From David Dare
Your article on tropical glaciers (30 January, p 10) took me back to my time surveying the snout of the San Pablin Glacier in Colombia in 1959. In recent years I have attempted to locate the glacier in photographs of the area and on Google Earth. The article explains why I have been unable to do so.
It should be noted that even 57 years ago there were some indications that the glacier was in retreat – the amount of pristine moraine and sand exposed below the glacier's snout – although climate change as we now understand it was unknown to us.
Edinburgh, UK
