~70 years of glacier monitoring in Mexico

Glaciers in México have been present for the last decades on the highest mountains of México: Iztaccíhuatl,Popocatépetl and Citlaltépetl.

In 1964 the size of twelve glaciers was measured at Iztaccíhuatl volcano using aerial photographs resulting in an extension of 1.4 km². At the time of this review, El Pecho is the only remaining glacier on this mountain which exceeds the projections proposed earlier. Although much of the glacial retreat is related to climate change, in situ observationssuggest that geothermal heat fluxes and hydrothermal flows in the crater area should also be considered.

About the glaciers of Popocatépetl the glacial area in 1964 was 0.72 km² and consisted of three glaciers. Before 1994, the retreat of glaciers was in the order of ~10,000 m²/year. On December 21, 1994, an eruptive period began atPopocatépetl volcano characterized by volcanic explosions alternating with lava dome construction-destruction phases.An increase in heat flow under the glacial ice, the fall of tephra on its surface, and pyroclastic flows that moved over the glacier surface, caused its irregular thinning, retreat and, in the final stage, its fragmentation between1994-2001.

At Citlaltépetl volcano the existence of 9 glaciers was established, covering an area of 2.04 km². In 2007 they covered an area of 0.62 km², and by 2019 the bedrock was exposed, faster than anticipated previously. The accumulation zone of the glacier system is not existent ever since. Exposure of the bedrock increases solar energy transference as heat to the adjacent ice and snow, causing an increasing melting. At the same time, it prevents the flow of ice towards the ablation zone, causing an accelerated retreat of the glacier front. So, the surface of the glacier in 2019 was ~0.46 km², and the current extension for 2024 is only ~0.37 km².