Abstract

Around the globe, mighty glaciers are retreating. In the European Alps and many other mid- and high-latitude locations, evidence clearly implicates global climate change—heat fluxes from warm air feeding processes that turn mighty glaciers into rivers of meltwater. High-altitude glaciers in the tropics are melting too; the area of the ice cap atop Kilimanjaro in tropical East Africa has shrunk more than 90 percent in a century and become a global-warming poster child. But Mote and Kaser say that the Kilimanjaro glaciers are not melting but sublimating—turning straight to vapor—under the direct action of solar radiation at temperatures that remain below freezing. Whatever is happening elsewhere, Kilimanjaro's ice seems not to be succumbing to climate change.