We all must be known to the fact that the world comprises 70 percent of water and 30 percent of the land, out of which only 2.5 percent of it is fresh water. Even then, only 1 percent of it is easily accessible, as much of it (1.5 percent) trapped in snowfields and glaciers.
In the Himalaya, water flows along a narrow river, near the base of Gangotri Glacier. The pebbles found in small rivers flow and stream as they move downstream. The fresh water is flowing thousands of miles, usually to feed farms, people, the vast natural world, and dry plains. Over 200 million people in the downstream primary depend on water that comes from this stream and other sources.
The frequent changes in climate are affecting those high mountain regions, which is putting the “water towers” and billions of people that rely on downstream in even more precarious situations. The newly-formed research team has identified the most vulnerable and vital water towers across the globe. A Climate and Glacier Scientist at the University of British Columbia, Michele Koppes was quoted saying:
“We all need water. We’re 90 percent water. We require fresh water. We have big demands on the water from these water towers, and we have to understand better how they’re changing.”
Importance of Water Towers
The high mountains base more snow and ice in their peaks than exists anywhere on this planet besides the poles. Over 200000 glaciers, wetlands, piles of snow, and high-elevation lakes: All in all, the high mountains contain around half of all the fresh water for the use of humans.
Water Towers Located Across the Globe
Take a glimpse at the most significant mountains and glacial regions across the world, which serve as “water towers” for billions of people living downstream.
The icy and snow glaciers that cover the high mountains play a crucial role for around 1.6 billion people, which is nearly 20 percent of the human population on Earth. Our drinking water may have come from the high-mountain sources. These “water towers” are also treated as giant storage tanks, and it works like- starting with the snow falls, filling the storage tanks, and then gradually melts out over days, weeks, months or years.
This system matters to those who live in the high mountains as slow and steady melting of snow is less destructive than significant rain events, which leads to landslides or flash flooding. However, consistent water flow is suitable for farmers both up and downstream, who depend on steady water supplies. It is also crucial for towns and cities, which need fresh water for drinking throughout the year, even for the natural world, since the high mountains are home to nearly a third of the world’s land-based biodiversity. Mountain and Climate Scientist Walter Immerzeel at the University of Utrecht was quoted saying:
“In the past, mountains were not seen as one of the key parts of the Earth System, like tropical forests or oceans. But now we recognize them as just as important.”
Rising of Stress Level
Since years scientists have underlined that the frequent climate changes will affect the amount of fresh water stored in the “water towers” and the path of its flowing downstream. The high mountains are warming more faster than the average temperature of the world - temperature raises upto 2 degrees Celsius - compared to an average of around 1 degree Celsius.
Even small changes in the amount of water will add high stress to humans as they are already struggling with the supply of water. However, no one yet had quantified the relative need of each water tower in the world. The water supply system is affected due to increasing development, changes in climate, geopolitical instability, the associated rise in the use of water, and more.
Scientist Justin Mankin said that “this is really ringing a bell about the sensitivity of these mountain regions to climate change and other stresses.”
The research team further evaluated that the ‘importance of water towers’ depends on two main factors - the demand downstream, and the supply in high elevation areas.
Out of the five most significant water towers in the globe, three are in Asia- the Tarim, the Indus, and the Amu Darya. In South America, the Patagonian Andes, the Cordillera Patagonica Sur, and the Cordillera Principal rank most important, whereas, in North America, the Pacific Northwest’s Columbia Water Tower Regions and British Columbia’s Fraser River rank are highly relevant. In Europe, the Alps offers crucial supplies of water. However, Australia and Africa do not appear on the extensive list as their snowy mountains do not provide a critical source of water, just like the high mountains of South America, North America, and Asia does.
Future Stress Seems More Devastating
The drastic changes in climate will affect the shape and size of glaciers in the high mountains, along with the type and amount of precipitation that falls. In most of the cases, the amount of rainfall from the sky might increase but not necessarily enough to complement the loss from melting glaciers.
At the same time, the downstream demands and conflicts are expected to increase in around every “water towers” across the globe. A rapid growth in population rate is also likely to result in an exponential increase in demand for water. This increased dependency, along with limited government effectiveness and political turmoil over water rights in several parts of the world, make water towers more vulnerable.
The Indus is the most vulnerable “water towers” in the world, besides the Ganges, the Amu Darya, the Syr Darya, and the Tarim. “Water Towers” in South America are also extraordinarily fragile. Europe and North America are also not exempt from the pressure, which relies upon water towers regions like the Colorado River Basin, the Columbia Plateau, the Po, the Rhone, and more.
Justin Mankin said, “Water twoer vulnerability isn’t something that’s relegated to the water towers of high mountain Asia - this is something that spans both hemispheres and is really a global phenomenon.”
Matter of Concern
For decades, scientists have been known to the fact that changes to the high mountains are approaching the world. Imperial College London’s Hydrologist Wouter Buytaert says,
“The water is almost certainly going to change. So the next step is thinking about what can be done, how communities can be made more resilient. It is to be creative and find other solutions to offset some of that loss of water storage.”
In Ladakh, it is required to build stupas or small piles of ice that will last throughout the dry seasons. In Peru, it would require re-activation of the ancient water system, which stored water tower liquid into reservoirs and channels.
However, it also indicates something bigger by addressing geopolitical and climate change questions to keep the vulnerabilities in check.
Koppes further stated that it is crucial for humans to re-think about the whole world at this time.
“It’s critical for the developing world and the global south - but these vulnerabilities also exist in our own backyards, and need attention right now.”
Source: National Geographic