Ice core evidence for Antarctic sea ice decline since the 1950s.
The instrumental record of Antarctic sea ice in recent decades does not reveal a clear signature of warming despite observational evidence from coastal Antarctica. Here we report a significant correlation (P < 0.002) between methanesulphonic acid (MSA) concentrations from a Law Dome ice core and 22 years of satellite-derived sea ice extent (SIE) for the 80 degrees E to 140 degrees E sector. Applying this instrumental calibration to longer term MSA data (1841 to 1995 A.D.) suggests that there has been a 20% decline in SIE since about 1950. The decline is not uniform, showing large cyclical variations, with periods of about 11 years, that confuse trend detection over the relatively short satellite era.
Curran
Mark A J
MA
Department of the Environment and Heritage, Australian Antarctic Division, and Antarctic Climate and Ecosystem Cooperative Research Centre, Private Bag 80, Hobart, Tasmania 7001, Australia. mark.curran@utas.edu.au
van Ommen
Tas D
TD
Morgan
Vin I
VI
Phillips
Katrina L
KL
Palmer
Anne S
AS