Stunning data from the NASA Earth Observatory’s IceBridge program indicates that “Greenland’s Jakobshavn glacier has the potential to influence sea level rise more than any other single feature in the Northern Hemisphere.”
Detailed mapping of the bedrock below the fastest flowing glacier in the world revealed that a canyon the width and depth of the Grand Canyon funnels melting ice out to the Atlantic Ocean at a rate of 15 kilometers per year. Understanding the dynamics of glacial beds allows researchers to better predict the rates of ice-loading to the ocean, which in turn allows them to refine estimates of future sea level rise.
Earth Observatory scientists hope to spin up their sea level rise projections based on this and other IceBridge evidence in time for the IPCC’s Fifth Assessment Report, due out in 2014. We’re guessing that, based on NASA’s Greenland and Antarctica research and other developments, IPCC will revise the “0.18 to 0.59 meter by 2100” (from the Fourth Assessment Report) upward for 5AR. Will it top the “1 meter by 2100” that is the current general consensus? We’re on pins and needles…are you?