I've posted before about the advantages of wintering here-- less people, more privacy, slower pace. One of the disadvantages of wintertime is the lack of science going on. In the summer there are "beakers" (scientists) everywhere, and contract workers like myself get the opportunity to soak up a lot of cool science.
There are volcanologists from New Mexico up on Mount Erebus, studying its eruptions. There are seal people in their huts out on the sea ice, glueing video cameras to seals so they can watch 'em eat. Microbiologists counting germs, physicists counting neutrinos-- a lot of cool stuff.
The beakers like to give presentations, where they explain their work to us in layman's terms. There is usually a presentation every Sunday.
Some of the research being done on the ozone layer doesn't lend itself to summer conditions, though. A team of atmospheric scientists from the University of Wyoming comes down every year to do some experiments on the ozone hole. Jen Mercer of UW gave a science lecture a couple of Sundays ago that was very informative. (http://antarcticsun.usap.gov/printArticle.cfm?id=1532).
Turns out that ozone-depleting chemicals build up in the stratosphere in the dark polar winter, and are activated when the sun comes up. That's why the UW crew likes to get here when it's still dark. They can launch a balloon in the evening, and correlate the data they get with information gleaned from the LIDAR (which I mentioned in an old post). The LIDAR is a powerful laser, aimed straight up from the Crary Lab here at Mac Town. It bounces off particles of ice in the Polar Stratospheric Clouds; reflected light tells about particle size, temperature, and altitude. PSCs, or nacreous clouds are where the chemical reaction takes place that destroys the ozone. The reason it makes a hole over the pole is that the stratospheric wind is in the form of a vortex, centered on the pole. Wind circles the pole, and extremely cold winter temperatures make a kind of atmospheric cauldron where chlorine and bromine accumulate. Add sunlight, and a catalytic reaction occurs that turns ozone into oxygen.
I've worked a little bit with the balloonatics, getting their radios and gear set up for them. A month or so ago I had to climb a tower to install a small antenna for them. It receives telemetry data from the balloon as it travels through the stratosphere. When they've made their pass, they trigger an explosive charge that separates the payload from the balloon. A parachute opens, and the device falls to the ice. Another explosive charge cuts away the parachute, so it doesn't drag it off to infinity. The balloonatics will ride out in helicopters in a few weeks to try to find the balloon payloads and bring them back in. Interesting stuff.
Learn more: http://en.wikipedia.org/wiki/Ozone_hole http://www.antarcticconnection.com/antarctic/news/2006/103106ozrecord.shtml
(Picture from the UW website http://www.uwyo.edu/ess/)
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