11January2010
Gas bubbles in a small section of ice core.
Thin sections of glacier ice are incredibly beautiful. I love to gaze into these clear windows filled with little bubbles; some spherical, others oblong, all holding ancient air. The ice refracts light from its crystal faces into multiple planes of shimmering color. I see them as lovely sculptures, but scientists prepare them to study the physical properties of the ice core. I spent some time in the Arch at the WAIS Camp to learn a bit about this aspect of ice research with John Fegyveresi, who works with Richard Alley of The Pennsylvania State College.
Crystal grains can just be made out in this photo
He is at the WAIS field camp to prepare thin sections from every 20 meters of the ice core. These will be sent back to the National Ice Core Lab, where they will be photographed and measured in a variety of ways. One feature to quantify is the bubble number density. There is a measurable relationship between the density of the gas bubbles and temperature. John is developing a method of counting bubbles in a section as well as describing their shape using digital imaging and software. This information goes into a model with other data to reconstruct past atmospheric temperatures and further understand glacier movement and dynamics.
A section of ice being smoothed on a microtome
Watching him prepare his slides, I couldn’t help but think of myself and other artists in our studios creating lovely objects. He begins by shaving a section of the ice core with a microtome. The first smooth side is frozen to a glass plate with water, which doesn’t take very long in the Arch (kept at -27C degrees). The other side is then smoothed and glued with a special adhesive that works in low temperatures. The goal is to have a perfectly smooth seal of the glass to the ice. The slide is then carefully packed to be shipped with the other cores to the National Ice Core Lab in Denver. There the sections will be cut like an open face sandwich. One side will be used to study the gas bubble structure; the other side will be used to study ice crystal or grain qualities.
7January2010
If you can't see the ice runway, then your plane will not come.
Many people here have stories of boomerangs, delays and canceled flights trying to get to or from Antarctica. So I must embrace my situation as a quintessential experience of visiting The Ice. I was originally scheduled to fly out of McMurdo Station for Christchurch, New Zealand on January 5th. This process began the evening before at “bagdrag”. All passengers (or PAX as we are called) literally drag their bags up the hill (or more likely get a shuttle ride) to check in. We must have our Extreme Weather Gear (ECW) in tow. Checked bags are weighed first, then me, with my ECW and carry on bag in hand. That was the last time I saw most of my clothes and equipment.
Hiking around Discovery Point at night
The next day, I awoke to learn that my flight had been canceled earlier that morning, so took a walk around town, made what I thought would be my last sketch of Mt Discovery and explored Crary Lab and other nooks and crannies. I also got a chance to see the freezers that house the ice cores from the WAIS Project. To my great reassurance I was given the third degree before the cargo folks figured out who I was, why I might want to see the containers and took me out to see them. The freezers are checked at least 6 times a day to insure their function. From the moment they come off the plane from WAIS, to the moment they are loaded onto the ship northbound, they are cared for by cargo staff. It was great to chat with the friendly guy who happily showed me around the storage area.
Freezers full of very valuable cargo, bound for the United States
The next day, though conditions hadn’t improved, we were instructed to meet for transport to the ice runway. On the way out in the fabulous Ivan the Terra Bus, wind was blowing snow around and we all knew that this was a journey in futility. But the plane had left Christchurch and was a half hour away from the station. There was a sliver of hope that the wind would die down long enough for the plane to land. Especially since among other Distinguished Visitors (DV’s), Sir David Attenborough was aboard, coming to film on the continent. But the flight was aborted or “boomeranged” and returned to Christchurch.
This morning (January 7th) I woke to heavy snow fall and winds, though the plane was initially on delay, it was soon canceled again and I set about hand washing my meager collection of undergarments and am trying to keep myself entertained – hence this story. I also sketched the view from Crary Library again – when in doubt, look at something. Hopefully the clearing weather this afternoon sticks around and the next time you hear from me I will be in New Zealand.
Sketch of the Brown Peninsula and the Pyramid in the distance
4January2010
The weather station at WAIS is monitored several times a day to determine wind speed & direction, temperature, pressure and ceiling hieght. Sometimes a weather balloon is launched to confirm the cloud ceiling for aviation.
Weather drives everything in the United States Antarctic Program; flights happen or don’t, camps get re-supplied or don’t, work progresses or doesn’t. Even moderate winds in sub-freezing temperatures can make outdoor work difficult or impossible. Of course knowing weather conditions would make planning that much easier. But predicting the weather here is more complicated, and less precise than I realized.
Most of us are used to “double doppler” radar and other advanced technology to help us plan our day. Though weather becomes difficult to predict more than several days in advance, we can usually rely on the 48 hour forecast. But there is far less satellite coverage and monitoring in Antarctia than almost anywhere else in the world. I spoke with Mike Carmody the head of meteorology for Raytheon in support of the USAP, who, lucky for me, was stationed at WAIS to learn a bit about how weather observations and forecasts are made.
There are two centers in the United States that monitor conditions here. First is the Antarctic Meteorological Research Center at the University of Wisconsin-Madison. They collect and distribute the data from approximately 140 automated weather stations installed around the continent (to compare, the US has weather monitoring every 40 miles or so) and manned stations operated by the US and other nations. The other is the Navy’s Space Warfare Center, a civilian naval facility in Charleston that takes this data, plus satellite and ground observations from several locations to forecast the weather for aviation.
Like all weather forecasting, a model is used to predict conditions in the future. But here is the thing to remember, models used to predict weather in the United States are informed by over 100 years of continous weather data. Antarctica has only been continously occupied for 50 years, and only in a few locations. So the model that is used to predict weather here is based on very scant data. Plus there is the added complication of conflicting information between satellite and ground observations. The satellite picture gives a broad sweep, but cannot see under the clouds to determine visibility, etc. The ground observer can describe current conditions accurately, but cannot see beyond that. So operations has to weigh all of this information before sending planes into the sky risking that they might not be able to land in poor visibility and flat light.
Watercolor sketch of my beloved "Big Red"
It really drove home for me another important goal of the ice core being acquired at the WAIS Divide. Data from the core will give very accurate information for annual temperatures and atmospheric conditions for the past 10,000 years. This will be added to the weather models to improve predictions. In the meantime, I don’t ever go anywhere in Antarctica without my Big Red (the high loft, very warm coat issued to all participants in the USAP)!
2January2010
On top of OB Hill, the Ross Ice Shelf and Black Island in the background. It's warmer here!
McMurdo Station – Happy New Year! I am working on a few blog posts for the new year, so stay tuned. In the meantime, check out the blog of a science graduate student Heidi Roop, who is working at WAIS. She is sponsored by the Exploratorium in San Francisco and took great video equipment into the field. These will be posted once Heidi returns to McMurdo in February. Exploratorium:Ice Stories
31December2009
December 31, 2009
WAIS Divide Camp at 79.47° S latitude, 112.06 W° longitude – high on the West
Antarctic Ice Sheet Plateau.
I am sending off 2009 with a flight out of WAIS Camp to McMurdo Station. It
will seem like the tropics to me since it is above freezing there. Though I
am sad to be leaving the WAIS community full of fabulous people, I am glad
that my flights are working out almost as scheduled.
Tomorrow there is a big music festival at McM called IceStock – too bad I
forgot my tie dye!
There are a couple of blogs in the hopper that will be posted in the next
few days AND PHOTOS!!!!!
Stay Tuned and Happy New Year!