Satellite Studies Reveal Groundwater Depletion around the World
Access to freshwater resources has always been a critical need for human and all forms of life on Earth. With a world population estimated at just shy of 7 billion and growing, the UN Food and Agriculture Organization says agricultural production will need to increase 70% by 2050. As agriculture takes up most of human water use, that’s going to put vastly greater demands and strains on our water resources at a time when climate change is changing temperature and precipitation levels and patterns in ways that cannot be predicted at local levels but are likely to make this even more difficult to achieve.
One thing that has been determined is that groundwater levels have dropped in many places around the world in the past nine years, including across key agricultural areas, such as southern Argentina, western Australia and the western US, according to a pair of studies of satellite gravity monitoring data conducted by researchers at the University of California Center for Hydrologic Modeling in Irvine, Science News reports.
The GRACE Project
Groundwater depletion is especially pronounced beneath parts of California, India, the Middle East and China. Besides showing that water is being pumped out of underground groundwater aquifers faster than it’s being replenished, the results raise concerns that farming in particular is the primary cause, according to the Science News report.
The Gravity Recovery and Climate Experiment (GRACE), conducted jointly by NASA and the German Aerospace Center, has been taking monthly snapshots of global groundwater used in the two studies since 2002. GRACE data is especially useful in accumulating data across countries where governments do not maintain extensive networks of groundwater monitoring wells. While the US maintains an extensive nationwide network of such wells, countries, such as China, do not.
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