Periods of extreme drought can be a normal part of global climate patterns, but rising temperatures may now be changing some regional climates for good
‘Bathtub ring’ mineral deposits are visible due to extraordinarily low water levels at the Elephant Butte Reservoir in New Mexico
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Exceptionally severe and persistent droughts – or megadroughts – have wreaked havoc on human societies for thousands of years. A megadrought in northern China between AD 1627 and 1643, for instance, caused a famine that killed an estimated 20 million people and may have sparked a revolt that toppled the Ming Dynasty.