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Variability in the surface temperature and melt extent of the Greenland ice sheet from MODIS
Author(s) -
Hall Dorothy K.,
Comiso Josefino C.,
DiGirolamo Nicolo E.,
Shuman Christopher A.,
Box Jason E.,
Koenig Lora S.
Publication year - 2013
Publication title -
geophysical research letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.007
H-Index - 273
eISSN - 1944-8007
pISSN - 0094-8276
DOI - 10.1002/grl.50240
Subject(s) - greenland ice sheet , ice sheet , climatology , groenlandia , geology , cryosphere , future sea level , glacier , moderate resolution imaging spectroradiometer , ice sheet model , ice stream , environmental science , satellite , oceanography , sea ice , geomorphology , aerospace engineering , engineering
Satellite‐derived moderate‐resolution imaging spectroradiometer (MODIS) ice‐surface temperature (IST) of the Greenland ice sheet shows a positive trend and two major melt events from 2000 to present. IST increased by ~0.55 ± 0.44°C/decade, with the greatest increase (~0.95 ± 0.44°C/decade) found in northwestern Greenland where coastal temperatures and mass loss are also increasing and outlet glaciers are accelerating. IST shows the highest rates of increase during summer (~1.35 ± 0.47°C/decade) and winter (~1.30 ± 1.53°C/decade), followed by spring (~0.60 ± 0.98°C/decade). In contrast, a decrease in IST was found in the autumn (~−1.49 ± 1.20°C/decade). The IST trends in this work are not statistically significant with the exception of the trend in northwestern Greenland. Major surface melt (covering 80% or more of the ice sheet) occurred during the 2002 and 2012 melt seasons where clear‐sky measurements show a maximum melt of ~87% and ~95% of the ice sheet surface, respectively. In 2002, most of the extraordinary melt was ephemeral, whereas in 2012 the ice sheet not only experienced more total melt, but melt was more persistent, and the 2012 summer was the warmest in the MODIS record (−6.38 ± 3.98°C). Our data show that major melt events may not be particularly rare during the present period of ice sheet warming.