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New Scientist
25 September 2010 AGGRESSIVE tree-felling on mount Kilimanjaro could be partly to blame for its vanishing ice cap. The ice on Kilimanjaro’s summit has shrunk to just 15 per cent of its extent in 1912, leading campaigners to hold it up as a symbol of climate change. But other factors are also at play. For instance, the air at the summit is getting drier, reducing the snowfall that replenishes the ice and reflects solar radiation. Now Nicholas Pepin from the University of Portsmouth, UK, and colleagues say deforestation could be an important part of the puzzle. Between September 2004 and July 2008, the team took hourly humidity and temperature readings at 10 elevations on the mountain. These revealed that daytime heating generates a flow of warm, moist air up the mountainside (Global and Planetary Change, DOI: 10.1016/j.gloplacha.2010.08.001). Trees play an important role here by providing moisture through transpiration. Pepin suggests that extensive local deforestation in recent decades has likely reduced this flow of moisture, depleting the mountain’s icy hood.

Kilimanjaro’s vanishing ice due to tree-felling