- Published on May 05, 2007
As I contemplated what to write on this week, I was informed of an open house at the Terra Lab on top of the hill behind Palmer Station and figured it to be a perfect opportunity for my next entry. I had never been in the building, which is located a bit further away from buildings I frequent in my everyday routine of diving and laboratory research. Upon entry, I realized I had been missing out on some exciting research occurring at Palmer Station.
Research associate Lana Cohen, Terra Lab technician extraordinaire, began the open house by explaining to the group what actually goes on in the distant building. There are a number of monitoring projects that are currently in progress in Terra Lab at Palmer Station, and all of them require very advanced equipment.
The first project introduced by Lana focuses on effects of lightning and thunderstorm activity on the ionosphere and magnetosphere. Lightning strikes produce radio waves covering a broad range of frequencies. These waves can travel in the space between the ionosphere and the earth's surface and can be easily detected on the other side of the globe. Inside the Terra Lab, lightning striking in the ionosphere from all over the globe is recorded in Very Low Frequency (VLF) in hopes that these data will aid in future advances in global radio communications.
Next Lana introduced the seismic monitoring of the continental shelf where Palmer Station resides. Here at Palmer there is a seismic sensor mounted to an old antenna foundation that is constantly recording seismic vibrations. Long-term seismic recordings indicate that Palmer Station experiences frequent earthquakes. However, these earthquakes are nothing but small shakes that would hardly register on the Richter scale. Lana refers to these small shakes as "burps." It was nonetheless surprising to learn that this place is shaking right under my feet. This seismic monitoring is part of Incorporated Research Institutions for Seismology (IRIS) and Global Seismographic Network's (GSN) long-term global seismic survey.
The two projects I found most interesting were the IMS Radionucleotide Monitoring and the UV Spectral Irradiance Monitoring. The IMS Radionucleotide Monitoring is part of the Comprehensive Test Ban Treaty verification regime on nuclear arms. An automated aerosol sampler sucks surrounding air, which runs continuously through a filter that is tested for radioisotope signatures indicative of recent nuclear arms testing. Recently North Korea tested a nuclear weapon. The signatures in the air around Palmer Station showed significant traces of radioisotopes soon after the testing.
Global warming will be a hot topic for years to come (no pun intended). The polar regions are especially susceptible to increases in greenhouses gasses and ozone depletion leading to climatological warming and glacial retreat. There are aerial photographs available through the Terra Lab that document the glacial retreat near Palmer Station since 1978.
Using UV penetration measurements the Terra Lab can estimate the rate and size of the depleting ozone layer in the atmosphere. The spectroradiometer attached to a flat area on the roof of the Terra Lab produces full sky irradiance spectra ranging from the atmospheric UV cutoff near 290 nm up to 605 nm. Long term monitoring of climate and UV penetration to the Antarctic region could aid in shining some light on a subject (no pun again) that many folks are still in the dark over.