Quadishaya Reservoir Elevation and Water Storage between 2003 and 2009
<ul><li>The first graph shows the elevation of the water in that reservoir between January 2003 and December 2009. The elevation is a proxy measurement for the total volume of water stored there; labels show the water elevation at the time of the satellite images.</li>
<li>The second graph shows the water storage for the entire study area as measured by GRACE from January 2003 to December 2009. The gray line depicts total water storage in the region—groundwater, surface water bodies, and soil moisture—while the green line depicts changes in surface water. The difference between those two lines reflects the change in water stored in underground aquifers (ground water). The total water storage shows a seasonal fluctuation, but also an overall downward trend, suggesting that groundwater is being pumped and used faster than natural processes can replenish it.</li></ul>
NASA
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