Deforestation is no Longer Cool at Mount Kilimanjaro
Local deforestation is believed to be linked to changing weather patterns at Mount Kilimanjaro in Kenya. The study, which was carried out by the University of Alabama in Huntsville suggests that deforestation is causing snow caps and glaciers at the top of the mountain to melt and recede. The research was conducted by using data from NASA satellites and regional climate models.
The study was led by University of Alabama's Dr Udaysankar Nair who is a research scientist that works in the Earth System Science Center along with Jonathan Fairman, a NASA Earth System Science fellow with the university. Evidence taken from a 2000 square miles area at the top of the mountain that was taken in July suggests that cutting down trees in the region is having an impact on the mountain and its surrounding areas.
The research was carried out with the help of Dr. Thomas Mölg and the University of Innsbruck and the University of Alabama's Dr. Sundar Christopher. By using two NASA satellites equipped with moderate resolution imaging spectroradiometer instruments, the researchers could analyse the surface of forested and deforested land around the region of the mountain.
The ice caps on Mount Kilimanjaro are believed to have been roughly 150 square kilometres 16,000 years ago. However, today the ice caps are a tiny fraction of this and the trends suggest that due to manmade global warming the ice caps are decreasing at a rapid rate. In the 1880's, the ice caps were judged to have covered 20 square kilometres, but from 1912 they have decreased from 12 square kilometres to less than two square kilometres today.
The data was recorded by Dr. Nair and his team in July as it was believed that the month would not see any unusual weather activity. "We figured that the impact of local systems such as deforestation would be greater when large scale weather events aren't there. Kilimanjaro is an isolated mountain, so under normal circumstances most of the local air flow goes around the mountain. When you cut down forests you reduce surface roughness, which increases wind speed at higher elevations on the windward slopes. That faster wind over steep upper slopes causes more intense cloud formation and precipitation up the side of the mountain," said Dr Nair.
Nair and Fairman intend to extend their project in order to analyse the more extreme weather patterns that come in from the Indian Ocean during other seasons."We need to look at the complete annual cycle before we understand the impacts that deforestation is having on the mountain peak," said Fairman.
The project is an ongoing process, but Nair compared the research to some of the studies that have been carried out in Costa Rica. "When we look beyond the summer dry season, our results suggest that regional deforestation has the potential to either mitigate or enhance large scale climate change. In some places, like Costa Rica, deforestation clearly adds to the effects of climate change. For Kilimanjaro, we expect our extended model simulations to reveal whether deforestation will worsen or mitigate large scale changes."
Photo credit: Muhammad Mahdi Karim