The Bowman Lab

A number of you have been asking great questions on the blog, unfortunately the comment format keeps these questions and answers out of view unless you go looking for them. I’ve created a new page for questions, comments, and discussion titled “Antarctic Q&A”. I hope this will serve as a more visible and user friendly forum. Keep the questions and comments coming! Of course we will still answer any questions that come through via the old blog comment threads.

Flat Stanley helps pilot the C17 to McMurdo.

We arrived safely in McMurdo last night after a five hour flight from Christchurch, avoiding the dreaded and common ”boomerang” scenario where the plane is forced to turn around close to McMurdo on account of rapidly changing weather.  The final “winfly” (winter fly-in) flight was supposed to occur today but was canceled due to an approaching storm.  The storm never materialized however, and our first day in Antarctica was calm and warm (-15 C).

Our arrival was somewhat chaotic.  The plane landed on an ice runway around 10 miles from McMurdo (there is an ice runway closer to the station, but it has developed a crack) and we spent some time taking in the change in scenery before climbing into “Deltas”, tractor/bus hybrids with extra-wide tires for the hour long crawl to the station.  We arrived in time for dinner and a series of briefs by the station manager, station doctor, and others.

Loading the Deltas. Photo: Shelly.

With the last of our energy we took a tour of the Crary Lab building (named after the pioneering Antarctic researcher Albert Crary), where our laboratory and other works spaces are located.  It’s exciting to be at McMurdo and to see the tools and space we need to do our work, but daunting to think about the challenges we will need to overcome in the coming weeks!  Foremost among those challenges will be lobbying the science supervisors for access to open water.  But before we can do that we need to complete a long list of trainings (on vehicles, vehicle maintenance, radios, survival, etc, etc…), find our equipment (most of which hasn’t arrived yet), and get our lab spaces organized and operational.  We will hit the ground running on Monday morning!

McMurdo Station. The large blue building center right is the dining facility and station store. The Crary Lab building is almost out of site behind the large tan building in the left foreground. The Dellbridge Islands can be seen on the horizon to the right. Photo: Shelly.

Much of downtown Christchurch remains closed off 6 months after a devastating earthquake.

We arrived in Christchurch, NZ last night via Los Angeles and Auckland.  We weren’t the only ones, almost everyone on our flight from Auckland to Christchurch were staff heading to McMurdo to take the place of the winter personnel.  After a much needed night of sleep Shelly and I set out to explore Christchurch.  Christchurch was hit with a major earthquake on February 22 and we were keen to view the reconstruction.  Much of downtown Christchurch is still off-limits to everyone except for demolition crews, but we were able to walk around much of the perimeter.  The reconstruction has been going slowly in part due to continued aftershocks.  A total of 4305 (and counting) tremors have been reported in the Christchurch area since February 22^nd.  Click this link to view a very informative time lapse of earthquake location, magnitude, and depth (and important factor in how damaging an earthquake is) for all of these tremors.  This time lapse works well as an illustration of how energy contained in a fault slip is dissipated over time.

After touring Christchurch we visited the USAP clothing distribution center to get our issue of cold weather gear.  Two duffel bags later we stashed our issue for tomorrow morning’s departure and headed back into town.  If (and it’s a big if) all goes according to plan we will get up at 3 am tomorrow morning to rendezvous with our flight at 4.  Departure is scheduled for 7.  HOWEVER, weather has grounded flights on the 24^th and 25^th.  We were fortunate to get bumped to that flight’s third attempt, the rest of our original flight will sleep in tomorrow and hope for good weather on the 28^th!  As of right now the forecast isn’t promising for either flight, so we shall have to see what tomorrow brings…

We also received word today that the National Science Foundation (which funds and oversees the USAP) has contracted with a Russian icebreaker Vladimir Ignatyukto break out McMurdo Station this year.  Sighs of relief all around the Antarctic scientific community!

Which way will we be doing things?  I’ll give some details on that in a moment.  First, with less than 72 hours until we depart for Christchurch, NZ, we’ve gained a new member of our expedition; Flat Stanley.  Flat Stanley joins us from Mrs. Garrigues 2nd grade class at Methow Valley Elementary.  He is, reportedly, a bit of a show off and will probably manage to work his way into a number of photos.  However with the amount of work we have planned we are happy for the extra help!

On the surface our project seems pretty straightforward, and it is.  Collect samples of marine water, young sea ice, frost flowers, mature sea ice, and similar environments and analyze what DNA, RNA, and proteins are contained within the microbial community.  The DNA sequences tell us which bacteria are present and what metabolic processes they are capable of.  The RNA sequences tell us which metabolic processes they are currently using (genes are transcribed into messenger RNA which is translated into proteins and then quickly destroyed by special enzymes called ribonucleases).  The protein sequences extend this concept further, telling us exactly which enzymes are present and active within the environment.  In this study we are focusing on extracellular enzymes which play a crucial role in polar carbon cycling and other processes.

The challenging part is that each of these analyses requires a substantial number of microbial cells and therefor a substantial amount of sea ice.  We anticipate needing to sample up to 800 kg (~1700 lbs) of ice from some of our sites.  To prevent changes to the microbial community before analysis all of this ice has to be carefully melted into a high salinity brine near the freezing point, a very time consuming process.  Once melted each samples must be filtered to concentrate the cells from the liquid, a process which takes many hours.  I’ll be talking more about exactly why and how we do this once we get some samples to melt!  It’s time to start packing and making the final preparations to head south…

One more items of interest, the journal Science ran an article on the icebreaker situation in Antarctica that can be found here (any educators that do not have access to this journal but would like a copy of this or any other publication cited on this blog can email me).

 On Friday I had the opportunity to speak with Karen, the McMurdo Station staffer in charge of field safety.  Karen has a difficult task, coordinating the safe operations for a diverse array of field projects throughout the season.  Aiding her in this is a staff of experienced guides.  These individuals are responsible for training the science teams for safe travel over sea ice and glacial terrain, scouting hazardous terrain, and accompanying the science teams on their initial forays into these areas.  By November, when most scientists begin to arrive at McMurdo, the staff will have thoroughly scouted the surrounding area and established safe zones of transit over the sea ice and glaciers.  When we arrive in late August we will have the privilege of being the first to venture out onto the sea ice of McMurdo Sound this year.  We hope to travel all the way to the sea ice edge near Cape Evans (see map below), which according to Karen is unprecedented for the USAP this early in the season. 

 With the privilege of being first out comes several challenges and some responsibility.  Only two guides are presents at McMurdo until mid-October, so our team must be reasonably self-sufficient.  The weather will be unpredictable and temperatures pretty low.  Added to this is the need to travel over very thin, young sea ice to collect frost flowers (see previous post).  Falling through this thin ice, hours from McMurdo, in very low temperatures is an unpleasant thought.  To guard against this we will employ safety tethers, life jackets, and drysuits while sampling.  One team member will stand on thick ice, managing the safety tether for the team member actively sampling.  This system has worked well for us on sea ice near Barrow, Alaska.  Hopefully it works equally well in Antarctica!

The map below shows Ross Island, home to McMurdo Station.  The station is located on the strip of land projecting from the lower left of Ross Island.  North from the station, past the tongue of Erebus Glacier, are the Dellbridge Islands.  This island group is our first target, as open leads can be found here throughout the winter.  After exploring the Dellbridge Islands we will start traveling further north from McMurdo, toward Cape Evans.  We expect to encounter the ice edge near here, and this is where we will spend most of our time.  Unfortunately this is several hours from McMurdo, and we have to return to the station each night!

 If we can’t find the right ice conditions here we will need to wait until the station’s helicopters are operational to travel further out.  This won’t happen until mid-October, but with the helicopters we can reach almost anyplace around Ross Island.  Highly variable ice conditions west of Cape Crozier, toward Cape Tennyson and into Lewis Bay, will provide lots of opportunities…

Laboratory grown frost flower.

When sea ice forms during the polar winter it is often possible to observe the growth of frost flowers, intricate structures that are composed from frozen atmospheric moisture and from brine wicked from the sea ice surface.  The transport of brine into these structures means that they are unusually salty, up to 5 times the salinity of the ocean.  By this same mechanism other things in seawater concentrate in frost flowers, including bacteria.  For the last two years we’ve been traveling to Barrow, Alaska to collect frost flowers in an effort to understand which bacteria are concentrated at the sea ice surface.  Several important processes at the ice surface, including the production of aerosols and reactive organohalogens, are likely to be influenced by these bacterial.  In addition since the surface of sea ice is very cold this is a great place to study how bacteria adapt to extreme conditions.

Frost flowers over young sea ice in the central Arctic Ocean. Photo Matthias Wietz.

Although frost flowers are very abundant in the Arctic and Antarctic getting to them isn’t easy.  The ice underneath them is often too thin to walk across and prone to drifting with the wind.  The basic sampling strategy is to find a place where the water is kept open by winds or currents (called a lead if smaller and short lived, polynya if larger and more permanent), stand on the thick ice at the edge, and hope the wind drifts the newly forming ice and frost flowers within reach.  This is not ideal!  Our new project in Antarctica is a continuation of this effort to characterize the microbes at the sea ice surface.  With luck we will find a range of better options for accessing these regions of new sea ice growth within McMurdo Sound.

Ice algae on the underside of Arctic sea ice

The Deming research group focuses on microbial life within sea ice.  This seems like a pretty esoteric topic until you consider the extent of sea ice in both polar oceans and the subpolar seas (such as the Baltic Sea) and the abundance of photosynthetic life there.  The picture above by the Soviet researcher Ivan Melnikov is an excellent example of this.  The long dark strands growing from the bottom of the ice are chains of diatoms, single celled photosynthetic organisms.  At times the bottom of Arctic and Antarctic sea ice resembles a savannah turned upside-down, and like a savannah all of this photosynthetic biomass fuels a rich ecosystem.

Jody Deming often refers to sea ice as an “inverted benthos”, meaning that it in some ways resembles the seafloor (but upside-down).  If we combine this idea with the savannah concept we can start to see why microbes play a critical role in maintaining all this growth.  Soil, as any farmer can attest, is more than just dirt.  In addition to the little bits of rock and organic debris that provide structure it contains a very active community of bacteria and archaea (single celled organisms that resemble bacteria but are evolutionarily as distant from bacteria as we are).  These bacteria and archaea are responsible for providing many of the nutrients plants need for growth and for recycling old and dead plant material. 

Exactly the same dynamic plays out in sea ice, with bacteria specially adapted to the sea ice environment providing nutrients to and recycling nutrients from diatoms and other phytoplankton.  These diatoms in turn feed copepods, krill, and small fish, and through them larger and larger organisms.  In the next post we will start to explore how Shelly and I will use the tools of molecular biology (namely the sequence identity of RNA, DNA, and proteins) to further our understanding of the role microbes play in maintaining rich polar marine ecosystems.

There were undoubtedly some racing pulses among Antarctic researchers this weekend with the announcement that the Swedish icebreaker Oden would not be available to break a shipping channel to McMurdo Station during the Austral summer.  Without a shipping channel no resupply ship can reach the station, limiting resupply to what can be brought in by air.  If a replacement icebreaker cannot be found McMurdo and the Amundsen-Scott South Pole Station will have to reduce operations to an absolute minimum to make fuel and other supplies last for another year.

We are keeping our fingers crossed for our project.  Since we are coming in early in the season and don’t require a lot of resources we are hopeful that, even if a replacement is not found, our field season will still happen! 

So why does the US Antarctic Program use a Swedish Icebreaker?  Once upon a time the US had icebreakers capable of doing the job, but the US Coast Guard icebreaker fleet has fallen on tough times.  Icebreakers don’t come cheap, one capable of breaking the thick ice of McMurdo Sound (or the high Arctic) has a price tag nearing 1 billion USD.  The cold war fueled investment in two such vessels, the Polar Star and Polar Sea.  After years of service neither vessel is fit for polar operations.  The Polar Star is scheduled for a return to service after refit, the Polar Sea appears destined for decommission.  That leaves the US with one heavy icebreaker, the Healy.  Healy could do the job but is a dedicated research icebreaker tasked to the Arctic.  Retasking it to save Antarctic science would mean a major disruption for Arctic science. 

The United States is a major player in both polar regions.  It is by far the wealthiest of only six countries that border the Arctic Ocean.  With the privilege of an Arctic shoreline comes great responsibility.  In order to fulfill our scientific obligations, conduct search and rescue operations in the face of increased Arctic Ocean traffic, and secure new northern shipping lanes a modern icebreaker fleet is needed!

After nearly 20 years in the Arctic the Deming Ecosystem is undertaking its first Antarctic study.  Shelly and I depart from Seattle on August 23rd, keep an eye on this site for information, pictures, and updates on our activities.  Questions and comments from the public, and in particular from students, are strongly encouraged!