Deprivation

Life is pretty comfortable in Antarctica, especially in McMurdo. There are things we learn to live without. Fresh food of any kind is a limited commodity. I recently purchased crackers from the station store that expired in 2006, but they tasted OK. This fresh fruit showed up in the office about a week ago and whoever brought it back from the galley is out in the field for the next few weeks. There is a hoarding instinct that kicks in here. Fresh foods of any kind are limited, so there is a tendency to hoard just a little bit of it. But then, people watch it shrivel up because they couldn't bring themselves to actually eat it since it may be the last real fruit they see for a long long time. It's understandable.
When we are in Antarctica, we surround ourselves with a few comforts of home or things that remind us of home. I personally think that the barren brown and white landscape of Antarctica can be quite beautiful, but we do enjoying surrounding ourselves with pictures of warmer places, happy times away from here, photos of family and friends, fresh food and fake flowers.

Lake Brownworth

Here are a couple more pictures from the trip the the Wright Valley yesterday. We hiked to Lake Brownworth, a pro-glacial lake on the margin of the Wright Lower Glacier. Most of the lakes in the dry valleys are closed-basin lakes, meaning that water flows in, but it doesn't flow out. Lake Brownworth is different because meltwater from the glacier flows in, but the lake is drained by the Onyx River, the longest river in Antarctica. As I mentioned in my previous post, the Onyx flows away from the coast inland to Lake Vanda, which is a closed-basin lake. Lake Brownworth has a permanent ice cover like most of the lakes in the dry valleys. It also appears to have a significant amount of algal mat. You can see dark chunks of this mat material that worked its way up through the ice over many years and is still frozen to the surface. We were optimistic as we walked closer that the dark material might be wind-blown sediment, but as we got to the shore we could see that it was all algae. Because Lake Brownworth has a river draining it, the lake level must stay fairly constant. I mean, the lake level could drop, but it can't get any higher because of the river. There is a bathtub ring of algal mat marking the perimeter of the lake.

Wright Valley

I had a great day in the field with Kelly. We went to the lower Wright Valley and I was her field assistant for the day. Now that Kelly is looking for wind deposited sediments around the dry valleys, I am training my eye to look for these features. We spent a couple of hours hiking around to look for good sample locations. We saw this hillside covered with sand and hiked over to it. The grains were pretty big sand size particles, but they seemed to be rounded like little ball bearings. Kelly walked up the slope to sample and I waited at the bottom of the hill so that I would not disturb the slope any more than necessary. Kelly looks like just a speck in the picture.

Looking back down the hill, the sand looked like snakes moving across the surface. It was only blowing about 10 knots while we were there, so there was not much movement of material.

We also came across a large ventifact that had collected sand inside, so Kelly sampled the sand there too.
The dry valleys are windy and there are signs of wind everywhere. This box belongs to the LTER stream team and it houses the equipment used to measure flow at the stream gauge on the Onyx River. I noticed that all of the paint on the west side of the box had been sand-blasted away. The other sides of the box looked almost freshly painted. The biggest wind storms in the dry valleys come from the west, although most of the sand features that we found appear to be deposited from the east.

When we arrived, we landed near the Onyx River at the helicopter landing site that the stream team uses when they visit the site. So after we finished our work, we waited by the river for the helicopter to come and pick us up. The Onyx River is the longest river in Antarctica and it flows away from the coast and drains into Lake Vanda. It is not very big compared to rivers at home, but it was flowing pretty well that day. It was still a few degrees below freezing, so I'm sure the flow will pick up as the sun gets higher in the sky and it warms up over the next couple of weeks. The water looked fresh and clear, but I didn't have a chance to drink it.