Overture -- Global warming effects on the Arctic and Sub-Arctic Seas -- The case for global warming in the Arctic -- A coherency between the North Atlantic temperature nonlinear trend, the eastern Arctic ice extent drift and change in the atmospheric circulation regimes over the northern Eurasia -- Mesoscale atmospheric vortices in the Okhotsk and Bering Seas: results of satellite multisensor study -- Recent sea ice ecosystem in the Arctic Ocean: a review -- The effects of irradiance and nutrient supply on the productivity of Arctic waters: a perspective on climate change -- Production of phytoplankton in the Arctic Seas and its response on recent warming -- Reconstruction of oceanic circulation using mineralogical and isotopical (Nd/Pb) signatures of deep sea sediments: the case study of the northern North Atlantic and some perspectives for the Arctic -- Observing and interpreting the seasonal variability of the oceanographic fluxes passing through Lancaster Sound of the Canadian Arctic Archipelago -- River flux of dissolved organic carbon (DOC) and particulate organic carbon (POC) to the Arctic Ocean: what are the consequences of the global changes? -- Mechanisms of the recent sea ice decay in the Arctic Ocean related to the Pacific-to-Atlantic pathway -- Frontal Zones in the Norwegian, Greenland, Barents and Bering Seas -- How do the very small-sized aquatic microbes influence the very large-scale biogeochemical cycles? -- Social, economic, legal and political issues of the Russian Arctic -- Two US programs during IPY. The current warming trends in the Arctic may shove the Arctic system into a seasonally ice-free state not seen for more than one million years. The melting is accelerating, and researchers were unable to identify natural processes that might slow the deicing of the Arctic. Such substantial additional melting of Arctic and Antarctic glaciers and ice sheets would raise the sea level worldwide, flooding the coastal areas where many of the world's population lives. Studies, led by scientists at the National Center for Atmospheric Research (NCAR) and the University of Arizona, show that greenhouse gas increases over the next century could warm the Arctic by 3-5°C in summertime. Thus, Arctic summers by 2100 may be as warm as they were nearly 130,000 years ago, when sea levels eventually rose up to 6 m higher than today.