How does rising atmospheric CO2 affect marine organisms?

Click to locate material archived on our website by topic

East Antarctica's Role in Global Sea Level Change
Mackintosh, A., White, D., Fink, D., Gore, D.B., Pickard, J. and Fanning, P.C. 2007. Exposure ages from mountain dipsticks in Mac. Robertson Land, East Antarctica, indicate little change in ice-sheet thickness since the Last Glacial Maximum. Geology 35: 551-554.

What was done
The authors derived altitudinal transects of 10Be and 26Al exposure ages across the Framnes Mountains in Mac. Robertson Land that allowed them to calculate the magnitude and timing of East Antarctic Ice Sheet (EAIS) retreat following the Last Glacial Maximum.

What was learned
The six researchers determined that (1) reduction in ice sheet volume in Mac. Robertson Land made an insignificant contribution to global sea-level rise between thirteen and seven thousand years ago, (2) the present ice-sheet profile was attained about seven thousand years ago, and (3) the EAIS in Mac. Robertson Land has not undergone major retreat during the past seven thousand years.

What it means
With respect to the past, Mackintosh et al. say their data suggest that "the reduction in EAIS volume since the Last Glacial Maximum was smaller than that indicated by contemporary ice-sheet models and added little meltwater to the global oceans." With respect to the present, they say their results are "consistent with satellite-based radar altimetry measurements that indicate that the EAIS interior has grown [our italics] since 1992 in response to an increase in snowfall (Davis et al., 2005)." With respect to the future, therefore, we could logically conclude that a continuation of earth's Current Warm Period will not result in any increase in sea level due to phenomena occurring in East Antarctica.

Davis, C.H., Li, Y., McConnell, J.R., Frey, M.M. and Hanna, E. 2005. Snowfall-driven growth in East Antarctic Ice Sheet mitigates recent sea-level rise. Science 308: 1898-1901.

Reviewed 23 April 2008