Greenland Bedrock Topographic Map
Created using ETOPO1 Global Relief Model bedrock version
www.ngdc.noaa.gov/mgg/global/global.html
Greenland holds about 10% of the world's ice. If it all melts, sea level would rise 6-7 meters (20+ feet).
Greenland ice growth began almost 10 million years ago and reached roughly current levels more than 2 million years ago.
Over the past 2 million years, ice sheets repeatedly grew and shrank across Canada, the northern US, most of Siberia, and most of northern Europe. We call these periods Ice Ages. At their peak, these ice sheets held twice as much ice as Antarctica does today. (See Hansen 0913 on Overviews page for a geologically recent history of sea level.) From 20 to 8 thousand years ago (KYa), those ice sheets vanished, raising sea levels by 1 meter per century, including 1.5 meter per century from 15 to 8 KYa.
Some researchers (Robinson, Koenig) have made the case that current CO2 levels are incompatible with continued existence of the Greenland ice cap or sheet, especially once temperatures increase to those associated with past CO2 levels this high (~ 400 ppm).
Perhaps 20% of Greenland's ice is grounded below sea level. But most of that is inland sea, not connected to the ocean. Maybe 5% to the ocean.
Contribution of the Greenland Ice Sheet to Sea Level over the Next Millennium 0619.rtf
5-33 cm by 2100 and 56-720 cm by 3000, depending on emissions scenario and other factors. Panel A is about temperature increase at Greenland and Panel B is about sea level rise as a result for Greenland. RCP 8.5 is the fastest global temperature rise modeled and RCP 2.6 the slowest.
Below that (top 4) are maps for the year 3000 of ice-freee areas now and under under the scenarios.
Fig. 2 Observed 2008 state and simulations of the Greenland Ice Sheet at year 3000.(A) Observed 2008 ice extent (53). (B to D) Likelihood (percentiles) of ice cover as percentage of the ensemble simulations with nonzero ice thickness. Likelihoods less than the 16th percentile are masked. (E) Multi-year composite of observed surface speeds (61). (F to H) Surface speeds from the control simulation. Basin names shown in (A) in clockwise order are southwest (SW), central-west (CW), northwest (NW), north (NO), northeast (NE), and southeast (SE). RCP 2.6 (B and F), RCP 4.5 (C and G), and RCP 8.5 (D and H). Topography in meters above sea level (m a.s.l.) [(A) to (H)].
An Arctic Ice Cap’s Shockingly Rapid Slide into the Sea 0115.rtf
Svalbard / Spitzbergen actually
Section Map: Ice