Categories
Planet Care

330: Water monitoring satellites

Problem:

Studies have found that a third of Earth’s largest groundwater basins are being rapidly depleted by human consumption, despite not having accurate data about how much water remains in them.

That means significant segments of Earth’s population are consuming groundwater without knowing when it might run out.

In many parts of the world, little or no information is publicly available on how much water a given aquifer contains. It’s rare to know how much water people are withdrawing or how this relates to replenishment rates.

Solution

Satellites to reveal path to better water management.


Gravity Recovery and Climate Experiment (GRACE), twin satellites launched in March 2002, circling the Planet, always between 106 and 193 miles apart, have been providing invaluable assistance in managing natural resources on the ground.

The two satellites (nicknamed “Tom” and “Jerry”) constantly maintain a two-way, K-band microwave-ranging link between them.
GRACE has been generating weekly drought indicators at the National Drought Mitigation Center.

This information already is helping water users and policymakers manage scarce groundwater resources in California, the Tigris-Euphrates Basin and several other locations around the world. It is also providing an example of how satellites and remote sensing are reshaping the water world.

Agricultural yields in Syria and Iraq plummeted after 2007. Turkey — the upstream user — refused to release additional flows to the neighbouring countries, and water stress became so severe that some farmers abandoned their lands and migrated to Baghdad. As of this year, the region had the second-fastest rate of groundwater depletion on Earth, after India.

Researchers in Turkey at times refused to release their water-related data, citing security concerns. But the GRACE remote-sensing technology has created a bypass around the reluctance of many countries to release their data.

In 2018, the Gravity Recovery and Climate Experiment Follow On (GRACE-FO) satellites—a joint mission launched in 2018 by NASA and the German Research Center for Geosciences (GFZ) joined “Tom and Jerry” in the mission of detecting subtle shifts in Earth’s gravity field, caused by changes in groundwater storage or by the decay of ice sheets and glaciers.

Recent data shows that the planet’s surface mass in August 2020 deviated from the average for all months between 2004 and 2009. with some of the most dramatic changes focused in the ice-rich areas of West Antarctica, Greenland, and southeast Alaska. Scientists analyzing GRACE data found that mountain glaciers had lost about 200 gigatons of ice per year between 2002 and 2016, contributing 8 millimeters to global mean sea level.

Discover Solution 331: Synthesized dairy products

Support 366solutions on Patreon and receive the ‘366solutions Insider Newsletter’ with updates on the monthly progress and successes of published solutions.

Leave a comment