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In 2014 Antarctic sea ice reached a record maximum: https://www.nasa.gov/content/goddard/antarctic-sea-ice-reaches-new-record-maximum https://www.nasa.gov/cont

In 2014 Antarctic sea ice reached a record maximum: https://www.nasa.gov/content/goddard/antarctic-sea-ice-reaches-new-record-maximum https://www.nasa.gov/content/goddard/antarctic-sea-ice-reach... But now in 2017 we're talking about continent-wide collapse?

sambull 9y ago
Sea ice comes and goes. Land ice is much more important. There is an acceleration on land ice loss. https://climate.nasa.gov/vital-signs/land-ice/ https://climate.nasa.gov/vital-signs/land-ice/
- tmpdude01 9y ago
  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...
Chronos 9y ago
That's a record extent, not a record volume. Volume is how much ice there is. Extent without volume means the ice is more spread out, i.e. thinner.
wcoenen 9y ago
The way I understood it, the article is about glaciers and ice shelves, not about antarctic sea ice extent which is largely driven by wind patterns. The more northward winds, the more sea ice. Incidentally, antarctic sea ice extent did go from record highs 3 years ago to record lows this year. http://edition.cnn.com/2017/02/16/world/antarctica-sea-ice-record-low/index.html http://edition.cnn.com/2017/02/16/world/antarctica-sea-ice-r...
- jtbayly 9y ago
  Second paragraph from the 2015 study linked above makes clear it is talking about land, not sea ice: "The research challenges the conclusions of other studies, including the Intergovernmental Panel on Climate Change’s (IPCC) 2013 report, which says that Antarctica is overall losing land ice."

sambull 9y ago

Sea ice comes and goes. Land ice is much more important. There is an acceleration on land ice loss. https://climate.nasa.gov/vital-signs/land-ice/ https://climate.nasa.gov/vital-signs/land-ice/

tmpdude01 9y ago
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...

Chronos 9y ago

That's a record extent, not a record volume. Volume is how much ice there is. Extent without volume means the ice is more spread out, i.e. thinner.

wcoenen 9y ago

The way I understood it, the article is about glaciers and ice shelves, not about antarctic sea ice extent which is largely driven by wind patterns. The more northward winds, the more sea ice. Incidentally, antarctic sea ice extent did go from record highs 3 years ago to record lows this year. http://edition.cnn.com/2017/02/16/world/antarctica-sea-ice-record-low/index.html http://edition.cnn.com/2017/02/16/world/antarctica-sea-ice-r...

jtbayly 9y ago
Second paragraph from the 2015 study linked above makes clear it is talking about land, not sea ice: "The research challenges the conclusions of other studies, including the Intergovernmental Panel on Climate Change’s (IPCC) 2013 report, which says that Antarctica is overall losing land ice."