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A one-meter section of ice core that contains ash from a volcano Basuka and others guess erupted 8,000 years ago
Here are some more of Thomas’ answers, this time from the Hood River class. Enjoy, and don’t forget to follow up with him on experiments!
Which direction does a compass point to when you are at the South Pole? North, right? But is north “down”? We weren’t sure exactly where the magnetic South Pole is either. Can you video tape this if it’s notable?
This is a very interesting question. One I would like to follow up with an experiment. Maybe your class could help me out? Here’s what I know. The magnetic South Pole is not near the geographic South Pole, in fact it has been moving rapidly away from the pole for sometime. If you look at a map of Antarctica you might be able to find the Russian research station called Vostok in East Antarctica. The station was originally placed over the magnetic pole. The magnetic pole now sits somewhere off the coast of eastern Antarctica. While the pole may have moved, scientist later discovered a huge lake under about 2 miles of ice at Vostok. There are plans now to send a probe down to the lake to look for life. It may be possible that highly specialized microbes evolved to survive in the cold, dark waters of the lake.
Back to the magnetic pole. A compass should orientate itself along the magnetic field like it does at most other locations, so it will point towards the magnetic pole. I believe the declination at the WAIS Divide is very large, around 50°, because the magnetic pole is so far away from the geographic pole. More interestingly, the compass also needs to be corrected for inclination. The magnetic fields are very steep near the poles, so steep that to get a good reading from your compass you might need to point it towards the ground. If anyone can think of an experiment with a compass I would be happy to video tape it.
On more note on the magnetic field. Before drilling commenced I helped dig out a magnetometer. This device was being used to measure fluctuations in the earth’s magnetic field on the order of hours to days. Solar storms can cause the earth’s magnetic field to change, which can in turn affect things like radio transmissions and power grids.
We read that you saw a seal when you were over at McMurdo. Have you seen any wildlife near WAIS? What species?
Almost all the wildlife in Antarctica lives on the along the coast. The waters around in Antarctica are rich in nutrients and are able to support lots of marine life. On the continent itself, seals, seabirds and penguins are basically the extent of the fauna. No animals call the interior of the continent home. Occasionally, though birds will fly over WAIS Divide. I saw a group of 5 petrels fly over camp and a lone skua was spotted outside camp. Both sightings occurred after fairly large storms, so the birds may have been blown in by the wind.
How did you feel about the civil war game? We are all Beavers here, so don’t worry. Except Courtney and Pierce who are Ducks fans. Uh oh, I’ve started an argument…
I proudly flew my State of Oregon and Oregon State University flags during the Civil War.
Update:
We’ve just started drilling and already we’ve had some exciting cores. One in particular contained a layer of ash from a volcano. These ash layers are very important to note because they help us figure out the age of the ice. For instance, we can measure the chemistry of the ash and see if it matches up with any known eruptions. Additionally, if we can find the same eruption in another ice core we can compare the records. Though we are only speculating at this point, it is believed that this ash was from an eruption of Mount Takahe about 8000 years ago. Mount Takahe is just north of WAIS Divide towards the Amundsen Sea. If this is the case, the same eruption was also noted in the Byrd Ice Core.