If the large-scale ocean circulation is disturbed by processes altering heat and salinity in the Arctic Ocean, the consequences may be felt worldwide. The mechanism involved is the world-encompassing meridional overturning circulation (MOC).

Snow and the various forms of ice - the cryosphere - play different roles within the climate system. The two continental ice sheets of Antarctica and Greenland actively influence the global climate over time scales of millennia to millions of years, but may also have more rapid effects on, for example, sea level. Snow and sea ice, with their large areas but relatively small volumes, are connected to key interactions and feedbacks at global scales...

Snow and the various forms of ice - the cryosphere - play different roles within the climate system. The two continental ice sheets of Antarctica and Greenland actively influence the global climate over time scales of millennia to millions of years, but may also have more rapid effects on, for example, sea level. Snow and sea ice, with their large areas but relatively small volumes, are connected to key interactions and feedbacks at global scales...

There are major regional differences for the Arctic sea ice, with the strongest decline in ice extent observed for the Greenland Sea (10.6 per cent per decade). The smallest decreases of annual mean sea ice extent were found in the Arctic Ocean, the Canadian Archipelago and the Gulf of St. Lawrence. In the marginal Arctic seas off Siberia (the Kara, Laptev, East Siberian and Chukchi Seas) a slight negative, but not significant, trend in ice exten...

The global ocean circulation system will change under the strong influence of arctic warming.

Changes in sea levels resulting exclusively from changes in ocean density and circulation patterns, results of atmosphere-ocean general circulation models (AOGCM) for climate change scenario A1B (this scenario assumes future rapid demographic and economic growth, introduction of new and more efficient technologies, accompanied by a balanced use of all types of energy sources) show that there will be significant spatial variability, i.e., changes ...

Melting and warming will have consequences on ocean circulation. Additionally melting of inland glaciers and continental ice sheets on Greenland and Antarctica, and the thermal expansion of ocean waters are causing sea level rise.