Humans Are Driving Alarming Fluxes In Freshwater Sources, Says NASA





An ambitious study of the state of Earth’s freshwater sources has concluded that dry regions have gotten dryer and wet regions have gotten wetter over the past 14 years – and yes, you can bet that we humans had a big role to play.


Decades of past research have demonstrated that the climate cycles maintaining freshwater in all its forms – flowing in lakes and rivers or stored in groundwater reservoirs and glaciers – are being disrupted by anthropogenic activities. Furthermore, large-scale water extraction and diversion operations, undertaken to meet the ever-growing demands from agriculture, industrial processes, and expanding urban populations, are depleting the planet’s stores at unsustainable rates.


Altogether, it is estimated that nearly 80 percent of the world’s population live in areas extremely threatened with impending water insecurity, and two-thirds of the world’s freshwater habitats are at risk of irrevocable change.


In order to form the most effective plans for mitigating a dystopian future, scientists need accurate assessments of the current state of freshwater. And though this can be done easily on a region-by-region basis, quantifying it on a global scale is, understandably, quite difficult.


Luckily for humanity’s sake, leaping fearlessly into massive datasets is what researchers at NASA do best.


The team’s comprehensive model, published in Nature, reviewed satellite-based precipitation observations from the Earth System Science Interdisciplinary Center’s ongoing Gravity Recovery and Climate Experiment (GRACE) mission, Earth surface images from NASA and the US Geological Survey satellites, and published reports about agricultural, mining, and hydrological operations from across the world.


Their analysis shows changes to 34 regions, covering major areas of every continent, occurring between 2002 and 2016.


Trends in TWS (in centimeters per year) obtained on the basis of GRACE observations from April 2002 to March 2016. The cause of the trend in each outlined study region is briefly explained and colour-coded by category. Image and caption credit Rodell et al./Nature, 2018










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