Scientists Alexander Kolesnik (L) and Daria Petrova examine mud and sea life dredged up from the bottom of the Bering Sea on board the Russian research vessel Professor Khromov August 29, 2009. A joint U.S.-Russian oceanographic expedition, the Russian-American Long-term Census of the Arctic (RUSALCA), is studying the impact of climate change on the waters from Alaska's coast to Russia's eastern tip. Picture taken August 29, 2009. To match feature USA-RUSSIA/ENVIRONMENT REUTERS/Jeffrey Jones (RUSSIA SCI TECH ENVIRONMENT)