Ice Stories: Dispatches From Polar Scientists » Seuss Glacier http://icestories.exploratorium.edu/dispatches Mon, 15 Nov 2010 20:40:36 +0000 http://wordpress.org/?v=2.9.2 en hourly 1 Dry Valleys: Looking for Life on Mars http://icestories.exploratorium.edu/dispatches/dry-valleys-looking-for-life-on-mars/ http://icestories.exploratorium.edu/dispatches/dry-valleys-looking-for-life-on-mars/#comments Fri, 02 Jan 2009 18:26:10 +0000 Mary Miller http://icestories.exploratorium.edu/dispatches/?p=1474 LAKE HOARE, DRY VALLEYS, ANTARCTICA– After spending time at the South Pole, flying to Cape Royds and Black Island, and otherwise keeping ourselves busy with webcasts and scientist interviews in McMurdo, Lisa and I hopped on a helicopter out to the Dry Valleys for a couple of days of hiking and camping in the coldest, driest desert on Earth. Our base was the Lake Hoare field camp nestled next to the Canada Glacier.


Canada Glacier with frozen Lake Hoare in the background.

Summer melting from the Canada Glacier feeds a stream that flows into Lake Hoare.

The Dry Valleys are dry because very little snow falls here, the average water content is less than a centimeter. Yet a fully functioning ecosystem exists here, in the ice-covered lakes and the soils of the valley floor. Even though the ecosystem is all but invisible to the naked eye, it still has a basic food web: primary producers (mats of moss and algae in the lakes, bacteria, yeast, fungi and other microbial life in the soils ), grazers (microscopic invertebrates called rotifers and tardigrades), with the top of the food chain consisting of tiny nematode worms. Curiously, there are no known predators in the Dry Valleys soils. These valleys constitute a Long-Range Ecological Research (LTER) study site and represent what scientists believe might be a model for life on Mars if it exists.


Lisa Strong on a hike with Canada Glacier behind her.

The origins of Seuss Glacier pouring through a mountain pass in the Dry Valleys.

Lisa and I went for a walk up the Taylor Valley to see whether we could uncover any evidence of life and saw little, except for a couple of long-dead seal mummies (why they traveled so far from the sea ice is anyone’s guess) and some algae-covered rocks and brown floating scum, looking for all the world like whipped chocolate mousse. We did see plenty of wind-scoured rocks and glaciers pouring through gaps in the surrounding mountains.


Bones and skin of a seal mummy that perished hundreds or thousands of years ago.

Biological scum on Lake Chad.

For easier walking, I tried to cross the moat between land and solid (white) lake ice. What I thought was thick ice wasn’t and I broke through up to my knees for my own version of the polar plunge. After changing into dry pants and socks, we continued on our walk but the only macroscopic life we saw was a lone skua winging up the valley.


Mary after breaking through lake ice.

I knew I needed to dig deeper, so I’ll turn to the LTER scientists studying the different parts of this ecosystem from the glaciers that feed life-giving water to the lakes and soils, to the ice-covered lake waters that support microbial life, to the soils that provide habitat to bacteria, yeast and fungi, and invertebrate creatures that make up “charasmatic megafauna” of the Dry Valleys. Look for upcoming video interviews with these LTER scientists.


Glaciologist Hassan Basagic of Portland State University explaining the dynamic of Canada Glacier to Lisa.
]]>
http://icestories.exploratorium.edu/dispatches/dry-valleys-looking-for-life-on-mars/feed/ 5