In the world of glaciology, the year 2007 would go down in history. It was the year a seemingly small error in a major international report heralded huge changes in our understanding of what was happening to the Himalayan glaciers.
Just one year after Al Gore’s documentary An Inconvenient Truth sparked conversations about anthropogenic (human-made) global warming, the Intergovernmental Panel on Climate Change (IPCC) published its 4th Assessment Report. This state-of-the-science summary was the gold standard to inform the world about climate change. The report contained one small but serious error – that all glaciers in the Himalayas would vanish by the year 2035.
The scandal sparked a flurry of new research, including my own, and we can now see that some Himalayan glaciers will survive into the next century. The latest data tells us that if we reduce our greenhouse gas emissions, then between one-third and one-half of glacier ice will be lost by 2100. If not, and we carry on with business as usual, then two-thirds of Himalayan glaciers will vanish by the end of this century.