Scientific research now paints a clearer picture of the implications of melting glaciers on humans, diverse species, and the ecosystems they inhabit. A startling revelation from a study published in Nature highlights that, if the current high-emission scenario continues, about half of the area covered by glaciers, excluding the Antarctic and Greenland ice sheets, may vanish by 2100. This means losing a landmass approximately equivalent to Nepal and Finland combined.
- Under high emissions, glaciers’ retreats will happen swiftly, resulting in a swift ecological transition.
- The retreating glaciers can lead to the emergence of “novel” ecosystems. These can attract cold-adapted species from regions farther south that become inhospitable due to increasing warmth.
- Simultaneously, the retreat can jeopardize species dependent on icy environments, with some even facing the threat of extinction.
- Post-glacial ecosystems will vary in ecological conditions, ranging from extreme to mild. These could either provide a refuge for cold-adapted species or promote the growth of primary productivity and generalist species.
Species at Risk
Species dwelling near glaciers face an existential crisis. “In places like the Alps or the Himalayas, species that are adapted to cold climates are limited in movement and cannot easily adapt to the fast-warming environment,” explains Nicolas Lecomte, a professor at the University of Moncton.
Though some cold-adapted species displaced by the rising temperatures will find refuge in these emerging ecosystems, only a “very narrow range” with the capacity for mobility, such as certain mammals and birds, can effectively relocate. And this refuge may be temporary, as these habitats too will change at a rapid pace.
Humans are not insulated from the repercussions of these ecological shifts. For many densely populated regions, glaciers are a primary water source as they feed some of the world’s largest rivers. Their retreat could destabilize these essential water sources and result in catastrophic flooding events, such as the recent glacial flood lake outburst in Alaska.
To forecast the response of each individual glacier to diverse climate scenarios up to 2100, the research utilized a glacier evolution model. This model integrates glacier outlines, digital elevation models of subglacial terrain, and climatic data. Predictions from the model suggest that deglaciation will proceed at a comparable pace until 2040, irrespective of the climate situation. However, post-2040, glacier retreat projections will differ based on emission levels.
- If emissions triple by 2075, approximately half of the glacier-covered area in 2020 could vanish by 2100.
- A drastic emission reduction, achieving net zero by 2050, could limit the loss to 22%.
The Urgency of Action
Merely curbing deglaciation isn’t enough. The emphasis should also be on conserving the newly developing ecosystems. Regrettably, currently, less than half of glacial regions are within protected zones. This underscores the immediate need for climate change mitigation and ecosystem preservation efforts.
The United Nations’ declaration of 2025 as the International Year of Glaciers’ Preservation, coupled with the Global Biodiversity Framework’s emphasis on enhanced climate change mitigation, underscores the global recognition of this impending crisis.
Glacier shrinkage induced by human-driven climate change threatens not just biodiversity and freshwater resources but also us. As these glaciers give way to new ecosystems, the onus is on humanity to swiftly adapt and take urgent measures to mitigate the impacts and safeguard these delicate and vital ecosystems.