I'm too far down valley and that snow is closing in fast. At my feet are rocks, boulders, and sand--shattered bowling balls and ball-bearings of brown and red dolerite. I'm digging a soil pit, and when the hole is knee-deep, I hit pay-dirt. Ice, actually. Three million year old glacier ice, some of the oldest ice on Earth, that's been moving as a debris-covered glacier, inching its way down valley (the absolute oldest ice is even further down the valley). I've had my eyes on the ground all afternoon, and now the clouds that were skirting the mouth Beacon Valley have marched their way up towards me. The air is filled with with swirling snow, glinting in the failing sun like harsh confetti. The temperature is dropping fast as the warm rays of the sun are swallowed up by the growing storm. I've got thirty pounds of sand and ice in my pack, and three kilometers to make it back to camp before the weather turns to whiteout. It's going to be an interesting hike... That was December of 2004. It was my first season in the Antarctic as a scientist studying permafrost (frozen ground) as part of a project to understand frozen landscapes on Mars (the "season" is summer in the Antarctic--winter back home in the US--when field work mostly occurs in Antarctica). Now it's 2010 and I'm about to embark on my fifth field season as a permafrost geologist working with the McMurdo Dry Valleys Long Term Ecological Research Project. As part of the National Science Foundation's Antarctic Organisms and Ecosystems program, I'm trying to figure out how the frozen ground in Taylor Valley feeds water and nutrients to the southernmost functioning ecosystem on Earth, and how this microbial and invertebrate "canary in the coal mine" is going to respond to changing climate conditions. Keep with this blog to find out more about the science going on in this cold, dry place. I'll be updating from a field camp with limited web access, so feel free to ask questions, think critically, and share in the adventure of polar exploration!