Temps de lecture :2 minutes
Kilimanjaro’s snow is a symbol of climate change. It is also the issue of a stormy debate. Indeed, the snow that Ernest Hemingway believed to be eternal is disappearing: It has lost 80% of its surface area over a century. However, this complex phenomenon is in fact a bad example to illustrate climate change.
Indeed, the culprit is not the one we suspect : it is not the increase in global temperature which seems to cause the phenomenon. Firstly, because the glacier is at a high altitude, the temperature very rarely goes above zero, and even -3°C. It is also because the glacier started melting much before the 1950s when the increase in temperature became noticeable.
The determining factor rather seems to be the decrease in precipitation. Indeed, the evolution of glaciers depends on the the accumulation of ice through precipitation in the form of snow and its disappearance, through melting or sublimation. However, since the end of the 19th century, East Africa’s climate has changed. The air is becoming dry because there are fewer humid winds coming from the Indian Ocean. This could explain why the ice is disappearing.
This does not mean that man is innocent. Global warming increases this local change in winds and deforestation in the region is making the drying worse. Indeed, forests add humidity to the air and those below the glacier have mostly been destroyed to free up agricultural space. Since 1976, dew has therefore decreased by about 25%.
This counterexample should not overshadow the reality of climate change. Even though the ice in Kilimanjaro is not melting because of global warming, almost all the planet’s glaciers are melting for this same reason. Over the last decade, they have lost a total of 300 billion tons a year.