the U.S. Navy and Coast Guard — and, today, the U.S. Air Force — have supported various U.S. scientific operations here.

The current McMurdo Station, the largest research facility in Antarctica and the logistics hub for most U.S. operations on the continent, was originally called Naval Air Facility McMurdo upon its establishment in 1956. (Long before the U.S. established its permanent presence at McMurdo, the British had occupied the site through the efforts of explorers James Clark Ross and, later, Robert Falcon Scott, both of whom were British naval officers.) And it was the Seabees of Naval Mobile Construction Battalion 6, with support from the USS Edisto and Coast Guard icebreakers Eastwind and Westwind, who constructed the first buildings and pier for Palmer Station in the late 1960s.

One need not read far into the first official Palmer Station operations report (full version of the document here) to understand how critical the Navy and Coast Guard support had been:

Pal_67report_acknowledgments

An except from the first official Palmer Station operations report, dated June 20, 1967. Link to the full report here.

The remainder of the 48-page report, and subsequent annual reports like it through the late 1980s, note the critical services the Navy and Coast Guard provided at Palmer Station with the U.S. icebreaker fleet. The Wind-class icebreakers, Glacier, and later the Polar Star and Polar Sea, were Palmer’s link to the rest of the world, serving as platforms for research at sea in addition to fulfilling resupply, construction, and personnel transport missions.

In the 1970s and 1980s, management, operation, and, finally, the resupply of Palmer Station by sea were gradually civilianized: The military personnel assigned to Palmer were replaced by civilian government contractors and Coast Guard icebreakers were supplanted by ice-strengthened civilian research vessels. (For at least a few years, a Navy corpsman continued to provide overwinter medical services at Palmer, even after the rest of the former Navy positions had been civilianized.)

The Polar Star and Polar Sea continued to provide icebreaking and resupply support at McMurdo until the mid-2000s, when an increasing number of equipment failures aboard the two aging cutters began to render them increasingly unreliable. Beginning in 2006-2007, the National Science Foundation began contracting a series of foreign icebreakers (the Swedish Oden and then the Russian Vladimir Ignatyuk) to perform the critical resupply escort mission. In 2011, when Sweden pulled its support of the Oden on short notice, the U.S. nearly missed the short window of good weather necessary to deliver critical fuel and supplies to McMurdo.

Today, the U.S. icebreaker fleet stands at its smallest size in nearly 75 years. (An office at Coast Guard Headquarters maintains this nation-by-nation chart of the world’s heavy icebreakers.) Only the Polar Star, which just completed a $90 million retrofit that will keep it in service for another decade, is capable of breaking ice into McMurdo Station.

Without the necessary support in Congress, the Coast Guard currently has no firm plans to begin building any new ships to replace it. (The Coast Guard’s only other polar icebreaker, the 420-foot Coast Guard Cutter Healy, is a lighter-duty ship designed primarily for scientific support in Arctic waters. And, while highly capable, the two Antarctic research vessels the National Science Foundation currently contracts from Edison Chouest Offshore are only ice-strengthened. This means the two ships, the Laurence M. Gould and Nathaniel B. Palmer, are not equipped to break even half of the 21 feet of ice thickness the Polar Star can handle.)

For five scientists and support personnel who were scheduled to leave Palmer Station last week aboard the Gould, the state of the U.S. icebreaker fleet became an issue of personal concern: Due to the persistent sea ice in the waters south and west of Anvers Island, the Gould was unable to get to the station to transfer inbound supplies or pick up the outbound passengers. This isn’t, of course, a matter of life or death: The station keeps plenty of extra food and fuel on hand for situations like this one. But the delay represents a very significant inconvenience for the unlucky few who were scheduled to head north.

Circumstances like the one in which these men and women found themselves are, to be sure, a normal cost of conducting research in this harsh place. But they are also the consequence of a decades-long shift in the way science is supported here. The current arrangement is precarious, yet financially advantageous for taxpayers. Scientists, too, have not generally suffered: Research funded by the U.S. Antarctic Program generates an incredible number of new scientific findings each year.

To observe Veterans Day at the end of the world is to be grateful for the service of the sailors, airmen, and Coast Guardsmen whose efforts over more than a century have allowed U.S. science to come this far. But it is also to wonder: Might a new U.S. icebreaker — and with it, the ability to access those parts of the Southern Ocean currently inaccessible — allow us to make even greater discoveries?

While ice lingers on the sea, science keeps rolling in the air above

Twilight now persists at 64° south long after the sun has dropped below the horizon, providing ample light for a hike up and over the glacier. While sea ice on the Bismarck Strait keeps science temporarily at bay, the jagged peaks of Anvers Island’s Trojan Range show their snowy faces after several weeks of cloudy weather. Time of photo: 10:48 p.m. local time.

Greetings again from 64° south.

As I write, persistent sea ice continues to stand between most of Palmer’s scientists and their objects of study. For access to the water and the islands around the station, scientists here rely on a small fleet of Zodiac inflatable small boats. Sturdy and versatile, Palmer’s black Zodiacs are very similar to craft the Navy uses to deliver its SEAL teams to hostile shores the world over. And yet, as I’ve learned over these past three weeks, no inflatable boat can contend with the foot and a half of refrozen brash ice that currently chokes the inlet here.

Without open water, LTER scientists studying the bacteria and phytoplankton in the sea around the station can’t even get get out to nearby stations “B” or “E” to collect water samples. (There are 20 or so predesignated LTER sampling locations around Arthur Harbor; I’ve posted a chart here.) And things aren’t much better for Palmer’s recently-arrived team of penguin researchers: Most of the penguin colonies Bil Fraser and his team have been studying for the past four decades or so are on islands even further offshore.

Greg Roberts poses in Palmer's "backyard" with PAEROS, the Portable Aerosol Observing System. Roberts and Craig Corrigan, atmospheric scientists from  the Scripps Institution of Oceanography, developed the autonomous instrument package to measure aerosol particles in the surface atmosphere.

Greg Roberts poses in Palmer’s “back yard” with PAEROS, the Portable Aerosol Observing System. Roberts and Craig Corrigan, atmospheric scientists from the Scripps Institution of Oceanography, developed the autonomous PAEROS instrument package to measure aerosol particles in the surface atmosphere.

For two atmospheric scientists, however, the sea ice hasn’t been a major obstacle: Greg Roberts and Craig Corrigan, a team from the Scripps Institution of Oceanography, have been finding plenty of the small particles they came to study in the air and clouds above the station. Greg and Craig brought with them to the Antarctica an autonomous package of instruments to measure aerosols — the hundreds to tens of thousands of solid and liquid particles that are suspended in every cubic centimeter of the earth’s surface-layer air. (An aerosol technically refers to a suspension of particles in any gas; usually, and in this case, the gas is air.)

The two scientists were the inaugural speakers Oct. 31 in the 2013-2014 field season’s series of weekly “science talks.” (At Palmer, a member of the science party traditionally gives a presentation on Thursday nights to the other scientists and station crewmembers about his or her research, or on some other scientific topic.) As those assembled for the presentation on Thursday learned, aerosol particles play an incredibly important role in regulating our weather and our climate, even at very low concentrations: Without aerosol particles, for example, there would be no rain anywhere on earth.

As part of their Thursday-night lecture on aerosols, Greg and Craig demonstrate cloud formation using pressurized isopropanol in a soda bottle.

As part of their Thursday-night lecture on aerosols, Greg and Craig demonstrate cloud formation using a pressurized soda bottle containing isopropanol.

Aerosols can be natural or anthropogenic: Clouds are aerosols in which billions of tiny water droplets have condensed around dust or other “seed” particles suspended in the air. (These particular aerosol particles are called cloud condensation nuclei, or CCN — one of the many parameters Greg and Craig are measuring here with their instrument.) Volcanic eruptions, anthropogenic exhaust emissions (from factories, power plants, ships, and cars, for example), and smoke from burning of biomass in forests also add to the number of particles in our air.

The ocean, it turns out, is also an important natural source of aerosol particles: When the wind drives the ocean’s waves to crest and break, sea spray (or spindrift)  breaks into tiny droplets, sending particles of sea salt into the air. In addition, certain chemical compounds produced by phytoplankton — chief among them dimethylsulfide, or DMS — are emitted from the ocean into the surrounding air. DMS can then be oxidized to a number of other sulfur-containing compounds that serve as highly effective cloud condensation nuclei.

PAEROS weathers a coastal storm that brought sustained winds of 50 knots. Photo courtesy Greg Roberts.

PAEROS weathers a coastal storm that brought sustained winds of 50 knots. Photo courtesy Greg Roberts.

To identify the various sources of aerosols and obtain information about the particles’ physical properties, Greg and Craig have incorporated several different instruments into their Portable Aerosol Observing System, or PAEROS. The instruments within the package measure everything from the total number of particles in each volume of air to the size distribution of the particles (how many particles of what size are present) and whether those particles serve as cloud condensation nuclei, or CCN. The instrument also records several meteorological parameters, including rainfall and wind velocity and direction.

While PAEROS is autonomously measuring and recording data on the many terrestrial sources of aerosols in the air here — including those both natural and anthropogenic — Greg and Craig are equally as interested in capturing data on the various sea salt, sulfur, and organic compounds that come from the sea and are transformed into cloud condensation nuclei above the ocean. DMS, for example, is produced in the surface layer of the ocean through a complex series of metabolic processes in phytoplankton. Sea salt comes from breaking waves, and organic aerosol particles are thought to be generated by the bursting of bubbles at the ocean’s surface.

In a 1987 paper in the journal Nature, Charlton et al. described a complex feedback loop involving phytoplankton DMS production and cloud formation over the oceans.

The original “CLAW hypothesis” paper. In a 1987 article in the journal Nature, Charlton et al. described a complex feedback loop involving phytoplankton DMS production and cloud formation over the oceans.

The relationship between DMS production and cloud formation was the basis for the “CLAW hypothesis,” a complex feedback loop described in 1987 through which phytoplankton could regulate their environment through increased DMS-based cloud formation. (The concept was formally described by Charlson et al. in a 1987 paper in the journal Nature; it takes its name from the first letters of each of the paper’s authors’ last names.)

Given their many sources, aerosol particles are ubiquitous: Air in a polluted city might contain concentrations as high as 50,000 particles per cm3, Greg and Craig’s data show that even the air in a place as devoid of human activity as Antarctica can contain concentrations of 100 to several thousand particles per cm3.

Because the “signal background” here in Antarctica is so low — i.e., there are normally very few natural or anthropogenic aerosols in the “clean” air above the Peninsula here — the PAEROS instruments can detect very subtle changes in the types and distribution of particles that might be missed if the instrument were deployed almost anywhere else in the world.

But even here in Antarctica, PAEROS can find evidence of anthropogenic material in the air: One of the instruments can discern particles containing “black carbon” — complex, dark-colored graphitic compounds that are produced through the incomplete combustion of fossil fuels and biomass — from other types of particles. Against the very low aerosol background here at Palmer, even the soot from a single passing ship’s smokestacks was enough to register a signal on the instrument. (Greg and Craig have seen almost no black carbon when winds are blowing clean air off the Antarctic continent to the south; when winds blow from the north, however, they can detect small anthropogenic signals in the air coming off South America.)

A brief shift in the weather brought northeast winds — and, very briefly, open water — to Arthur Harbor. In the absence of much biological activity, the water remains extraordinarily clear.

A brief shift in the weather brought northeast winds — and, very briefly, open water — to Arthur Harbor. In the absence of much biological activity, the water remains extraordinarily clear.

Greg and Craig will both depart Palmer in the next few weeks, but PAEROS will continue to record data on black carbon and other aerosol sources here until the field season ends in March. It looks increasingly likely that one of those other sources — phytoplankton DMS production — will elude the two scientists, at least personally. Both had hoped to be present to see what PAEROS was measuring when the first bloom of phytoplankton occurred this spring. With the sea ice still firmly in place, however, the season’s first bloom is still a few weeks or months away. Once the phytoplankton starting doing their thing, Greg and Craig will have to check in remotely from California to see exactly what PAEROS is saying.

Much more science to come from down here at Palmer.

Stay tuned,

Jamie

A few images below from the past two weeks on station:

Spring days bring a twilight that last for hours. Greg makes his way up the glacier toward the rising moon.

Spring days bring a twilight that lasts for hours. Greg makes his way up the glacier toward the rising moon.

Mount Agamemnon (to Palmer's east) glows in the long spring twilight.

Mount William (to Palmer’s east) glows in the long spring twilight.

Lenticular clouds hover over the Marr Ice Piedmont.

Lenticular clouds hover over the Marr Ice Piedmont.

Two hours after sunset. The lights of the Laurence M. Gould, hove to in the ice, are visible on the horizon.

Two hours after sunset. The lights of the Laurence M. Gould, hove to in the ice, are visible on the horizon.

Greg Roberts and Oliver Ho preparing to put in a few turns on their snowboards.

Greg Roberts and Oliver Ho preparing to put in a few turns on their snowboards.

Fallout, continued

A quick update on public research funding. Dust of the post-government shutdown variety — not the aeolian sort about which chemical oceanographers get excited — continues to settle on science in Antarctica. In a statement released this week by the National Science Foundation, the agency identifies several planned (and already funded) Antarctic research projects which were cancelled altogether as a result of the lapse in funding. The good news for those few of us on this side of the continent: Because Palmer Station is served by a unique logistical operation in Chile, research planned here for later in the season will be largely spared. Several investigators who had planned to conduct field campaigns via the McMurdo logistics hub weren’t so lucky. The USAP had to cancel or defer a number of logistical commitments, including:

  • most of the support for NASA’s Long-Duration Balloon facility
  • a camp on Mt. Erebus, atop the world’s southernmost active volcano
  • a field camp for the West Antarctic Ice Sheet (WAIS) Divide project
  • and an over-ice traverse to support portions of the Whillians Ice Stream Subglacial Access Research Drilling (WISSARD) project

I can only imagine how the hard-working scientists who won grants to conduct these research efforts felt when they got the news. Let us all hope this doesn’t happen again anytime soon.

More from Palmer Station tomorrow.

Hunkered down, awaiting science

Sunset over the waters of the Bismarck Strait on Oct. 27. While each spring day brings more daylight to the Peninsula, the sea around the station remains icebound.

The sun sets on Oct. 27 over Palmer Station and the waters of the Bismarck Strait. While each spring day brings more daylight to the Peninsula, the sea around the station remains icebound.

By the hard numbers, it’s springtime in Antarctica. Each passing day brings more sun to the sky: Sunrise this morning was at 4:56 a.m. and sunset at 9:03 p.m., giving Peninsula residents over 16 official hours of daylight. Daily high temperatures have been rising slowly over the past month. And, despite almost nightly snowfall accumulations, several bird species — creatures both flightless and flying — are returning to take up residence for the breeding season.

The first penguins have returned to their spring rookeries Torgersen Island, one of the many rocky islets offshore of Palmer Station.

The first penguins have returned to their spring rookeries on Torgersen Island, one of the many rocky islets offshore of Palmer Station.

For scientists of the Palmer LTER study, however, spring has yet to arrive. After a brief clearing of sea ice that coincided almost cruelly with the now-infamous government shutdown, the ocean adjacent to the station has been solidly icebound for nearly two weeks. The sea ice — not particularly thick, but stretching in every direction, as far as the eye can see — has prevented us from launching any sort of boat to make measurements at our study sites in the waters off the Peninsula.

To be clear: The absence of new posts these past few days doesn’t mean there isn’t anything notable happening here at Palmer Station. Two groups of scientists — a pair of microbiologists from Brown University and a team of atmospheric scientists from the Scripps Institution of Oceanography — have been working busily on their respective research projects. (In my next post this week, I’ll introduce you to Greg and Craig, the two scientists from Scripps.)

After a brief clearing, a solid layer of sea ice has blanketed the waters off Palmer Station for more than two weeks.

After a brief clearing, a solid layer of sea ice has blanketed the waters off Palmer Station for more than two weeks.

Palmer’s support crew continues to keep station operations running smoothly. And a few special construction projects are underway. (Chief among these is the relocation of several storage vans — shipping containers used to house supplies and equipment — to a new home behind the station.)

But for the two LTER science teams present, the sight of a still-frozen sea over breakfast largely portends another day hunkered down in the station’s cozy yet very well-appointed laboratories. Thankfully, there is much to do: Equipment and sampling materials must be readied for the day the ice finally flees for good ahead of the coming summer. The precise date on which this great ice-out event will occur is a frequent subject of intense, half-informed lunch-table debate among the project’s biologists, chemists, and biogeochemists — none of whom, it’s worth noting, are meteorologists.

Unlike other regions of Antarctica, the West Antarctic Peninsula has seen a dramatic decrease since 1970 in the number of annual days with sea ice cover. Scientists are just beginning to understand the specific mechanisms through which anthropogenic activities have influenced this change. Data: Hugh Ducklow, LDEO.

Unlike other regions of Antarctica, the West Antarctic Peninsula has seen a dramatic decrease since 1970 in the number of annual days with sea ice cover. Scientists are just beginning to understand the specific mechanisms through which anthropogenic activities have influenced this change. Data: Hugh Ducklow, LDEO.

Vexing though it is, our icebound state is not unusual for this time of year: For the past decade or so, the sea ice hasn’t typically retreated off Anvers Island until late October or early November. And where the rapidly-changing ecosystem of the West Antarctic Peninsula is concerned, I feel in some strange way I should be thankful the ice hasn’t yet retreated: The average number of annual days with sea ice cover has been plummeting dramatically here as the region warms at a geologically alarming rate.

As human beings, we are creatures of the moment, geologically speaking. And so this alarming long-term trend isn’t a daily subject of conversation at the lunch table here, even among the many assembled human beings who are scientists. Instead, anxious to conduct the research for which we’ve traveled thousands of miles, we discuss what must happen in just the next few days — a geological blink of an eye — to break up this year’s ice cover.

Detail of NGA chart 29123, showing the orientation of Arthur Harbor, which surrounds Palmer Station. A full PDF version of the chart, which covers Anvers Island and part of the Bismarck Strait, is available for download here.

Detail of NGA chart 29123, showing the northeast-southwest orientation of Arthur Harbor, which surrounds Palmer Station. For nautically inclined readers, I’ve also uploaded a full PDF version of the chart, which covers Anvers Island and part of the Bismarck Strait.

The general consensus, among those who are return visitors to Palmer: It is not simply enough that temperatures warm. Any warming must be accompanied by a northeast wind that blows steadily for several days to push the frozen stuff out of Arthur Harbor, which faces to the southwest. (Anyone who has sailed aboard an icebreaker — this one, for example — will tell you that wind can be as much a factor in the movement and rafting of sea ice as the temperature.)

Unfortunately, northeast winds haven’t been the trend of late: After a flirtation last week with relative warmth and some brisk northerlies, we’ve had winds these past few days out of the west and southwest. The weather brought clearing on the horizon and an incredible sunset yesterday evening — but no hope of a sampling day today.

There is some hope in the latest weather outlook, however: Winds tonight are predicted to veer to the north and pick up to nearly 50 knots. (Meteorologists at the Navy’s Space and Naval Warfare Systems Center (SPAWARSYSCEN) in Charleston, S.C., provide daily weather forecasts for Palmer Station and other units of the USAP.)

We’ll be battening down the hatches this afternoon and crossing our fingers for some open water tomorrow morning. Time well-spent in the lab these past weeks will ensure we’ll be ready to sample when the sea clears.

In my next post this week, I’ll introduce Greg Roberts and Craig Corrigan, two atmospheric scientists from the Scripps Institution of Oceanography who study aerosols, the very small particles and droplets of liquid that are present in our atmosphere. Greg and Craig have deployed some very sensitive instruments to measure concentrations of cloud condensation nuclei in the air above Palmer Station.

In the meantime, some photographic proof that ice on the surface of the sea doesn’t prevent scientists from enjoying time on land:

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The sun hangs low on the western horizon on Oct. 27. Sunset over the Bismarck Strait occurred at 9:03 p.m. local time.

A few minutes later...

A few minutes later. Palmer’s BIO building is in the foreground; Torgersen Island is visible across Arthur Harbor.

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Fresh tracks on a tongue of the Marr Ice Piedmont, the ice cap on Anvers Island that surrounds Palmer Station to the east and north. Station residents just call it “The Glacier.”

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Matty Hoye, a support staff member from Colorado, scouts out the notorious Anvers Island lift lines after a good run down the glacier. Meanwhile, Greg Roberts gets in some good turns.