I reckon it is nearly impossible to keep up with the climate change literature particularly the latest climate change scare story. Working out whether a particular piece of information is invented, real, real but exaggerated, etcetera, certainly takes effort.
Brisbane’s newspaper, The Courier-Mail, has a story on page 19 of this weekend’s edition titled ‘Greenland ice sheets double melt rate’.
“Global warming is melting Greenland’s glaciers much faster than previously believed, raising fears that sea levels will rise rapidly during the next century”
This is how it works according to a latest issue of Science magazine:
“The Greenland Ice Sheet gains mass through snowfall and loses it by surface melting and runoff to the sea, together with the production of icebergs and melting at the base of its floating ice tongues. The difference between these gains and losses is the mass balance; a negative balance contributes to global sea-level rise and vice versa. About half of the discharge from the ice sheet is through 12 fast-flowing outlet glaciers, most no more than 10 to 20 km across at their seaward margin, and each fed from a large interior basin of about 50,000 to 100,000 km2. As a result, the mass balance of the ice sheet depends quite sensitively on the behavior of these outlet glaciers.
Two changes to these glaciers have been observed recently. First, the floating tongues or ice shelves of several outlet glaciers, each several hundred meters thick and extending up to tens of kilometers beyond the grounded glaciers, have broken up in the past few years. Second, measurements of ice velocity made with satellite radar interferometric methods have demonstrated that flow rates of these glaciers have approximately doubled over the past 5 years or so.”
This article in Science (Vol. 31, pg 963-964) goes on to explain that 2002 and 2005 are records for “melt extent over the 27 years of observation” – which I assume refers to the last 27 years.
Contrast this information with an article titled “Recent cooling in coastal southern greenland and relation with the north atlantic oscillation” published in 2003 by Edward Hanna and John Cappelen (Geophysical research letters, VoL. 30, NO. 3, 1132).
This research paper which covers the period up until 2002 (the year there was record melting according to the new article in Science magazine)states:
“Analysis of new data for eight stations in coastal southern Greenland, 1958-2001, shows a significant cooling (trend-line change -1.29C for the 44 years), as do sea-surface temperatures in the adjacent part of the Labrador Sea, in contrast to global warming (+0.53C over the same period). The land and sea temperature series follow similar patterns and are strongly correlated but with no obvious lead/lag either way. This cooling is significantly inversely correlated with an increased phase of the North Atlantic Oscillation (NAO) over the past few decades (r = -0.76), and will probably have significantly affected the mass balance of the Greenland Ice Sheet.
This 2003 paper only refers to coastal southern Greenland, while the new Science paper refers to “several large glaciers” and the last 5 years or so.
Thanks to Phil Done for alerting me to the new paper in Science and Benny Peiser for the link to 2003 paper.