Glaciers and ice caps

Greenland ice sheet

Antarctic ice sheet

glaciers and ice caps have contributed to sea level rise (ice caps do not include contributions from the Greenland and Antarctic ice sheets). (See Table SPM-1.) {4.6, 4.7,

New data since the TAR now show that losses from the ice sheets of

Greenland and Antarctic outlet glaciers, which drain ice from the interior of the ice sheets.
... ledovcù v okrajových oblastech Grónska a Antarktidy

increased ice sheet mass loss has often followed thinning, reduction or loss of ice shelves or loss of floating glacier tongues.

Satellite data since 1978 show that annual average Arctic sea ice extent

Antarctic sea ice extent continues to show inter-annual variability

Global average sea level in the last interglacial period (about 125,000 years ago) was likely 4 to 6 m higher than during the 20th century, mainly due to the retreat of polar ice.

Greenland ice sheet and other Arctic ice fields likely contributed no more than 4 m of the observed sea level rise.

125,000 years ago, when paleoclimatic information suggests reductions of polar land ice extent

However, net loss of ice mass could occur if dynamical ice discharge dominates the ice sheet mass balance.

Contraction of the Greenland ice sheet is projected to continue to contribute to sea level rise after 2100. Current models suggest ice mass losses increase with temperature more rapidly than gains due to precipitation and that the surface mass balance becomes negative at a global average warming (relative to pre-industrial values) in excess of 1.9 to 4.6°C. If a negative surface mass balance were sustained for millennia, that would lead to virtually complete elimination of the Greenland ice sheet and a resulting contribution to sea level rise of about 7 m. The corresponding future temperatures in Greenland are comparable to those inferred for the last interglacial period 125,000 years ago, when paleoclimatic information suggests reductions of polar land.

Current global model studies project that the Antarctic ice sheet will remain too cold for widespread surface melting and is expected to gain in mass due to increased snowfall. However, net loss of ice mass could occur if dynamical ice discharge dominates the ice sheet mass balance.