[[VIDEO.PLAYER||Greenland Ice Loss 2003-2013||The mass of the Greenland ice sheet has rapidly been declining over the last several years due to surface melting and iceberg calving. Research based on observations from NASA’s twin Gravity Recovery and Climate Experiment (GRACE) satellites indicates that between 2003 and 2013, Greenland shed approximately 280 gigatons of ice per year, causing global sea level to rise by 0.8 millimeters per year. These images, created with GRACE data, show changes in Greenland ice mass since 2003. Orange and red shades indicate areas that lost ice mass, while light blue shades indicate areas that gained ice mass. White indicates areas where there has been very little or no change in ice mass since 2003. In general, higher-elevation areas near the center of Greenland experienced little to no change, while lower-elevation and coastal areas experienced up to 3 meters of ice mass loss (dark red) over a 10-year period. The largest mass decreases of up to 30 centimeters per year occurred over southeastern Greenland.||/system/video_items/15_grace_greenland_2004_2013_720p.mp4||undefined||undefined||/system/resources/detail_files/21_grace_greenland_2004_2012_still_print.jpg||Greenland Ice Loss 2003-2013||Column-width||21||false||false]]

Since 2002, the twin satellites of GRACE have made a complete map of Earth’s gravitational field every 30 days. Gravity is determined by mass. While most of the planet’s mass — its land and core — doesn’t move much in 30 days, its water and ice do, causing Earth’s gravity to shift. By tracking these changes, GRACE and GRACE-FO can identify how much ice sheets and glaciers are shrinking.

GRACE data are used extensively to determine mass changes of the world’s land ice (ice sheets, icefields, ice caps and mountain glaciers). Land ice continually adds mass through precipitation and loses mass via meltwater runoff and calving of solid ice into the ocean. If losses are greater than gains, land ice loses mass, causing sea level to rise. Over the last decade or so, losses from land ice have been implicated in causing two-thirds of the observed rise in sea level.

Researchers seek to further scientific understanding of ice-sheet dynamics and land-ice response to changes in atmospheric conditions and how these processes influence rates of sea-level change. GRACE data also provide information about seasonal and sub-seasonal variations in water transport between the continental land masses and oceans – of which the cryosphere (Earth’s frozen places) is an important component.

Data from the GRACE satellites show that ice sheets in both Antarctica and Greenland are losing mass. The continent of Antarctica has been losing about 118 gigatons of ice per year since 2002, while the Greenland ice sheet has been losing an estimated 281 gigatons per year. One gigaton equals a billion metric tons.

"Earth is losing a huge amount of ice to the ocean annually, and these new results will help us answer important questions in terms of both sea rise and how the planet's cold regions are responding to global change," said onetime University of Colorado Boulder physics professor John Wahr, who helped lead a study of the ice between 2003 and 2010. "The strength of GRACE is it sees all the mass in the system, even though its resolution is not high enough to allow us to determine separate contributions from each individual glacier."

[[VIDEO.PLAYER||Antarctic Mass Change from GRACE – January 2004 - June 2014||These animations show the change in the mass of the Antarctic Ice Sheet between January 2004 and June 2014 as measured by the pair of GRACE satellites. The 1-arc-deg NASA GSFC mascon solution data was resampled to a 5130 x 5130 data array using Kriging interpolation. A color scale was applied where blue values indicate an increase in the ice sheet mass while red shades indicate a decrease. In addition, a graph overlay shows the running total of the accumulated mass change in gigatons.||/system/video_items/16_GRACE_Antarctica_AIS_1080p.mp4||undefined||undefined||/system/resources/detail_files/22_GRACE_Antarctica_p30.01146_print.jpg|| These animations show the change in the mass of the Antarctic Ice Sheet between January 2004 and June 2014 as measured by the pair of GRACE satellites. The 1-arc-deg NASA GSFC mascon solution data was resampled to a 5130 x 5130 data array using Kriging interpolation. A color scale was applied where blue values indicate an increase in the ice sheet mass while red shades indicate a decrease. In addition, a graph overlay shows the running total of the accumulated mass change in gigatons.||Column-width||22||false||false]]

You Might Also Like