News from the polar regions during May included an interesting safe haven for viruses, continuation of the legislation regarding polar bear protection, and new uses of technology to monitor ice sheets and glaciers. Missed these stories the first time around? Read on!

What happens to viruses in between pandemics? New research suggests that the ice of the Arctic region may be a safe haven of sorts for avian flu, smallpox, and other viruses. Scientists hypothesize that the viruses are deposited in the region by migratory birds, where they remain for hundreds and even thousands of years. When the ice melts, birds transport the viruses south where they can infect again. If enough time has passed, the current population may not have immunity to the particular strain, and an epidemic could result. More research is needed to understand how these viruses might withstand the cold temperatures that typically disrupt the viruses’ membranes.

The increased mobility and decreased strength of Arctic sea ice may contribute to its faster-than-expected decline. Scientists analyzed the paths of buoys anchored in Arctic sea ice and found that the drift rate and deformation rates of the ice have dramatically increased over the last three decades. Ice that deforms often fractures, exposing open ocean water or traveling out of the Arctic via the Atlantic Ocean. The strength and mobility of the ice thus factor into the “positive feedback loop” in which warming melts ice and exposes darker ocean water, which absorbs solar radiation and in turn causes more warming and further melting.

Many polar marine animals (such as polar bears and seals) have relatively high levels of mercury from airborne particles released by industrial activities. A new study of ringed seals provides evidence to suggest that high mercury levels may be linked to declining sea ice. In the study, both short and long “summer ice-free seasons” where linked to higher mercury levels, possibly as a result of seals’ food supplies. This suggests that as sea ice declines, polar marine mammals may be more susceptible to ingesting high levels of mercury.

The Obama administration, for now, has decided to maintain the conservation rule for polar bears set forth by the Bush administration in May 2008. While the polar bear was ruled a “threatened species” under the Endangered Species Act, the administration also stated that the ESA was not the proper mechanism for curbing greenhouse gas emissions that are responsible for sea ice decline.

A research project called CAVIAR (Community Adaptation and Vulnerability in the Arctic Regions) is collecting data about challenges facing Arctic communities in light of climate change. The project is a dialogue between researchers and local residents and will present case studies across all eight Arctic nations.

Drilling projects are helping researchers reconstruct climate history in a number of ways. In the Siberian Arctic, cores from the El’gygytgyn meteorite impact crater will provide a unique archive of the region’s largely unknown climate history. A scientific research cruise has recovered nearly 53 million years of climate history from the seafloor. While such projects are expensive and logistically challenging, their data is extremely valuable in reconstructing past climates and predicting the effects of climate change.

NASA scientists are testing two new airborne radars on a two-month expedition to Greenland and Iceland. Both use pulses of microwave energy to produce images of Earth’s surface. One detects and measures the flow of ice sheets and glaciers as well as subtle changes caused by earthquakes, volcanoes, and landslides. The second will create high-resolution images of the topography of ice sheets. These types of instruments are important for scientists as they monitor how ice sheets and glaciers respond to the changing climate.

Sonar technology is being used to learn about the Antarctic ice sheet at the end of the last ice age (around ten thousand years ago). The continental shelves around Antarctica provide new clues about the speed and flow of the ice sheet, which may help scientists better predict Antarctica’s role in future sea-level rise.

The West Antarctic Ice Sheet (which lies below sea level and is thus less stable that the higher-lying East Antarctic Ice Sheet) is of particular interest to those studying climate change and potential sea level rise. A new study suggests that while a total or partial collapse of the WAIS would not raise sea levels as high as previously estimated, U.S. coastal cities like New York, Washington D.C., and San Francisco would still be at risk.

Know of another important news story from April that you’d like to share? Have a comment about one of the stories mentioned above? Post a comment – we’d love to hear from you!