WORLD WATER DAY 2025: PRESERVE THE GLACIERS

Ranjan Kumar Padmapati

(The writer can be reached at rkpadmapati@yahoo.co.in) 

Every year World Water Day is observed on 22nd March worldwide under the aegis of the UNO to highlight different crises facing the world community on matters relating to water. This year’s theme is “Preserve the Glaciers of the World”. When snow accumulation is more than it melts, glaciers are formed, serving as the largest reservoir of fresh water on earth and second only to the ocean as a reservoir of total water. A glacier is considered ‘in balance’ when the amount of snow that falls and accumulates at its surface is equal to the amount of ice lost through melting, evaporation, calving and other processes. A glacier is a river of ice often covered with ice and snow slowly moving down a valley from a mountain range with melt waters. Some glaciers are moving at a slow pace, a few centimetres per year, while others move several metres per day. Formation of glaciers took millennia; its size varies depending on the amount of ice it retains through its life span. The oldest glacier is Antarctica, 1,000,000 years old, and the other Greenland is 100,000 years old. Glaciers that exist today are mostly remnants of the last ice age. Glaciers are very critical for sustaining life and ecology and maintaining the water cycle. The rapid retreat of the glaciers in modern times threatens water availability, increasing the risk of food and energy security and natural disasters like floods, landslides and droughts, etc., hence necessitating transboundary cooperation.

The seriousness of the problem could be understood in that during 2023 glaciers lost 600 gigatons of water, the largest mass loss in the last 50 years. About 70% of Earth’s fresh water is stored in ice or snow. There are 275,000 glaciers worldwide, covering approximately 700,000 square km. Glaciers act as a protective cover for the earth, reflecting heat back into space and keeping the planet cool, known as the albedo effect. There are three places in the world where most of the ice is concentrated; the largest is Antarctica, followed by Greenland and the (HKG) Himalayan Glaciers, which are home to thousands of glaciers known as the third pole. Glacier melt depends on the rise in earth’s average temperature. The other climatic factors are rainfall, snowfall, etc., and the non-climatic factors are locations, altitudes, topography, slope, glacier beds and deposits of black carbon, pollutants, etc. Switzerland saw a glacier loss of 10% of the total mass between 2022 and 2023. It is a matter of much concern that 1/3 of the present heritage sites will disappear by 2050.

Glaciers support more than 2 billion people to replenish their rivers, lakes and groundwater to support ecosystems, agriculture, energy generation, industry and, more importantly, drinking water. Earth’s glaciers have been unnoticeably retreating since 1850 but more remarkably in modern times due to climate change. Melting of glaciers is an inexorable forward march; consequently, 9.6 billion tonnes of glaciers have melted since 1961. When temperature is in a rising trend, glaciers melt at faster rates than glaciers can form, leading to retreats.

The environmental scientists are of the opinion that by limiting the average temperature to 1.5 degrees Celsius, the earth can still save 2/3 of the world heritage glacier sites. The world heritage glaciers are losing, on average, 58 billion tonnes of ice per year. According to the United Nations University, between 2000 and 2019, glacier loss was 267 gigatonnes per year. Severe meltdown produces a maximum volume of water runoff known as ‘peak water’, after which water flow decreases abruptly because of shrinkages of glaciers. It is estimated that 2 billion people risk negative effects regarding water scarcity and livelihood loss due to glacier meltdown. The Hindu Kush Himalayan Mountain glacier extends 2,175 miles (ca. 3,500 km) from Afghanistan to Myanmar and is of much interest to India. It contains the largest volume of ice on earth outside two polar regions, is a source of waters for 12 rivers, including the Brahmaputra, Ganges, Indus, etc., that flow through 16 Asian countries, feeds 240 million people directly and supports about 1.65 billion people further downstream, better known as the Third Pole. It is a point of much concern that the HKH would shed 80% of its ice by the end of the century. It is estimated that if the temperature rise is within the following limits, the HKH will lose ice as follows – between 1.5 and 2 degrees Celsius, it is 30-50%; 3 degrees Celsius, 75%; and 4 degrees Celsius, 80% of its ice by 2100.

Simulations projected that a 4 degrees Celsius rise in temperature would eliminate nearly all the world’s glaciers. Melting of Greenland glaciers could be triggered at a temperature even at a lower temperature rise of 2-3 degrees Celsius because of lower elevation.

When glaciers retreat, lakes are formed behind the newly exposed terminal moraine. Rapid accumulations and expansions of waters in these lakes are evident and can lead to sudden breaching of the unstable natural dams behind which they are formed, and the resultant sudden discharge of huge amounts of water with debris, known as ”Glacier Lake Outburst Floods, often leads to catastrophic effects. There are at least 21 such records of GLOF events so far in Nepal, Tibet and Bhutan. Recent satellite imagery has revealed that there has been a significant increase in the number and size of glacier lakes, with 676 lakes identified as expanding since 1984, posing a direct threat to downstream communities in the event of a burst or overflow. 70% of India’s agriculture relies on glacier meltwater. In addition, there is a health risk too; releasing ancient viruses and bacteria locked in ice will lead to infecting wildlife and zoonotic diseases. Melting glacier water may carry toxic contaminants used in the past. The expected mean temperature rise could be anything in the range of 1.4 to 5.8 degrees Celsius in the world in the coming years, and in the Indian subcontinent, the rise may be between 3.5 and 5.3 degrees Celsius. Alpine glaciers have shrunk by 40% in area and by more than 50% in volume since 1850. Similarly, if Greenland ice sheets were to melt completely, sea level would rise by 20 feet. At the moment, sea level is rising at the rate of 0.74 mm per year.

The chief reason for the melting of glaciers is the increase in carbon dioxide concentration in the atmosphere along with other GHGs produced by human beings’ undesirable activities in industries, transport, and deforestation; more remarkably, the burning of fossil fuels for power production is responsible for warming our planet. Carbon blacks and other pollutants that settle on glaciers’ surfaces, reducing their albedo (reflections) effects, increase heat absorptions. The other potential driving causes are hydrological changes such as precipitation patterns due to climate change exacerbating both flooding and drought conditions. Switching over to renewable clean energy, efficient usages of energy and water management, afforestation, and reducing, recycling, and reusing are a few measures to reduce carbon footprints.