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Really wild guess, but if Antarctica isn't the source of the rising ocean wouldn't it make sense to consider the Arctic as source?

by tete 11y ago

cjensen 11y ago
Just to be clear: when floating sea ice melts, it does not change the ocean level. Usually land-based Arctic ice is enumerated as Greenland and other glaciers.
- schiffern 11y ago
  >Just to be clear: when floating sea ice melts, it does not change the ocean level. Unless you consider thermal expansion due to albedo change. Sea ice is one of the whitest surfaces on the planet, and open water one of the darkest.
- tete 11y ago
  I don't know how much and a quick Google (and DuckDuckGo) didn't give me any results, but since you mention it. The arctic ice also partly covers land, not only of Greenland I think. Do you maybe know how much that amounts to? And slightly related it's not pure ice. It contains all sorts of things. Again, not sure how much that is, but curious to learn if anyone has any numbers and maybe even is able to put them into relation.
deleted 11y ago
[deleted]
ovis 11y ago
Even prior to this, it was thought that Antarctica was only a small fraction sea level rise at present. Thermal expansion of sea water, melting mountain glaciers, and Greenland appear to contribute far more. The latest IPCC report (Chapter 13, table 13.1) has some good numbers representing the best we knew a couple of years ago. The impact of this study is that the small mass loss attributed to Antarctica may be a small mass gain.
- epistasis 11y ago
  I was just in the process of summarizing that table, thanks for bringing it up. The QZ article does not really place this finding in context of what else is going on and what is already known. The current breakdown from IPCC's 5th Assessment Report: 1.1 [0.8 to 1.4] mm per year -- thermal ocean expansion 0.76 [0.39 to 1.13] mm per year -- glacial melt 0.33 [0.25 to 0.41] mm per year -- Greenland ice sheet melt 0.27 [0.16 to 0.38] mm per year -- Antarctic ice sheet melt 0.38 [0.26 to 0.49] mm per year -- land water storage change Sum: 2.8 mm/year Observed: 3.2 mm/year [1] [2] As usual, Wikipedia has good entry level summaries [3] of the high-level info, for those of us that want to get right to the meat. [1] http://imgur.com/vadnlXJ http://imgur.com/vadnlXJ [2] http://www.climatechange2013.org/images/uploads/WGIAR5_WGI-12Doc2b_FinalDraft_Chapter13.pdf http://www.climatechange2013.org/images/uploads/WGIAR5_WGI-1... [3] https://en.wikipedia.org/wiki/Sea_level_rise https://en.wikipedia.org/wiki/Sea_level_rise
knowaveragejoe 11y ago
Antartica is a source of water causing the oceans to rise. This paper demonstrates that snow is offsetting that loss in terms of total mass of Antarctica.

Really wild guess, but if Antarctica isn't the source of the rising ocean wouldn't it make sense to consider the Arctic as source?

by tete 11y ago

Really wild guess, but if Antarctica isn't the source of the rising ocean wouldn't it make sense to consider the Arctic as source?

cjensen 11y ago

Just to be clear: when floating sea ice melts, it does not change the ocean level. Usually land-based Arctic ice is enumerated as Greenland and other glaciers.

schiffern 11y ago
>Just to be clear: when floating sea ice melts, it does not change the ocean level. Unless you consider thermal expansion due to albedo change. Sea ice is one of the whitest surfaces on the planet, and open water one of the darkest.
tete 11y ago
I don't know how much and a quick Google (and DuckDuckGo) didn't give me any results, but since you mention it. The arctic ice also partly covers land, not only of Greenland I think. Do you maybe know how much that amounts to? And slightly related it's not pure ice. It contains all sorts of things. Again, not sure how much that is, but curious to learn if anyone has any numbers and maybe even is able to put them into relation.

deleted 11y ago

[deleted]

ovis 11y ago

Even prior to this, it was thought that Antarctica was only a small fraction sea level rise at present. Thermal expansion of sea water, melting mountain glaciers, and Greenland appear to contribute far more. The latest IPCC report (Chapter 13, table 13.1) has some good numbers representing the best we knew a couple of years ago. The impact of this study is that the small mass loss attributed to Antarctica may be a small mass gain.

epistasis 11y ago
I was just in the process of summarizing that table, thanks for bringing it up. The QZ article does not really place this finding in context of what else is going on and what is already known. The current breakdown from IPCC's 5th Assessment Report: 1.1 [0.8 to 1.4] mm per year -- thermal ocean expansion 0.76 [0.39 to 1.13] mm per year -- glacial melt 0.33 [0.25 to 0.41] mm per year -- Greenland ice sheet melt 0.27 [0.16 to 0.38] mm per year -- Antarctic ice sheet melt 0.38 [0.26 to 0.49] mm per year -- land water storage change Sum: 2.8 mm/year Observed: 3.2 mm/year [1] [2] As usual, Wikipedia has good entry level summaries [3] of the high-level info, for those of us that want to get right to the meat. [1] http://imgur.com/vadnlXJ http://imgur.com/vadnlXJ [2] http://www.climatechange2013.org/images/uploads/WGIAR5_WGI-12Doc2b_FinalDraft_Chapter13.pdf http://www.climatechange2013.org/images/uploads/WGIAR5_WGI-1... [3] https://en.wikipedia.org/wiki/Sea_level_rise https://en.wikipedia.org/wiki/Sea_level_rise

knowaveragejoe 11y ago

Antartica is a source of water causing the oceans to rise. This paper demonstrates that snow is offsetting that loss in terms of total mass of Antarctica.