NASA: 1934 Boasts Worst Drought in 1000 Years

The year of 1934 was a dry one, as it boasted the worst drought in North America in the last 1,000 years, a NASA study has found.

During the Dust Bowl days - also known as the Dirty Thirties - the 1934 drought was 30 percent more severe than its runner-up in 1580, and covered 71.6 percent of western North America. The average extent of the 2012 drought, for comparison, was 59.7 percent.

"It was the worst by a large margin, falling pretty far outside the normal range of variability that we see in the record," climate scientist Ben Cook at NASA's Goddard Institute for Space Studies said in a news release.

Two factors in particular set up 1934 for the perfect storm of rainless weather. First, a high-pressure system in winter hovered over the US's West Coast and turned away wet weather. And second, the spring of 1934 saw dust storms, caused by poor land management practices, which also suppressed rainfall by blocking sunlight and prevent evaporation that would otherwise help form rain clouds.