Cryospheric Changes and Their Effects on Ecosystems in the Himalayas: Ecological Impacts Including Effects on Biodiversity and Entire Ecosystem

The Himalayas, also commonly known by the name "Third Pole," are a vitally significant component of the Earth's cryosphere. This great mountain range is a huge reservoir of enormous quantities of freshwater, which are stored in various forms like glaciers, extensive covers of snow, and permafrost layers.

Illustration by The Geostrata

The Himalayas are significant not just for their physical existence but also for serving a crucial role in regulating numerous hydrological processes, in addition to being significant in maintaining biodiversity and other fundamental ecological processes that sustain life. 

Climate change has triggered in the cryosphere a sequence of large-scale alterations. This has resulted in alarming alterations like the retreat of glaciers, the loss of snow cover, and the degradation of permafrost layers. Today, glaciers cover around 10% of earth’s total land area, during the last ice age they covered 32% of the earth’s land mass.

These extreme alterations have serious implications for not just the ecosystems that prevail in this region but also for the rich biodiversity that exists within it. In addition to the livelihood of the local inhabitants, who depend on these natural resources in order to survive. 

CRYOSPHERIC CHANGES IN THE HIMALAYAS

The Himalayan glaciers are receding at alarming rates with increasing temperatures. Separately from 1997 to 2012, snow cover reduced by 5.7% and the extent of permafrost decreased by about 100,000 km² between the 1970s and the 1990s. The Gangotri glacier is one of the fastest retreating glaciers and indicates the trends. Atmospheric pollutants such as black carbon cause the melting by reducing the albedo at the surface and increasing the absorption of solar radiation. 

PERMAFROST DEGRADATION

Since the past decades, the Himalayan permafrost has increased in temperature by 0.2 – 0.5°C and has triggered generalized degradation of such material substrate. Such developments have widespread hydrologic implications as well as a greater likelihood of natural hazards in the form of landslides and glacial lake outburst floods (GLOFs). 

FORMATION OF GLACIAL LAKES AND GLOFs

Glacier melting forms glacial lakes, which have the potential to produce devastating outburst floods. Floods pose a threat to downstream ecosystems via river morphological change and hydrological regime disruption. Cryospheric change results in the destruction of habitats for organisms of cold environments. Glacier recession and reduced snow cover signify the loss of alpine habitats, thus requiring species to shift towards higher altitudes or become extinct. The snow leopard and other organisms in the area are also threatened by habitat fragmentation. 

ENHANCED ACCESSIBILITY TO MODIFIED WATER 

Glacier meltwater is considered a precious resource, acting as a vital commodity for the downstream ecosystems. The presence of meltwater has a significant impact on the health and operation of aquatic ecosystems, while at the same time modifying the stream nutrient cycling processes in streams that encompass large rivers like the Indus, Ganges, and Brahmaputra.

Reduction in water flow can have negative impacts on fish populations as well as the riparian vegetation communities that rely on a sufficient water supply for growth and survival. Global warming alters phenological cycles in plants and animals. Flowering, pollination, and herbivore food availability are all affected by snowmelt dates. These alterations ripple through the food web and affect systems as a whole. 

EFFECTS ON COMPREHENSIVE AND INTERCONNECTED ECOSYSTEMS

Cryospheric changes exert a wide-ranging and profound effect on the hydrological processes taking place in the large and complex environment of the Himalayas. Glacial mass loss is an important cause of changes in the regimes of river flows in the region, resulting in large seasonal shortages in the supply of water resources.

This change in water supply exerts a strong influence on various sectors, such as agriculture, hydropower production, and the general accessibility of drinking water for local communities. Further, these disruptions extend their reach to the diverse wetland communities relying on a consistent and stable supply of water for their existence and well-being. 

INCREASED CRYOSPHERIC RISKS

The process of global warming greatly amplifies most threats, such as, but not restricted to, avalanches and landslides. In particular, the frequency of wet snow avalanches has risen as a direct result of warmer springs and changed winter conditions. Such threats carry grave hazards not just to populations of humans and to society in general but also have the capability to destabilize the earth's landscapes by instigating changes and alterations of landforms over a period of time. 

Permafrost thawing results in the release of the carbon stored in it into the atmosphere, which further contributes to the ongoing process of global warming.

Sediments formed due to black carbon air pollution also increase the rate of atmospheric ablation and play a major role in destabilising the various cryospheric systems. Glacier-meltwater-dependent mountain farming societies are severely affected by reduced water resources. Perennial river flow-dependent hydropower systems are also at risk. Growing cryospheric hazards demand additional disaster risk reduction. Policies must address avalanche and GLOF hazards as well as promote sustainable development practices. 

CONSERVATION PRACTICES

Black carbon and other pollutant emissions reduction can slow down glacier melting. Clean energy sources have to be transitioned to in order to reduce the impact. Conservation has to include the preservation of cold-adapted species through the restoration of habitats and migration corridors.

Ecological shock resilience can be increased through community-based approaches. More advanced monitoring systems must be put in place in order to gain a better understanding of the cryosphere dynamics. Ground observations and satellite observations can yield important information in terms of the rate of glacier loss, snow cover and permafrost status.

The changes occurring in the Himalayan cryosphere pose a serious and alarming threat to many ecosystems, the rich diversity of biodiversity within them, and the very survival of millions of human societies relying on them.

To effectively reduce the impacts resulting from these changes, it is necessary to take integrated approaches involving both scientific studies and sustainable development strategies. By taking steps to minimise ecological disturbances—such as actively reducing atmospheric pollution, enhancing observing capacity, and preserving the fine web of biodiversity—ecological resilience can be significantly increased at the same time as minimising any potential disturbances in this extremely sensitive area.

It is essential to realise that cryospheric changes are a serious global concern, affecting not just a specific region but with far-reaching implications for climatic systems worldwide and for global water security. It is thus clear that global cooperation among all countries relying on and utilising the precious resources of the Himalayas is an absolute necessity to achieve ecological stability and ensure long-term sustainability.

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BY ARYAVEER SHARMA

CENTRE FOR ENVIRONMENT AND CLIMATE ACTION

TEAM GEOSTRATA

info@thegeostrata.com