New UGent research shows that more snowfall in the future could slow or offset the negative effects of climate change on glaciers in southern Patagonia.
Precipitation is more important than temperature
The scientists first examined how glaciers responded to climate changes in the past. Using a computer model, they simulated how changes in temperature and precipitation affected glaciers in Patagonia over the past six thousand years.
They found that precipitation in particular was responsible for fluctuations in glacier volume , while temperature had a smaller influence. Precipitation in the form of snow can build up glaciers, while warmer temperatures cause them to melt.
Simulation of the future
The research team then went a step further and simulated the future dynamics of glaciers under 21st-century climate change. These simulations showed that precipitation would have to increase by 10 to 50 percent in the future to maintain the amount of ice these glaciers currently hold , depending on the amount of greenhouse gases emitted into the atmosphere.
Specifically, if warming in southern Patagonia is limited to 1.5°C, an increase in snowfall could maintain glacier extent. However, if regional temperatures rise more than 1.5°C, an increase in precipitation may not be sufficient to prevent significant glacier retreat. With current emissions, Patagonia is headed for warming of more than 2.8°C in the 21st century.
"Our findings suggest that precipitation has the potential to reduce glacier mass loss, provided warming is controlled. However, if emissions are not greatly reduced, it is unlikely that snowfall can compensate for ice loss. This could push glaciers into a new regime dominated by rain instead of snowfall. Our study shows that this has not occurred in southern Patagonia in the past six thousand years," said Matthias Troch.
Results have implications for future of glaciers around the world
If greenhouse gas emissions are not reduced, many glaciers will disappear and sea levels will rise. However, this new research suggests that - if we can limit emissions - even a modest increase in precipitation could slow or even reverse the loss of glacier mass in marine areas.
Further research will have to show whether more snowfall in the future can also prevent mass loss of glaciers in other regions, such as Norway, Alaska, Iceland and New Zealand.
"The findings of our research underscore the importance of reducing greenhouse gas emissions to mitigate the effects of climate change on glaciers and sea levels," said Matthias Troch.
More information
- The authors of the study were funded by UGent, CU Boulder, the Belgian American Educational Foundation, the Norwegian Research Council, the French Ministry of Higher Education, Research and Innovation and the French research agency ANR.
