While there is considerable uncertainty about what effects such climatic changes may have on northern range vegetation, there is no longer any question that these changes are real and continue today. Note especially the extreme and historically unprecedented dryness of 1988, when Yellowstone experienced fires on a scale apparently not equalled since about 1700. Courtesy of G. Meyer, Middlebury College. While these declines may seem small and insignificant in the Yellowstone area, small numerical changes may have large effects. As noted earlier, the difference between 16 and 18 inches of precipitation may be the difference whether seedling junipers survive or not.
Winter range soil temperatures are generally cool.
It is a matter of some interest whether or not the changes in climate experienced by Yellowstone during the 1900s are in part the result of human influence on the atmosphere. These scenarios feature significant changes in vegetation communities, with consequences ranging from minor to grave for various mammal species. For example, a slight warming and drying of the park's climate will almost eliminate whitebark pine, an important food species for grizzly bears and other animals. Yet another reason to continue the present investigations of the northern range is the opportunity this research provides to establish baseline information against which to measure such changes. Over the past 20 years much of greater Yellowstone has been subjected to intense scrutiny using palynological methods to reconstruct paleoclimates.