The Tibetan Plateau is home to the sources of major rivers and rivers in Asia. A recent study published in the journal Nature reveals that with global warming, the resources of “Asia’s water tower” are dwindling, increasing the risk of water scarcity.
Perched 4,000 meters above sea level and home to the roof of the world – Mount Everest, which culminates at 8,849 meters above sea level – the Tibetan Plateau is an important water resource for many Asian countries. Spread over 2.5 million square kilometers and comprising no less than 46,000 glaciers, this region of the world is also called the “ third pole since it is home to the third largest concentration of ice in the world, after the North and South Poles.
Like theArctic and theAntarcticthe Tibetan plateau is considered a hot spot climate, since it is dangerously affected by the effects of global warming. A team of researchers in China and the United States is sounding the alarm in a study published in the journal Nature and warn about the decrease in water stocks on the plateau.
” For the past twenty years, the southernmost glaciers of the plateau have been melting visibly. “, explains Professor Di Long, co-author of the study and researcher at Tsinghua University in Beijing. With an increasingly hot and humid climate, the tibetan plateau has been losing just over 10 billion tons of water per year since 2002 “. A melting of the ice which should continue since the researchers predict a rise in temperature of around 2°C in this region by the end of the century if there is not a consequent reduction in carbon emissions in the next ten years.
The risk of ” Sudden overflows of glacial lakes, already real, will threaten the safety of communities downstream from the glaciers “, also warns the latest report of the Intergovernmental Panel on Climate Change (IPCC). By 2100, the group of experts estimates that the runoff from a third of the major glacial catchments would be reduced by more than 10%, with severe consequences for the populations who depend on this water source.
►To listen: Melting ice: “In the year 2100, whatever the scenario, there will not be much left of the glaciers”
A threat to local populations
The Tibetan plateau hosts the sources of the main Asian rivers, including the Mekong, the Brahmaputra, the Indus, the Yangtze or the Yellow River and its waters flow into several countries including Pakistan, India, China, Nepal or even Bhutan.
In a scenario where carbon emissions remain at current levels, the researchers concluded that two river basins were particularly affected by the decline in their resources, the Amu Darya and the Indus: They are both major water towers for the countries of Central Asia, for one, and Pakistan and India in particular, for the other. In these regions, the drought and the decrease in water resources will have direct consequences for the populations downstream of the rivers and rivers. The risk is that there is not enough water for these people warns Di Long.
For this hydraulic engineer, the Amou-Daria could no longer be able to meet 119% of the current water demand, which would make the populations deficient in water. As for the Indus River, it will no longer be able to meet 79% of the needs of the current demand, a water shortage that could therefore affect two billion people.
Focus on other water resources
Faced with a potential water crisis, what are the solutions? For Michael Mann, one of the co-authors of this study and director of the Department of Science, Sustainable Development and Media at the University of Pennsylvania, interviewed by the BBC, countries around the Tibetan Plateau are likely to experience more dry spells, marked by less rainfall. For him, it is imperative to reduce carbon emissions, otherwise there will be no going back.
The study recommends that the various governments rely on other types of water supply both regionally and globally, and to do so collectively. Groundwater appears to be one of the solutions for anticipating possible shortages. ” Another option would also be to move water resources from other regions to areas affected by global warming on the Tibetan Plateau, but these are costly solutions. “says Michael Mann. And faced with these issues related to water resources, there are political issues around Asian waterways. Chinese lusts for example on the mekong river have already been the subject of geopolitical concerns and tensions in the region.
Behind the effects of global warming on the Tibetan plateau, it is the whole issue around water that is once again on the table. On the last World Water Day, which took place on March 22, the United Nations Special Rapporteur on human rights, drinking water and sanitation, Pedro Arrojo Agudo, believed that the greatest social risks arising from climate change were generated around water: “ Faced with increasing climate variability, the key to adaptation strategies lies in strengthening the resilience of the water cycle by recovering and conserving the functionality of the most inertial ecosystems of the water cycle: wetlands, riverbank ecosystems, river beds and above all, underground aquifers. »
Ensuring access to water for all
In 2010, the United Nations recognized that ” the right to safe drinking water and sanitation is a fundamental right, essential for the full enjoyment of life and the exercise of all human rights “. Water must be considered and managed as a common good.
In parallel with groundwater, the other solution, on a global scale, would lie in underground aquifers, strategic reserves to cope with the extraordinary droughts that climate change will harden. By preserving them, we would protect access to drinking water and sanitation for people living close to nature.
In 2019, 785 million people do not even have a basic drinking water supply service and 144 million of them have to use surface water. According to UNICEF and the World Health Organization, 1 in 3 people do not have access to safe water.
Today, nearly 2.2 billion people do not have access to water and 3.6 billion people worldwide live in areas where water is a potentially scarce resource at least one month a year. . Figures that will continue to increase as long as real adaptation to global warming is not put in place.
►To read: “Water will reposition itself among the priorities for security in the world”