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There's a NASA study from 2015 that concludes that mass gains of the Antarctic ice sheet are greater than the losses: https://www.nasa.gov/feature/goddard/nasa

There's a NASA study from 2015 that concludes that mass gains of the Antarctic ice sheet are greater than the losses: https://www.nasa.gov/feature/goddard/nasa-study-mass-gains-of-antarctic-ice-sheet-greater-than-losses https://www.nasa.gov/feature/goddard/nasa-study-mass-gains-o...

sambull 9y ago
Zwally's study is in-line with the GRACE data, and loss of land ice mass. "According to the new analysis of satellite data, the Antarctic ice sheet showed a net gain of 112 billion tons of ice a year from 1992 to 2001. That net gain slowed to 82 billion tons of ice per year between 2003 and 2008." GRACE shows acceleration since 2008. Zwally's study uses data from 1992-2001, 2003-2008. And is in-line with the net-gain slowing down in his data-set.
mturmon 9y ago
This misleading comment cherry picks one particular study to suggest a conclusion that is probably not true. The commenter started out talking about sea ice, and when (rightly) that was noted to be irrelevant, switched to a different press release. The linked study (Zwally et al.) uses satellite radar altimetry (ICESat) to measure height of Antarctic ice, and thereby quantify mass losses. Other studies use satellite-derived gravity (GRACE) to get more directly at mass changes. They conflict. One possible reason (among several) for the discrepancy is that the overall height of Antarctica is also changing as it rebounds from ice loss in the distant past, i.e., some of the height increase seen by Zwally et al. is due not to ice increases, but to inter-ice-age rebound of the continent beneath the ice. More: https://www.washingtonpost.com/news/energy-environment/wp/2015/11/05/a-controversial-nasa-study-says-antarctica-is-gaining-ice-heres-why-you-should-stay-skeptical/?utm_term=.86898c732394 https://www.washingtonpost.com/news/energy-environment/wp/20...

sambull 9y ago

Zwally's study is in-line with the GRACE data, and loss of land ice mass. "According to the new analysis of satellite data, the Antarctic ice sheet showed a net gain of 112 billion tons of ice a year from 1992 to 2001. That net gain slowed to 82 billion tons of ice per year between 2003 and 2008." GRACE shows acceleration since 2008. Zwally's study uses data from 1992-2001, 2003-2008. And is in-line with the net-gain slowing down in his data-set.

mturmon 9y ago

This misleading comment cherry picks one particular study to suggest a conclusion that is probably not true. The commenter started out talking about sea ice, and when (rightly) that was noted to be irrelevant, switched to a different press release. The linked study (Zwally et al.) uses satellite radar altimetry (ICESat) to measure height of Antarctic ice, and thereby quantify mass losses. Other studies use satellite-derived gravity (GRACE) to get more directly at mass changes. They conflict. One possible reason (among several) for the discrepancy is that the overall height of Antarctica is also changing as it rebounds from ice loss in the distant past, i.e., some of the height increase seen by Zwally et al. is due not to ice increases, but to inter-ice-age rebound of the continent beneath the ice. More: https://www.washingtonpost.com/news/energy-environment/wp/2015/11/05/a-controversial-nasa-study-says-antarctica-is-gaining-ice-heres-why-you-should-stay-skeptical/?utm_term=.86898c732394 https://www.washingtonpost.com/news/energy-environment/wp/20...