Ice sheet change is expected to be a "slow" climate feedback. How rapidly ice sheets can disintegrate is one of the most uncertain and imporant climate issues. The dominant physical process causing ice sheet disintegration may be absorption of heat by the ocean (due to an increasing greenhouse effect), resulting melting of ice shelves, and thus an increased rate of discharge of ice from the ice sheet to the ocean. Once this process gets well underway, it may be difficult to prevent accelerating ice sheet disintegration under its own impetus ( http://pubs.giss.nasa.gov/docs/2005/2005_Hansen.pdf).
The figures above show the rate of mass loss from the Greenland and Antarctic ice sheets, based on updates of Rignot et al. (2011) and Wiese, et al. (2019), and NASA Global Climate Change: Vital Signs of th Planet web page (Data through January 2021).
Approximate data read off from Rignot et al. (2019) of Fig.3A Antarctica and best doubling fit for 1979-2014 (end of the year).
E. Rignot et al. (2011) "Acceleration of the contribution of the Greenland and Antarctic ice sheets to sea level rise", GRL, 38, L05503 (5 pp.)
E. Rignot et al. (2019) "Four decades of Antarctic Ice Sheet mass balance from 1979-2017", PNAS, doi:10.1073/pnas.1812883116.
Wiese, D. N., D.-N. Yuan, C. Boening, F. W. Landerer, and M. M. Watkins (2019) JPL GRACE and GRACE-FO Mascon Ocean, Ice, and Hydrology Equivalent Water Height RL06M CRI Filtered Version 2.0, Ver. 2.0, PO.DAAC, CA, USA. Dataset accessed [2021-03-17] at http://dx.doi.org/10.5067/TEMSC-3MJ62.
Our Essay: "Update of Greenlnad Ice Sheet Mass Loss: Exponential?" (2012/12/26)