The western drought is bad. Here’s what you should know about it.
By Henry Fountain
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Much of the Western half of the United States is in the grip of a severe drought of historic proportions. Conditions are especially bad in California and the Southwest, but the drought extends into the Pacific Northwest, much of the Intermountain West, and even the Northern Plains.
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A drought usually starts with less-than-normal precipitation (and what is normal varies from region to region). If the dryness persists, river flows and reservoir and groundwater levels start to decline. Warm temperatures have an impact, too, causing winter snowpack to melt faster, which can affect the availability of water throughout the year. Excessive heat also causes more evaporation from soils and vegetation, which can lead to crop failures and increases the risk of severe wildfires.
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The drought has persisted for so long in the Southwest that some scientists say a megadrought is emerging in the region, one that is similar to, or perhaps worse than, some that have occurred over the last 1,200 years and lasted for 40 years.
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