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Does Global Warming Decline with Increasing Elevation?
Seidel, T.M., Weihrauch, D.M., Kimball, K.D., Pszenny, A.A.P., Soboleski, R., Crete, E. and Murray, G. 2009. Evidence of climate change declines with elevation based on temperature and snow records from 1930s to 2006 on Mount Washington, New Hampshire, U.S.A. Arctic, Antarctic, and Alpine Research 41: 362-372.

The authors write that "future predictions of climatic change and impacts on mountain ecosystems are frequently based on the most proximate low elevation data or on extrapolations from other mountain regions." However, they say that "using surrogate climatic data to describe potential responses by mountain biota can result in compromised conclusions." As one example, they note what they call "the assumption that alpine ecosystems may be at great risk," as most climate alarmists vociferously contend they are, because of what they typically describe as unprecedented global warming.

What was done
Working at Mount Washington (4416'N, 7118'W, the highest point in the northeastern United States), Seidel et al. compared seasonal and annual temperature trends, growing and thawing degree-day trends, and trends in two indices of snow season length for the summit (1914 m a.s.l.) and for Pinkham Notch (a mid-elevation site on the mountain's eastern side).

What was learned
Based on data for the period 1935-2003, the seven scientists determined that at the mid-elevation site "there is a statistically significant warming in both annual and summer temperatures, with greater warming than that observed on the summit and less than that reported for lower elevations in the region." In addition, they say summit temperatures, "though trending towards warming, do not exhibit a statistically significant change." What is more, they say there is evidence that "resistance to climate warming at the higher elevations on Mount Washington has considerable tenure," citing the work of Spear (1989), who, "using pollen and plant macrofossil records from Mount Washington and surroundings, concluded that since 5000 years BP, the subalpine forest and treeline-alpine ecotone boundary on Mount Washington has not exhibited demonstrable shifts."

One explanation for this mountaintop "climate stasis" may be related to the fact that Grant et al. (2005), as Seidel et al. describe it, estimated that "the summit of Mount Washington experiences free-atmosphere (troposphere) conditions on 50% of days in both summer and winter," so that "the summit exhibits a weak but not statistically significant warming trend, because during these conditions the summit would not necessarily be coupled with events observed from the surrounding regional lower elevation trends."

What it means
In the final paragraph of their paper, Seidel et al. say their results "support the conclusion that some mountains may only weakly follow regional low elevation surface climatic trends and may exhibit resistance to climatic warming with elevation." And these observations call into serious question the claim of NASA's James Hansen (and other climate alarmists) that life in alpine regions is in danger of being "pushed off the planet" in response to further global warming, as Hansen contended in his testimony to the Select Committee of Energy Independence and Global Warming of the United States House of Representatives on 6 June 2007.

Grant, A.N., Pszenny, A.A.P. and Fischer, E.V. 2005. The 1935-2003 air temperature record from the summit of Mount Washington, New Hampshire. Journal of Climate 18: 4445-4453.

Spear, R.W. 1989. Late-Quaternary history of high-elevation vegetation in the White Mountains of New Hampshire. Ecological Monographs 59: 125-151.

Reviewed 11 November 2009