Paper Reviewed
Kullman, L. 2014. Recent cooling and dynamic responses of alpine summit floras in the southern Swedish Scandes. Nordic Journal of Botany 32: 369-376.

According to Kullman (2014), "many studies display upshifts of trees, shrubs and ground-cover species in supposed response to a widespread episode of rising temperatures since the late 20th century and culminating around the millennium shift," citing fourteen different publications; and he goes on to state that "a coupling of alpine floristic dynamics to climate variability would be more convincing, and the results more useful for dynamic modeling, if it were demonstrated that alpine plant species richness declined in response to decadal trends of climate cooling," while noting that as far as he knows, "no such study exists."

In an effort to fill this void, Kullman analyzed plant species richness on several alpine summits in the southern Swedish Scandes between 2004/2006 and 2012, which period, in his words, "experienced consistent summer and winter cooling and finalized with a cold and snow rich summer 2012."

The Swedish scientist discovered that (1) "plant species richness on high alpine summits decreased by 25-46% between 2004/2006 and 2012," that (2) "most of the lost species have their main distribution in subalpine forest and the low-alpine region," but that (3) they "advanced upslope and colonized the summit areas in response to warmer climate between the 1950s and early 2000s," that (4) "despite the reduction in species numbers, the summit floras are still richer than in the 1950s," and that (5) "substantial and consistent climate cooling (summer and winter) during a decade preceded the recent floristic demise."

"Taken together," Kullman states that his results "highlight a large capability of certain alpine plant species to track their ecological niches as climate fluctuates on annual to decadal scales."