Rising temperatures could shrink the area covered by alpine glaciers worldwide by more than a fifth this century, exposing vast swathes of land to the atmosphere for the first time in thousands of years. New research shows that emerging habitats created as ice retreats present challenges as well as opportunities for conservation efforts.
Alpine glaciers outside Antarctica and Greenland currently cover approximately 650,000 square kilometers. They provide summer water for nearly 2 billion people as well as ecosystems worldwide, and their retreat has provided striking evidence of the dangers of global warming.
The researchers modeled the future of these glaciers, as well as the terrain they would leave behind, under both low and high greenhouse gas emission scenarios. This exposure more than doubles in the high-emissions scenario, with the largest areal impacts seen in Alaska and the high mountains of Asia.
lead author Jean-Baptiste Bosson, a glaciologist at the Haute-Savoie Natural Areas Conservatory (ASTERS) says “This could be one of the biggest ecosystem changes on our planet”.
Bosson and his colleagues predict that approximately 78% of the newly exposed terrain would be on land, while 14% and 8% percent of the ice-free areas would occur in marine and freshwater regions, respectively.
Many of these areas could provide vital new habitat that must be protected: colonization by plants could lead to increased carbon storage at a time when forests are being destroyed elsewhere, while also providing new habitats for climate-threatened animals changes in lower positions.
The study provides a useful clue for scientists working to understand how microorganisms, plants and animals move into pristine spaces, says Francesco Ficetola, a zoologist at the University of Milan in Italy who studies glacial ecosystems. It could also help governments prepare for inevitable questions about land management: less than half of the glacial areas analyzed in the study are currently in parks and other protected areas.
In the future, there is a need to integrate such global analyzes with detailed ecological studies that will form the basis for monitoring the development of these new habitats, says Ficetola. “This will allow us to develop a more accurate prediction of what will happen in each deglaciated region of the planet.”
For Bosson, the study is another reminder of what’s at stake as the world works to reduce greenhouse gas emissions. “We’re at a tipping point for the glaciers,” he says. “We can save something like 75% of the current ice by the end of this century, but we have to act.”