Underground aquifers around the world are being dramatically depleted of fresh water, according to two new studies by U.S. researchers.
California’s depletion of its aquifers is in line with other regions of the world running out of water.
Twenty-one of the world’s 37 largest aquifers “have passed their sustainability tipping point,” reported Todd Frankel forThe Washington Post. This simply means that more water is being removed than replaced from the underground reserves of water.
The calculations are that on average from year to year 35 percent of the water used by humans worldwide, including use for crop production, comes from underground aquifers.
A report issued by NASA showed changes in aquifer water levels from 2003 to 2013. The mapping and water reserves levels are based on satellites measuring underground water, which exerts different gravitational pull based on volume. Water is exceptionally heavy and exerts a greater pull on orbiting spacecraft,” wrote Frankel in explaining NASA’s report.
Although agriculture is blamed for high water use, some other activities can be blamed for groundwater depletion. An example pointed out is an Australian aquifer being heavily depleted because of mining activity.
U.S. aquifers’ volumes and depletion are a mixed bag.
Source: www.agprofessional.com