News from the polar regions in November 2008 included many climate change-related reports, the fifth largest ozone hole on record, new marine discoveries, and new polar research projects. Missed these stories the first time? Read on!

Is the winter thinning of Arctic sea ice driving the summer record lows? That’s the question many scientists are asking. Last winter, the thickness of Arctic sea ice fell by nearly half a meter as compared to the average thickness of the previous five winters. In summer 2008, sea ice was at it second lowest extent ever, despite a relatively cool season. Scientists believe that the thinning ice contributes to greater summer melting, even without unusually warm weather.

Anthropogenic greenhouse gas emissions have long been implicated as a major factor in Earth’s warming climate and Arctic sea ice decline. Now, researchers from the University of East Anglia state that their new work demonstrates that human activity is responsible for significant warming in both the Arctic and Antarctica. Updated data and simulations from new climate models show that the temperature increases in the polar regions are not consistent with natural climate variability alone. Warming from human activity has already impacted polar biology, ice sheets, indigenous communities, and global sea level.

Changes in ice sheets and sea level are two widely publicized effects of climate change, but both are difficult to predict and model. Scientists use satellites to monitor changes in water levels in the sea, rivers and lakes, ice sheets, and even under the ground. One new satellite technique shows that about 80% of the annual sea rise (about 3.3 millimeters a year) can be attributed to the loss of land-based ice in places like Greenland and Antarctica. This is a change from the 1993-2003 decade, in which scientists calculate that sea level rise was equally the result of shrinking land ice and ocean expansion. Other satellite data has helped scientists determine that the filling and draining of subglacial lakes in East Antarctica caused a rapid, temporary acceleration of Byrd Glacier. The work shows that these lakes are not stable and inactive as previously thought, and that glaciers are quite sensitive to change.

An international team of researchers are set to explore two immense ice-covered basins in the East Antarctic ice sheet. The researchers will measure the thickness of the ice sheet and characteristics of the rocks below the ice in an effort to model East Antarctic ice stability, predict the ice’s reaction to climate change, and show its potential impact on sea level.

Melting Arctic ice sheets and glaciers release cold, low-salinity water into the North Atlantic Ocean, resulting in shifts in the geographic range of many plants, and animals. The influx of polar water can also extend the growing season of phytoplankton and zooplankton and alter ecosystems from the bottom of the food chain upwards. Researchers studying these changes note that there will be both “winners and losers” in terms of marine species and the people who depend on the ocean for a livelihood.

If more severe consequences of climate change are to be avoided, atmospheric carbon dioxide levels must be reduced below the levels that already exist today, according to a new international study. The authors of the study state that carbon dioxide levels are already in a “danger zone” and call for the phasing out coal use except where the carbon dioxide can be captured or sequestered.

The ozone hole over Antarctica grew to the size of North America in its fifth largest maximum ever. The hole fluctuates in size in response to sunlight and temperature, reaching its annual maximum extent in September.

New discoveries in Antarctica are exciting polar biologists. Recent discoveries include microbial life in lakes of liquid water underneath the Antarctic ice sheet and many new marine findings. Molecular evidence shows that a large proportion of deep sea octopus species evolved from common ancestors that still exist in the Southern Ocean, and many new species of sponges, amphipods, sea cucumbers, and cnidarians have been discovered there as well. In the Arctic Ocean, marine biologists have discovered a rare site with a rocky seafloor, home to a diverse community in comparison to the soft and silty coastline that is common in the region. New species of Arctic jellies and zooplankton were also discovered.

Finally, scientists are launching new research projects as well. A Florida State University research is leading an effort to produce a comprehensive, international, comparative history of the Arctic region. A physical scientist in Svalbard plans to launch a rocket to gather atmospheric data in an effort to better understand the connection between the northern lights and disturbances to navigation systems and radio signals. The project is essential for developing warning systems to deal with these problems. Airplanes that fly over the Arctic can risk losing radio contact for several hours if the northern lights are active.

Know of another significant news story from November that you’d like to share? Reactions to one of the stories discussed here?  Post a comment-we’d love to hear from you!