Earth's retreating glaciers are creating huge alien ecosystems

A distinctive outcome of this shift is the emergence of novel ecosystems that swiftly colonize newly unveiled terrains. However, the global scope of this phenomenon has remained largely unexplored—until now.

Led by Jean-Baptiste Bosson from the Conservatory of Natural Areas of Haute-Savoie, France, a research team conducted an extensive analysis. 

They harnessed a comprehensive global glacier evolution model to map out the anticipated course of more than 650,000-kilometer square (km²) of glaciers situated beyond the Antarctic and Greenland ice sheets.

They used a model that incorporated the outlines of glaciers, information about the terrain beneath the glaciers, and different climate factors to predict how each glacier would react to various climate scenarios up to the year 2100.

Notably, the model extends its predictions to the nature of ecosystems that will materialize in the wake of deglaciation, categorized as marine, freshwater, or terrestrial.

Emission intensity

The study's findings underscore a critical pattern: irrespective of the climate scenario, deglaciation maintains a consistent pace until 2040. After that, outcomes diverge based on emission intensity. 

Under a high-emissions trajectory, which envisions a tripling of global greenhouse gas emissions by 2075, nearly half of the 2020 glacier area could vanish by 2100. 

Yet, an alternative low-emissions pathway, targeting net-zero emissions by 2050, may mitigate the loss to around 22 percent.  

Projected deglaciation could expose land equivalent to the combined area of Nepal and Finland by the century's end—comprising terrestrial, marine, and freshwater habitats. 

This evolving landscape may harbor species seeking refuge from the escalating effects of climate change elsewhere.

The implications of the research extend beyond quantifying the extent of glacier decline. The study urges a dual approach: not only curbing deglaciation rates but also safeguarding these developing ecosystems to ensure their enduring survival. 

As the world grapples with the urgency of climate action, preserving these newly emerging ecosystems becomes a pivotal element in securing Earth's ecological equilibrium.

The complete study was published in Nature on August 16 and can be found here.

Study abstract:

Glacier shrinkage and the development of post-glacial ecosystems related to anthropogenic climate change are some of the fastest ongoing ecosystem shifts, with marked ecological and societal cascading consequences1–6 . Yet, no complete spatial analysis exists, to our knowledge, to quantify or anticipate this important changeover7,8 . Here we show 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 (149,000 ± 55,000 km2 ) to that of Finland (339,000 ± 99,000 km2 ). Our analysis shows that the loss of glacier area will range from 22 ± 8% to 51 ± 15%, depending on the climate scenario. In deglaciated areas, the emerging ecosystems will be characterized by extreme to mild ecological conditions, ofering refuge for cold-adapted species or favouring primary productivity and generalist species. Exploring the future of glacierized areas highlights the importance of glaciers and emerging post-glacial ecosystems in the face of climate change, biodiversity loss and freshwater scarcity. We fnd that less than half of glacial areas are located in protected areas. Echoing the recent United Nations resolution declaring 2025 as the International Year of Glaciers' Preservation9 and the Global Biodiversity Framework10, we emphasize the need to urgently and simultaneously enhance climate-change mitigation and the in situ protection of these ecosystems to secure their existence, functioning and values.