Posted 11 февраля 2022,, 09:38
Published 11 февраля 2022,, 09:38
Modified 24 декабря 2022,, 22:38
Updated 24 декабря 2022,, 22:38
Experts from the French Institute of Geological Sciences and Dartmouth College, who conducted the research, note that two key factors are bringing the problem of global thirst closer: population growth and climate change. And the first issue that needs to be addressed is finding a balance between the ratio of the number of people living on the planet and the finite volume of available water supplies.
Using new satellite imaging techniques, scientists have measured the thickness and movement of more than 250,000 mountain glaciers for the first time, Bloomberg reported. For analysis, they used almost 812 thousand pairs of high-resolution photographs and covered 98% of the Earth's territory covered with glaciers. The experiment was carried out from 2017 to 2018.
Based on the data obtained, it was possible to more accurately determine the volume of ice contained in glaciers. First of all, dramatic changes have been found in the volume of ice and fresh water supplies on which hundreds of millions of people depend for drinking water, agriculture and electricity generation.
Interestingly, the glaciers of the Himalayas contain 37% more ice than previously thought. For the eight million inhabitants of the Indus and Chenab basins in the Himalayas, this is good news - glacier meltwater provides more than half of the river's flow during dry seasons.
“But the fact of the matter is that the Himalayas are an exception. Almost everywhere in other places we found thinner ice,” said one of the authors of the project, Professor Mathieu Morligem. “For example, the Andes contains 27% less ice than scientists have always thought”.
By the way, earlier it was found that the catastrophic thinning of the ice on Everest began. There, the glacier loses two meters of ice per year.
Researchers have had to lower previous estimates of the contribution of mountain glaciers to sea level rise. It has already been calculated that if all glaciers, with the exception of the large ice sheets in Greenland and Antarctica, melt, then the level of the world ocean will rise by about 25 cm, and not by 33, as previously thought.
"That doesn't change the fact that glaciers are melting faster and faster, though", - the lead study author Romain Millan said in a statement. He clarified that the new estimates are largely due to changes in the way ice volumes are calculated.
On the other hand, there is no escape from the problem of global warming. Because of this, there is an expansion of arid zones in certain regions of the world and the formation of new deserts. This is a natural consequence of the reduction and even complete disappearance of the necessary water resources.
The second important aspect is related to the violation of the hydrological cycle on the planet, the change in the seasonality of precipitation, as well as the rise in the level of the world ocean, which is fraught with the flooding of fresh water sources with salt water. It is known that 2/3 of the volume of fresh water is concentrated in glaciers, which are rapidly melting due to global warming.
French scientists have come to an unequivocal conclusion: the reduction in the total volume of ice will inevitably have an impact on the Earth earlier than expected. Experts do not lose hope that their forecast will influence the decisions of the leaders of the leading powers on the construction of water supply infrastructures.
It is no secret that a person without food can survive for almost two months, but without water - a maximum of a week.
According to the FAO, environmentalist Jan Drazhnitsky reminded Novye Izvestia, huge volumes of fresh water are used in global agriculture, mainly for irrigating fields. At the same time, different plants require different amounts of water, and half of the precious resource goes to supply fodder grains for livestock. Another 20% of fresh water is used by industry, and only 8% is used for domestic consumption.
- With the growth of the world's population, the demand for agricultural production will also increase. True, over the past decades, there has been a slowdown in the growth in the level of water withdrawal from fresh lakes and rivers to provide agriculture and industry, but this figure is still ahead of the growth rate of the world's population, which was established back in the 1940s. Here is just one example. India has recently increased access to clean water supplies in rural areas but still tops the list of H2O deficient countries in terms of population. More than 160 million people do not have free access to clean water there , - expert Drazhnitsky noted
However, UN specialists do not agree with the ecologist, who argue that the reasons for the lack of water resources are explained by the imperfections of the economy, infrastructure and supply chains.
Modern technologies, according to scientists from the French Institute of Geological Sciences, can effectively deal with the threat of scarcity, but their implementation is not cheap.
The current rate of aggravation of the water crisis can lead to the fact that already in 2050 more than 2/3 of the world's population will live in regions where the shortage of fresh water will begin to be felt at least once a month. Rapid industrial development will lead to a 50% increase in fresh water consumption by 2040.
Experts have long come to the conclusion that without the development of alternative methods and technologies that allow desalination of sea water in large volumes, humanity in the future will have to rely only on those fresh water reserves that will remain on the planet by that time.
In Israel, for example, the only Lake of Tiberias is no longer able to meet the demand for drinking water that the country's population makes. That is why, anticipating the problem, a program for desalination of salt water began to be implemented there. This allowed a country in a notoriously disadvantaged - in terms of drinking water supplies - to solve the problem in advance and become a world leader in such technologies. In the future, this system promises to be one of the most promising in the world, especially given the steadily increasing demand for clean water and the reduction of world reserves in freshwater reservoirs.
According to the World Water Commission, today every person needs 20 to 50 liters of water daily for drinking, cooking and personal hygiene.
There is a lot of fresh water on Earth, but it is unevenly distributed across continents and countries. Sometimes this causes water conflicts that turn into military clashes. For example, the Arab-Israeli conflict over access to the Jordan River in the dry year of 1964. In 1971, an Indo-Pakistani conflict broke out over the use of the waters of the Indus River, which flows through the territory of these two countries. There were armed clashes in Africa over the Nile and Okavango rivers.
In addition to the scarcity of fresh water in certain countries, there is another big problem - the pollution of rivers and natural reservoirs. It occurs due to industrial emissions, sewage, due to the washout of chemical fertilizers and various herbicides and pesticides from the fields.
As coralreef-aqua.ru reported , hydro resources are distributed unevenly across the globe. The scatter is observed both across countries and continents, and across climatic zones.
Of all the continents, Asia has the largest water resources - 14,600 km3, the smallest - Australia and Oceania: 1,600 km3.
If we take into account only rivers, lakes, shallow soil layers and determine the volume of reserves by the number of river flows per year, then Latin America is best provided with water. There is an extensive river network, predominantly a climate with an abundance of precipitation.
Brazil is considered the leader in water resources. On its territory flows the most full-flowing river in the world - the Amazon.
Among the leaders is Russia, where there are also many large rivers, it owns the water area of the largest freshwater reservoir - Lake Baikal.
Russia is followed by Canada, China, Indonesia, USA, Bangladesh, India, Venezuela, Myanmar.