Impact of global warming on the Antarctic mass balance and global sea level

Technical Report · Sun Mar 01 04:00:00 EST 1992

OSTI ID:7015115

Budd, W F; Simmonds, I

The onset of global warming from increasing greenhouse gases in the atmosphere can have a number of important different impacts on the Antarctic ice sheet. These include increasing basal melt of ice shelves, faster flow of the grounded ice, increased surface ablation in coastal regions, and increased precipitation over the interior. An analysis of these separate terms by ice sheet modeling indicates that the impact of increasing ice sheet flow rates on sea level does not become a dominant factor until 100--200 years after the realization of the warming. For the time period of the next 100 years the most important impact on sea level from the Antarctic mass balance can be expected to result from increasing precipitation minus evaporation balance over the grounded ice. The present Antarctic net accumulation and coastal ice flux each amount to about 2000 km3 yr-1, both of which on their own would equate to approximately 6 mm yr-1 of sea level change. The present rate of sea level rise of about 1.2 mm yr-1 is therefore equivalent to about 20% imbalance in the Antarctic mass fluxes. The magnitude of the changes to the Antarctic precipitation and evaporation have been studied by a series of General Circulation Model experiments, using a model which gives a reasonable simulation of the present Antarctic climate, including precipitation and evaporation.

• Research Organization: Melbourne Univ., Parkville (Australia)
• OSTI ID: 7015115
• Report Number(s): AD-P-007330/4/XAB
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
540120* -- Environment
Atmospheric-- Chemicals Monitoring & Transport-- (1990-)
540310 -- Environment
Aquatic-- Basic Studies-- (1990-)
ANTARCTIC REGIONS
CLIMATES
COASTAL REGIONS
ENVIRONMENTAL IMPACTS
EVAPORATION
FLOW RATE
GENERAL CIRCULATION MODELS
GLOBAL ASPECTS
GREENHOUSE GASES
ICE
ICE CAPS
LEVELS
MASS BALANCE
MATHEMATICAL MODELS
PHASE TRANSFORMATIONS
POLAR REGIONS
SEA LEVEL
SIMULATION
VARIATIONS