Worldwide, fresh water resources are not equitably distributed. However, he was known to be rather persistent. There were, because researchers are telling us today that 10 years ago fresh water levels suddenly dropped!
Water is essential for life. And on land, it’s good, it covers about three-quarters of the surface. The problem is that less than 3% of this water is usable. Less than 3% is found in the form of so-called fresh water, which must be found in glaciers, groundwater, rivers or lakes. And today an international team is giving alarming news on this subject. In the magazine Surveys in GeophysicsThe researchers describe how satellite observations provided them with evidence that the total amount of fresh water on Earth decreased sharply in May 2014. Since then, it has remained at a low level.
To reach this conclusion, the researchers worked on data sent back by the Grace satellites.Gravity Recovery and Climate Experiment). Their instruments make it possible to measure fluctuations in it. GravityGravity Shows changes in ground barley. On a large scaleOn a large scale Water, above and below ground. All on a monthly basis.
More droughts and less water
Between 2015 and 2023, these measurements show that the average amount of fresh water stored on land – considered surface water liquidliquid Water in lakes and rivers – as well as underground aquifers – was 1,200 cubic kilometers below average levels from 2002 to 2014. “It’s two and a half times. VolumeVolume of Lost Lake Erie »explains Matthew Rodel, hydrologist at GSFC, Goddard Space Flight CenterGoddard Space Flight Center Of NASANASAin a press release.
The researchers report that it all started with a massive drought that hit Brazil. Then, Australia and Asia experienced a series of major drought events. But also in South America, North America, Europe and Africa. Warming of ocean temperatures in the tropical Pacific from late 2014 to 2016, culminating in an event the childthe child The largest since the 1950s, has led to changes in atmospheric jet streams. As a result, climatic conditions and rainrain Revised worldwide. Even after the end of El Niño, global freshwater reserves failed to replenish.
A link between falling freshwater levels and global warming?
The work shows that 13 of the 30 most severe droughts observed by GRACE occurred after January 2015. It shows that Global WarmingGlobal Warming May contribute to chronic depletion of fresh water resources. How? Because with climate change, sometimes it can take a long time before a rain event occurs. Even if the rain is more intense – because the heat increases.EnvironmentEnvironment To retain more water vapor – dry soils absorb less water which is lost instead of recharging underground aquifers.
For the moment, it is difficult for scientists to establish a definitive link between the two. However, the nine warmest years in modern history have coincided with a rapid decline in freshwater supplies. “We don’t believe this is a coincidence and could be a trigger for what’s to come.”r,” concluded Matthew Rodel. That is, a phase of persistent drought for all of our Earth’s continents.
