An article by Dr Jeff Masters, PhD meterologist and founder of the Weather Underground website. Dr. Jeff Masters' WunderBlog : The Heat is on in Greenland: Support the Dark Snow Project | Weather Underground
Figure 2. Monthly changes in the total mass (in Gigatonnes) of the Greenland ice sheet estimated from GRACE satellite measurements between March 2002 - July 2013. The blue and orange asterisks denote April and July values, respectively. Note that the decline in ice mass lost from Greenland is not a straight line--it is exponential, meaning that in general, more ice loss is lost each year than in the previous year. However, the mass loss during the 2013 summer melt season was probably smaller than during 2012, said the 2013 Arctic Report Card.
Saving Greenland's Ice Sheet is Imperative
Human-caused global warming has set in motion an unstoppable slow-motion collapse of the glaciers in West Antarctica capable of raising global sea level by 4 feet (1.2 meters) in a few hundred years, said NASA in a May 2014 press release. What's more, one of the glaciers involved, the Thwaites Glacier, acts as a linchpin on the rest of the ice sheet, which contains enough ice to cause a total of 10 to 13 feet (3 to 4 meters) of global sea level rise over a period of centuries. This unstoppable collapse makes saving Greenland "absolutely essential", said glaciologist Richard Alley in a May 2014 interview in Mother Jones. Greenland's ice sheet holds enough water to raise global sea levels by 7.36 meters (24.15 feet) were it all to melt, and civilization would be hard-pressed to deal with 10 - 13 feet of sea level rise from West Antarctica, let alone another 20+ feet from Greenland. "If we've committed to 3.3 meters (10.8') from West Antarctica, we haven't committed to losing Greenland, we haven't committed to losing most of East Antarctica," said Alley. "Those are still out there for us. And if anything, this new news just makes our decisions more important, and more powerful." Unfortunately, the Greenland Ice Sheet is much more vulnerable to melting than previously thought, found a May 2014 study by Morlighem et al., Deeply incised submarine glacial valleys beneath the Greenland ice sheet. The researchers found that widespread ice-covered valleys extend much deeper below sea level and farther inland than previously thought, and would likely melt significantly from steadily warming waters lapping at Greenland's shores.
Support for the Dark Snow Hypothesis
Observational evidence for the Dark Snow project's hypothesis that upwind forest fires might darken the Greenland Ice Sheet and cause significant melting was provided by a May 2014 paper by Keegan et al., Climate change and forest fires synergistically drive widespread melt events of the Greenland Ice Sheet. Their ice core study found that black carbon from forest fires helped caused a rare, near-ice-sheet-wide surface melt event that melted 97% of Greenland's surface on July 11 - 12 2012, and a similar event in 1889. Since Arctic temperatures and the frequency of forest fires are both expected to rise with climate change, the results suggest that widespread melt events on the Greenland Ice Sheet may begin to occur almost annually by the end of century.
Another factor contributing to a darker Greenland Ice Sheet and more melting may be additional wind-blown dust landing on the ice, according to a June 2014 study, Contribution of light-absorbing impurities in snow to Greenland's darkening since 2009. In an interview with ClimateWire, lead author Marie Dumont of France's meteorological agency said, "Our hypothesis is that now that seasonal snow cover in the Arctic is retreating earlier than before, and bare soil is available earlier in the Spring for dust transport."
Figure 2. Monthly changes in the total mass (in Gigatonnes) of the Greenland ice sheet estimated from GRACE satellite measurements between March 2002 - July 2013. The blue and orange asterisks denote April and July values, respectively. Note that the decline in ice mass lost from Greenland is not a straight line--it is exponential, meaning that in general, more ice loss is lost each year than in the previous year. However, the mass loss during the 2013 summer melt season was probably smaller than during 2012, said the 2013 Arctic Report Card.
Saving Greenland's Ice Sheet is Imperative
Human-caused global warming has set in motion an unstoppable slow-motion collapse of the glaciers in West Antarctica capable of raising global sea level by 4 feet (1.2 meters) in a few hundred years, said NASA in a May 2014 press release. What's more, one of the glaciers involved, the Thwaites Glacier, acts as a linchpin on the rest of the ice sheet, which contains enough ice to cause a total of 10 to 13 feet (3 to 4 meters) of global sea level rise over a period of centuries. This unstoppable collapse makes saving Greenland "absolutely essential", said glaciologist Richard Alley in a May 2014 interview in Mother Jones. Greenland's ice sheet holds enough water to raise global sea levels by 7.36 meters (24.15 feet) were it all to melt, and civilization would be hard-pressed to deal with 10 - 13 feet of sea level rise from West Antarctica, let alone another 20+ feet from Greenland. "If we've committed to 3.3 meters (10.8') from West Antarctica, we haven't committed to losing Greenland, we haven't committed to losing most of East Antarctica," said Alley. "Those are still out there for us. And if anything, this new news just makes our decisions more important, and more powerful." Unfortunately, the Greenland Ice Sheet is much more vulnerable to melting than previously thought, found a May 2014 study by Morlighem et al., Deeply incised submarine glacial valleys beneath the Greenland ice sheet. The researchers found that widespread ice-covered valleys extend much deeper below sea level and farther inland than previously thought, and would likely melt significantly from steadily warming waters lapping at Greenland's shores.
Support for the Dark Snow Hypothesis
Observational evidence for the Dark Snow project's hypothesis that upwind forest fires might darken the Greenland Ice Sheet and cause significant melting was provided by a May 2014 paper by Keegan et al., Climate change and forest fires synergistically drive widespread melt events of the Greenland Ice Sheet. Their ice core study found that black carbon from forest fires helped caused a rare, near-ice-sheet-wide surface melt event that melted 97% of Greenland's surface on July 11 - 12 2012, and a similar event in 1889. Since Arctic temperatures and the frequency of forest fires are both expected to rise with climate change, the results suggest that widespread melt events on the Greenland Ice Sheet may begin to occur almost annually by the end of century.
Another factor contributing to a darker Greenland Ice Sheet and more melting may be additional wind-blown dust landing on the ice, according to a June 2014 study, Contribution of light-absorbing impurities in snow to Greenland's darkening since 2009. In an interview with ClimateWire, lead author Marie Dumont of France's meteorological agency said, "Our hypothesis is that now that seasonal snow cover in the Arctic is retreating earlier than before, and bare soil is available earlier in the Spring for dust transport."
