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Himalayan Glaciers
Chaujar, R.K. 2009. Climate change and its impact on the Himalayan glaciers - a case study on the Chorabari glacier, Garhwal Himalaya, India. Current Science 96: 703-708.

What was done
"Based on the dating of lichens, developed on loops of moraines formed due to various stages of advance and retreat of the [Chorabari] glacier," the author pinpoints the time at which the warming that led to the demise of the Little Ice Age -- and, ultimately, the ushering in of the Current Warm Period -- began in the Kedarnath temple area of the Garhwal Himalayas, after which he briefly reviews the similar findings of others at a variety of places around the globe.

What was learned
Chaujar reports that "research on various glaciers of the northern and southern hemisphere has shown that most of them started their retreat in the mid-eighteenth century, thereby indicating the end of the Little Ice Age maximum," which temporal coincidence, in his words, "suggests the possibility of a common trend in mountain areas of both hemispheres and the Himalayas," indicative of a global phenomenon.

What it means
The Indian researcher concludes that "these results suggest that climatic changes in the world started during early to mid-eighteenth century," which is long before the historical increase in the air's CO2 content could have been involved in the process of their retreat. Hence, we conclude there is no compelling reason to believe that late-20th-century global warming was anything more than a continuation of the non-anthropogenic-induced return of the earth from the frigid depths of the Little Ice Age, which was the coldest interval of the interglacial period in which we currently live. Humanity had nothing to do with the globe's descent into that record-breaking cold; and we have likely had little to do with the planet's recovery from it, which is now probably complete, as the earth has experienced no net warming over the past decade or so ... which is yet another reason to believe that we were not responsible for late-20th-century global warming.

Reviewed 10 June 2009