Fresh water is disappearing and much of the world is getting drier

Researchers identify western U.S. and Central America as one of four 'mega-drying' regions

- BY IAN JAMES AND SEAN GREENE

CALIFORNIA'S Central Valley, where citrus, above, and other crops are grown, is rapidly losing groundwater.

For more than two decades, satellites have tracked the total amounts of water held in glaciers, ice sheets, lakes, rivers, soil and the world's vast natural reservoirs underground - aquifers. An extensive global analysis of that data now reveals fresh water is rapidly disappearing beneath much of humanity's feet, and large swaths of the Earth are drying out.

The 'mega-drying' regions include large parts of Canada and Russia, southwestern North America, Central America, the Middle East to northern China and Southeast Asia, as well as a giant interconnected drying region that spans from North Africa to Europe.

Scientists are seeing "mega-drying" regions that are immense and expanding — one stretching from the western United States through Mexico to Central America, and another from Morocco to France, across the entire Middle East to northern China.

There are two primary causes of the desiccation: rising temperatures unleashed by using oil and gas, and widespread overpumping of water that took millennia to accumulate underground.

"These findings send perhaps the most alarming message yet about the impact of climate change on our water resources," said Jay Famiglietti, a hydrologist and professor at Arizona State University who coauthored the study. "The rapid water cycle change that the planet has experienced over the last decade has unleashed a wave of rapid drying."

Since 2002, satellites have measured changes in the Earth’s gravity field to track shifts in water, both frozen and liquid.

What they sent back shows that nearly 6 billion people — three-fourths of humanity — live in the 101 countries that have been losing water.