Corrected ICESat altimetry data, surface mass balance, and firn elevation change on Antarctic ice shelves


Autoria(s): Pritchard, Hamish; Ligtenberg, Stefan R M; Fricker, Helen; van den Broeke, Michiel R; Vaughan, David G; Padman, Laurie
Cobertura

MEDIAN LATITUDE: -71.731111 * MEDIAN LONGITUDE: -173.453333 * SOUTH-BOUND LATITUDE: -80.800000 * WEST-BOUND LONGITUDE: 53.000000 * NORTH-BOUND LATITUDE: -66.300000 * EAST-BOUND LONGITUDE: -5.900000

Data(s)

14/02/2012

Resumo

Accurate prediction of global sea-level rise requires that we understand the cause of recent, widespread and intensifying glacier acceleration along Antarctic ice-sheet coastal margins. Floating ice shelves buttress the flow of grounded tributary glaciers and their thickness and extent are particularly susceptible to changes in both climate and ocean forcing. Recent ice-shelf collapse led to retreat and acceleration of several glaciers on the Antarctic Peninsula. However, the extent and magnitude of ice-shelf thickness change, its causes and its link to glacier flow rate are so poorly understood that its influence on the future of the ice sheets cannot yet be predicted. Here we use satellite laser altimetry and modelling of the surface firn layer to reveal for the first time the circum-Antarctic pattern of ice-shelf thinning through increased basal melt. We deduce that this increased melt is the primary driver of Antarctic ice-sheet loss, through a reduction in buttressing of the adjacent ice sheet that has led to accelerated glacier flow. The highest thinning rates (~7 m/a) occur where warm water at depth can access thick ice shelves via submarine troughs crossing the continental shelf. Wind forcing could explain the dominant patterns of both basal melting and the surface melting and collapse of Antarctic ice shelves, through ocean upwelling in the Amundsen and Bellingshausen Seas and atmospheric warming on the Antarctic Peninsula. This implies that climate forcing through changing winds influences Antarctic Ice Sheet mass balance, and hence global sea-level, on annual to decadal timescales.

Formato

application/zip, 2 datasets

Identificador

https://doi.pangaea.de/10.1594/PANGAEA.775984

doi:10.1594/PANGAEA.775984

Idioma(s)

en

Publicador

PANGAEA

Relação

Pritchard, Hamish; Ligtenberg, Stefan R M; Fricker, Helen; van den Broeke, Michiel R; Vaughan, David G; Padman, Laurie (2012): Antarctic ice sheet loss driven by basal melting of ice shelves. (PDI-1401), Nature, submitted

Direitos

CC-BY: Creative Commons Attribution 3.0 Unported

Access constraints: unrestricted

Palavras-Chave #Area; Area/locality; File name; File size; ice2sea; Latitude; LATITUDE; Longitude; LONGITUDE; maximum, relative to the South Pole; minimum, relative to the South Pole; Polar stereographic projection, X; Polar stereographic projection, Y; Polar stereo X; Polar stereo Y; shapefiles, zipped; Uniform resource locator/link to file; URL file
Tipo

Dataset