Water has become a luxury item and it is our fault alone. This is the sad conclusion reached by a recent study conducted by NASA, based on the data obtained during the Grace mission (Gravity Recovery and Climate Experiment), collected from 2002 to 2016.
Water has become a luxury item and it is our fault alone. This is the sad conclusion reached by a recent study conducted by NASA, based on the data obtained during the Grace mission (Gravity Recovery and Climate Experiment), collected from 2002 to 2016.
Fresh water is found in lakes, rivers, soil, snow, groundwater and ice and is one of the most important resources of the Earth, for drinking water and agriculture, and which also has repercussions on hygienic conditions and therefore on the public health.
But climate change, mainly due to human activities, and its unsustainable consumption have made this indispensable resource accessible to a few.
A research group from the Space Flight Center of NASA (USA), has used 14 years of observations from the Grace space mission to trace the trend of freshwater availability in 34 regions around the world and has shown that this is changing a lot and a lot quickly.
While the water reserves of some regions are relatively stable, others have experienced increases or decreases. And what's more, wetlands are becoming wetter, while drier ones are becoming more and more arid. A environmental disaster which is "concentrating" water only in certain areas of the planet.
“What we are seeing is a great one hydrological change - explains Jay Famiglietti of NASA's Jet Propulsion Laboratory, co-author of the work and collaborator of the GRACE mission - We observe a typical trend in which the wetlands of the world become wetter, those at higher latitudes and the tropics - while dry areas they wither more and more. In these areas we also observe several "hot spots" due to thedepletion of groundwater".
Famiglietti noted that while the loss of water in some regions, such as melting alpine ice and glaciers, is clearly driven by rising temperatures on the planet, it will take more time and data to determine the driving forces behind other patterns. freshwater change.
Photo: Nature
Changes in the availability of water on Earth: only green areas are likely to be less subject to climate change and direct human intervention
However, some hypotheses have been formulated. There is no doubt that groundwater levels are sensitive to drought cycles or persistent rain conditions, but also the pumping of groundwater for agricultural uses manifests a significant contribution to freshwater depletion around the world.
The researchers therefore believe that such a combination was likely to cause, for example, the significant groundwater depletion observed in California's Central Valley from 2007 to 2015. There is talk of a loss of 4 billion tons of water, which would easily fill 400.000 Olympic-sized swimming pools. When natural cycles led to less rainfall and reduced snow cover and surface water, in fact, people relied on groundwater more heavily.
The problem of water availability is (unfortunately) not new. According to a report by the World Health Organization and Unicef, published in 2017, about 30% of the world population, equal to 2,1 billion inhabitants, does not have continuous and safe access to drinking water, while 60 % of the population (4,4 billion people) does not have access to adequate sanitation.
The NASA study, published in Nature, is therefore configured as a sad confirmation and warning about the future, which, without a change of course, will only get worse. L'water emergency it is truly one of the environmental challenges of the century, which we are all called upon to overcome together.
For more information on the problem of water in the world, read also:
- Over 900 children are dying of hunger, the specter of famine returns to Somalia
- Nestlé: stop the hoarding of water in Pakistan, the petition
- Is Nestlè stealing water from American Indians (and others)?
Roberta de carolis
Cover photo: NASA's Scientific Visualization Studio
