Observed reductions in mountain ice in the Andes, Alps and Africa were attributed to global warming in the most recent report by the Intergovenmental Panel on Climate Change, but the data sourced was questionable. One of the sources was an article in a climbing magazine based on anecdotes. Another was a dissertation from a Swiss masters program student who interviewed mountain guides from the Alps. Karl at Hot Air adds:

Neither the article nor the dissertation was subject to peer review. Moreover, the Sunday Telegraph notes that the latest IPCC report made use of 16 non-peer reviewed reports from the World Wildlife Fund.