Satellite Remote Sensing of Extreme Snowpack Melting on Eagle Island, Antarctica

Abstract:

Snow’s albedo, or how much sunlight snow reflects back into the atmosphere, is extremely high, reflecting about 80 to 90 percent of incoming sunlight. This is important for Earth’s energy balance because it reflects solar energy back into space, which helps cool the planet. Polar regions are very sensitive to climate change and therefore it is important to monitor the variability in snow accumulation at high latitudes. Eagle Island, a small island off the northern tip of the Antarctic Peninsula, is experiencing occasional events of extreme snowpack melt, some of which have been reported in the news. By using observations from NASA’s Earth Observing System (EOS) project, particularly the TERRA satellite, we can examine these snowpack changes on Eagle Island. The sensor that provides these observations is the MODIS (Moderate Imaging Resolution Spectroradiometer), which tracks a wider array of Earth’s vital signs than any other instrument aboard TERRA. In this study, MODIS observations of snowpack on Eagle Island for the past 20 years are analyzed to find climatological means and anomalies in snowpack to characterize extreme events. Relevant atmospheric climatic indices are analyzed to see if they are related statistically to recent, extreme snowpack melts. Studying these statistical associations helps us understand how extreme snowpack events are related to climatic variability in a localized region of Antarctica, and may contribute new information to the global warming discussion.