Mountain glaciers and ice caps around Antarctica make a large sea-level rise contribution

Abstract

[1] The Intergovernmental Panel on Climate Change (IPCC) estimates that the sum of all contributions to sea-level rise for the period 1961-2004 was 1.1 ± 0.5 mm a-1, leaving 0.7 ± 0.7 of the 1.8 ± 0.5 mm a-1 observed sea-level rise unexplained. Here, we compute the global surface mass balance of all mountain glaciers and ice caps (MG&IC), and find that part of this much-discussed gap can be attributed to a larger contribution than previously assumed from mass loss of MG&IC, especially those around the Antarctic Peninsula. We estimate global surface mass loss of all MG&IC as 0.79 ± 0.34 mm a-1 sea-level equivalent (SLE) compared to IPCC's 0.50 ± 0.18 mm a-1. The Antarctic MG&IC contributed 28% of the global estimate due to exceptional warming around the Antarctic Peninsula and high sensitivities to temperature similar to those we find in Iceland, Patagonia and Alaska. Copyright 2009 by the American Geophysical Union.