[llccbb]

0.3 mm/yr * 26 yr = 7.8 mm

Antarctica's contribution to sea level rise per year is fairly small. The largest portion comes from loss of land-ice like mountain glaciers and snow pack. Mass loss from the Greenland Ice Sheet is also substantial, contributing about 2.7 mm/yr to sea level change. Groundwater withdrawal is a measurable component of modern sea level rise. Aside from these mass-transfer mechanisms, there is also ocean warming (water generally expands as it get warmer) and salinity changes that don't affect the amount of water in the oceans, but do affect its volume. Loss of sea ice (which floats on top of water and is not supported from below by solid earth) does not contribute to sea level change, as the sea ice is already displacing an amount of water equal to the amount of ice doing the displacing.

That 2015 Jay Zwally paper should not be taken as truth, as there are substantial reasons to doubt the impact of the findings. In that paper Zwally uses a set of satellite laser altimeters operating over different epochs and neglects to co-register the different platforms in an intelligent way. There was actually major hubbub around that paper and most glaciologists recognize the claim that "Antarctica is gaining mass" is probably incorrect.[0] Zwally has a pretty big ego and was happy to get the publicity anyways.

[0] https://www.scientificamerican.com/article/what-to-believe-i...

[mkempe]

Greenland does not contribute that much to global sea-level rise: "The cumulative ice loss from Greenland from 1992 to 2015 was 3,600 Gt and contributed to global sea level rise by approximately 10 mm" -- that's less than 0.5 mm/year. [1]

Where did you get that Greenland contribution rate?

[1] https://www.eea.europa.eu/data-and-maps/indicators/greenland...