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Four Centuries of Climate Change in Nepal
Cook, E.R., Krusic, P.J. and Jones, P.D.  2003.  Dendroclimatic signals in long tree-ring chronologies from the Himalayas of Nepal.  International Journal of Climatology 23: 707-732.

What was done
The authors developed a 400-year temperature history of the Himalayan region of Nepal, which they describe as "the best yet produced from the 'High Asia' region spanning the Himalayas, Karakoram, and Tibetan Plateau," using 32 tree-ring chronologies based on five indigenous tree species and a monthly temperature record from the Indian Embassy in Kathmandu that stretches from 1879 to 1977, which they updated to 1992 with records from nearby meteorological stations located at comparable elevations.

What was learned
Cook et al. report that their temperature reconstructions (Feb-Jun and Oct-Feb} "reflect patterns of temperature variability associated with Little Ice Age cooling and warming into the 20th century," which is only to be expected.  But what about the "unprecedented" warming of the past quarter-century, which climate alarmists claim is cooking the world?

The US and British scientists report that "only the October-February reconstruction shows any indication of unusual late-20th century warming," but they fail to note that the temperatures of which they speak were not as great as those experienced a century earlier.  Hence, for the Oct-Feb season, there was no net warming, and maybe even a slight cooling, over the last hundred years of data availability.  As for the other part of the year (Feb-Jun), there actually was a net cooling, with temperatures dropping dramatically through the late 1950s and early 60s and remaining below the long-term average to the end of the record.

What it means
The temperature history of Himalayan Nepal developed by Cook et al. joins a number of other temperature records we have highlighted recently [see our Editorials of 10 Mar 2004 and 17 Mar 2004] that present no evidence whatsoever for extraordinary, or even modest, warming over the last quarter-century.  Clearly, the world is not rushing headlong toward a climate-catastrophe precipice or even meandering in that direction, as ever more high-quality studies are beginning to demonstrate.

Reviewed 28 April 2004