Monday, June 11, 2007

Summit Camp, Greenland

Last night, the wind blew hard. There were periodic white out conditions. However, it was not that cold. It is strange in be in a snow and ice covered place, and have it get warmer when the wind blows. There was good news for our team. Indications of bromine and bromide showed up in the data. Both are in their scientific models. The best days to observe either is on windy days.

I went out to the ice coring camp this morning with Sara Wheeler (author; Terra Incognita, and other books). We rode out about six kilometers (four miles) on a sled attached to a snowmobile. I know we were traveling fairly slowly, but holding on to the railings of a sled traveling into a headwind made us feel like we were flying. Cover picture courtesy of

Researchers are drilling cores that will date back about five hundred years. They are trying to identify evidence of volcanic eruptions. In addition to rock (lava, pumice), water, and carbon dioxide, other materials are given off when a volcano erupts. One of these substances is sulfur in the form of sulfur dioxide. Eventually, in the atmosphere, sulfur dioxide is converted into sulfate. There, sulfate combines with other chemicals, and precipitates in rain or snow. On Greenland, snow never melts, and a datable, historical record of climatic events is formed. The top layers contain the most recent records, and deeper levels contain older information.. Ice coring mines this information... This group of scientists is examining sulfate.

Sulfur has different isotopes. An element's atoms all have the same number of protons. For example, all atoms of sulfur have sixteen protons in their nucleus, and most of the atoms have sixteen neutrons. However, some atoms of sulfur have 17, 18, 19, or 22 neutrons in their nucleus. This group of atoms of sulfur are called isotopes, and in the case of sulfur some are radioactive. Volcanic eruptions leave a radioactive fingerprint that can be identified. The ice core scientists hope to find evidence for volcanic eruptions in the ice cores using isotope fingerprinting. To do this, they will examine the isotopes of sulfur found in the deposited sulfate. Right now, they are about seventy feet down (still in the firn layer) or about two hundred years in the past. History buffs... your assignment is to list events, and persons famous 190-210 years ago.

In addition to talking with the scientists, we completed the digging out and the sprucing up of a backlit pit in the neve (new snow) and firn (old snow). Now stairs can now take you down about four meters (a bit over twelve feet). In front of you will be a thin, untouched snow wall, and on the other side of the wall will be another pit (no stairs). When the sun shines on the wall without the stairs, individuals on the stair-side are treated to a beautiful, backlit display of snow layering. It is a beautiful blue. Quite a treat!

We walked back to Summit Camp. It was a balmy -5 degrees Celsius (23 degrees Fahrenheit). A light wind was blowing from the west, and the sun was shining brightly. I took off my parka, and walked wearing my T-shirt. I did not want to sweat. Sweating in these conditions is not a good idea. One can easily switch from overheated to cold, and slip into hypothermia. Interestingly enough, it is not frostbite that kills, rather it is hypothermia. So, the idea is to be active up to, but not including sweating. Layering is a great way to control your body temperature.

It was a fun adventure.

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