Himalayan glaciers are cooling despite climate change

It may seem paradoxical: temperatures around the world are rising, but the glaciers in the Himalayas are cooling. The reason for this is the special wind. A similar phenomenon is unlikely to occur in the Swiss Alps.

Despite rising temperatures, parts of Himalayan glaciers remain cold: according to a new study, global warming is triggering a cooling reaction there.

They allow cold winds – called katabatic winds – to slide down the slopes, and thus can sustain the surrounding ecosystems for the time being. This was demonstrated by an international research team in the journal Nature Geoscience.

According to the study, cold winds are caused by higher temperatures: in the Himalayas, this leads to a greater difference between the warmer ambient air and the air mass that is in direct contact with the icy surface of the glaciers.

Therefore, the turbulent heat exchange at the glacier surface increases and the surface air mass cools more strongly. These cold and dry air masses become denser and then flow down the slopes into the valleys due to gravity and exchange with the warmer air layers on the slopes.

Glaciers cannot be stopped from melting

Study leader Francesca Pellicciotti told the Austrian news agency APA that this will not affect the trend towards melting glaciers. “Although there will be areas that will get a little colder in the near future, the glacier will continue to melt steadily because katabatic winds have a dual effect,” Pelliciotti said.

The reason for this is that glaciers on the southern slopes of the Himalayas are called accreting glaciers – that is, they gain mass through rainfall during the summer monsoon at high altitudes and simultaneously lose it through continuous melting.

Masses of cold air flowing from glaciers reduce the amount and height of precipitation. This means that glaciers lack important mass flow.

There is no cooling with alpine glaciers

According to the glaciologist, the chances of delays due to similar phenomena for glaciers in the Alps are slim: “It is very unlikely, because strong katabatic winds require primarily large masses of ice. Those in the Alps are probably too small for that. ( cda/aba)