The IPCC and its supporters claim that one of the major effects of global emissions is to cause glaciers to retreat, with the clear implication that if we don’t drastically reduce our emissions of CO2,they will disappear.
No-one can forget the claim in the IPCC’s 2007 report that the galciers in the Himalayas would disappear by 2035.
The IPCC’s report in 2007 said “glaciers in the Himalayas are receding faster than in any other part of the world and, if the present rate continues, the likelihood of them disappearing by the year 2035 and perhaps sooner is very high if the Earth keeps warming at the current rate.” The claim appears in the full report, but not in the more widely read “Summary for policymakers”.
The claim was attributed to a report by the campaign group WWF, but in the New Scientist article, Guardian writer Fred Pearce noted that WWF had cited a 1999 interview in the magazine with Indian glaciologist Syed Hasnain as the source of the claim. Hasnain told the magazine last week that “it is not proper for IPCC to include references from popular magazines or newspapers”.
However there is clear scientific evidence that glaciers have at least as far back as the end of the last Ice Age regularly retreated, during warm periods, and advanced, during cool periods.
A new paper published in Quartenery Science Reviews (Munroe et al. 2012) finds that alpine glaciers in Glacier National Park, Montana retreated up to 6 times faster during the 1930′s and 1940′s than over the past 40 years.
The Multi-proxy study of sediment cores retrieved from lakes below modern glaciers supports the first detailed Neoglacial chronology for Glacier National Park (GNP) and shows maximum reconstructed retreat rates [in] 1930″ of about 125 meters per year, compared to near zero in ~1975 and about 20 meters/year at the end of the record in 2005. The authors report, “Results indicate that alpine glaciers in Glacier National Park advanced and retreated numerous times during the Holocene after the onset of Neoglaciation 6,500 years before the present” and “Retreat from the Little Ice Age maximum was the most dramatic episode of ice retreat in at least the last 1000 years.”
15 October 2012 Jeffrey S. Munroe | Thomas A. Crocker | Alena M. Giesche | Lukas E. Rahlson | Logan T. Duran | Matthew F. Bigl | Benjamin J.C. Laabs
Multi-proxy study of sediment cores retrieved from lakes below modern glaciers supports the first detailed Neoglacial chronology for Glacier National Park (GNP), Montana. Analysis focused on sedimentary properties sensitive to the extent and activity of upstream glacier ice, including: water, organic matter, carbonate, and biogenic silica content; bulk density; mass accumulation rate; phosphorus fractionation; magnetic susceptibility; L*a*b* color values; and grain size distribution. Results indicate that alpine glaciers in GNP advanced and retreated numerous times during the Holocene after the onset of Neoglaciation ca 6500 BP.
The two oldest phases of glacier expansion were synchronous with the well-documented Garibaldi (5600–6900 BP) and Tiedemann-Peyto (1900–3700 BP) phases in western Canada. Younger phases correspond with the First Millennium Advance in western Canada, as well as glacier with advances in the Sierra Nevada. The culminating Little Ice Age (LIA) advance was the most recent and extensive of a series of advance/retreat cycles over the past millennium. Retreat from the LIA maximum was the most dramatic episode of ice retreat in at least the last 1000 years.
Like everything else cited by the IPCC as caused by human emissions of CO<sup>2</sup> the advance and retreat of glaciers is a cyclical phenomenon, with natural causes.