Bad News: Greenland ice sheet melting at record rate
WASHINGTON (Reuters) – The Greenland ice sheet melted at a record rate this year, the largest ever since satellite measurements began in 1979, a top climate scientist reported on Monday.
“The amount of ice lost by Greenland over the last year is the equivalent of two times all the ice in the Alps, or a layer of water more than one-half mile deep covering Washington DC,” said Konrad Steffen of the University of Colorado at Boulder.
Using data from military and weather satellites to see where the ice is melting, Steffen and his colleagues were able to monitor the rapid thinning and acceleration of ice as it moved into the ocean at the edge of the big arctic island.
The extent of the melt area was 10 percent greater than the last record year, 2005, the scientists found.
There is published data, from respected sources, which contradict the widespread claims of ever accelerating melting of the Greenland Ice-sheet since 2002.
A) The greatest melting in recent times was in 2002, and that was on par with 1987.
B) It was warmer in Greenland during the early 1900’s than recently, and thus the extent of melting then, (before satellite detection), was probably greater than recently.
For instance, for B), the respected journal; Geophysical Research Letters, 13 June 2006, has published this paper by Chylek et al:
ABSTRACT:
We provide an analysis of Greenland temperature records to compare the current (1995-2005) warming period with the previous (1920-1930) Greenland warming. We find that the current Greenland warming is not unprecedented in recent Greenland history. Temperature increases in the two warming periods are of a similar magnitude, however, the rate of warming in 1920-1930 was about 50% higher than that in 1995 – 2005.
For more information: http://meteo.lcd.lu/globalwarming/Chylek/greenland_warming.html
Concerning A), I quote from your lead article:
[for 2007] “…The EXTENT of the melt area was 10 percent greater than the last record year, 2005, the scientists [Konrad Steffen] found…” [emphasis and context added]
However, this statement is contradicted by Steffen’s own publication of September 28, 2005, and by a NASA release of September 25 2007. (See links below). A visit to Steffen’s Home Page and Publication List reveals no later publication, or explanation for his recent verbals. If you consult his latest published data, you will see, that there is a graph indicating somewhat similar melt EXTENT in 1987, 1991, 1998, 2002, and 2005, but that 2005 is slightly lower than 2002. The text wanders around somewhat, and makes some questionable comparisons, so it is best to go straight to the graph and look at the data:
http://cires.colorado.edu/science/groups/steffen/greenland/melt2005/
The more recent graphical data from NASA GSFC, (Which also has a doubtful text preamble), shows that 2003, 2004, 2005, 2006, and 2007, ALL had a lower melt INDEX than 2002, and thus strongly contradicts Steffen’s talk. (Note: GSFC’s “INDEX” = extent x duration, and is more meaningful than Steffen’s EXTENT, which might only be for a few unusually-hot days)
http://www.nasa.gov/vision/earth/environment/greenland_recordhigh.html
There are a number of anomalies or irrelevances in both reports, but if we keep it simple, and look at the data in the graphs, Konrad Steffen and some other alarmists are strongly contradicted by the DATA.
Notice also, that none of these reports mention that current warming in Greenland is not unprecedented. (See also, Box et al 2002)