W. M. Connolley
British Antarctic Survey, Natural Environment Research Council,
High Cross, Madingley road, Cambridge, CB3 OET
Phone: (01223) 251479. Fax: (01223) 62616. Email: wmc@bas.ac.uk
Fresh water input to the Antarctic continent by precipitation is estimated at 2 x 10^15 kg/year and is roughly matched by loss of ice through iceberg calving and basal melting of iceshelves. If climate change causes a change in the precipitation over Antarctica this could have an impact on sea-level rise predictions, since the inflow (precipitation) can change far more rapidly that the outflow (glacial calving).
The UK Met Office has recently completed a set of transient climate-change experiments using a full coupled atmosphere-deep-ocean-sea-ice model. I use these runs to investigate possible changes in snow accumulation over Antarctica over the next 50 to 100 years. A major question is whether the accumulation will increase in step with temperature rises as has been generally assumed, or whether associated changes in the circulation patterns have a larger impact. I also compare the decadal-scale variability in the control and anomaly runs in order to assess the significance of the changes in precipitation. Finally, I consider the effects of these changes on sea level.