Warming-induced glacier retreat could create novel ecosystems

Subject: Environment

Section: Climate change

Context:

Climate change caused by human activity under a high-emissions scenario may halve the area covered by glaciers outside the Antarctic and Greenland ice sheets by the end of the century, as per a study published in Nature.

Details:

Less than half of glacial areas are located in protected areas.
This will have marked ecological and societal cascading consequences, as novel ecosystems develop to fill emerging new habitats.
However, there has been no complete spatial analysis carried out to quantify or anticipate the important changeover.

What does the study say?

Under a high-emissions scenario (in which global greenhouse gas emissions triple by 2075), about half of 2020 glacier area could be lost by 2100.
However, this could be curbed by a low-emissions scenario (in which net zero is achieved by 2050), which would reduce this loss to approximately 22%.
As per the modeling exercise undertaken by Jean-Baptiste Bosson from the Conservatory of Natural Areas of Haute-Savoie, Annecy, France and others, the loss of glacier area will range from 22% to 51%, depending on the climate scenario.
It would mean that by 2100, the decline of all glaciers outside the Antarctic and Greenland ice sheets may produce “new terrestrial, marine and freshwater ecosystems over an area ranging from the size of Nepal (1,49,000 sq. km) to that of Finland (3,39,000 sq. km)”.

Probable features of novel ecosystem:

In the deglaciated areas, the new ecosystems will be characterised by:
- “Extreme to mild ecological conditions” encompassing terrestrial, freshwater and even marine habitats.
- Might favour primary productivity
- Increased numbers of non-native species that can thrive as cold-adapted species and generalist species.
- It will increase the complexity of glacial dynamics and will increase the challenge of glacier conservation.

Probable solution:

There is an urgent need to urgently and simultaneously enhance climate-change mitigation and the in-situ protection of these ecosystems to secure their existence, functioning and values.