These images show the Imperial Valley, on the border of California and Mexico. The international border is plain in the images because of the different intensity of vegetation, shown in bright green. These images also show the Salton Sea and the growing cities of El Centro, Calexico, and Mexicali.
This valley, also known as the Salton Sink, the Salton Basin, and the Salton Trough, is actually an extension of the Gulf of California, cut off from the Gulf by the Colorado River’s delta fan. The valley was renamed Imperial by turn-of-the-century land investors. The area south of the U.S.-Mexico border is known as the Mexicali Valley.
At the bottom of the sink lies the Salton Sea, the largest lake in California. It lacks an outlet to the ocean and lies 70 m below sea level. About 85% of the sea’s inflows come from agricultural runoff, and its waters are 37% saltier than the Pacific Ocean.
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