1934 Had Worst Drought of Last Thousand Years-We Made It Worse
“It was the worst by a large margin, falling pretty far outside the normal range of variability that we see in the record,” said climate scientist Ben Cook at NASA’s Goddard Institute for Space Studies in New York. Cook is lead author of the study, which will publish in the Oct. 17 edition of Geophysical Research Letters.
Two sets of conditions led to the severity and extent of the 1934 drought. First, a high-pressure system in winter sat over the west coast of the United States and turned away wet weather - a pattern similar to that which occurred in the winter of 2013-14. Second, the spring of 1934 saw dust storms, caused by poor land management practices, suppress rainfall.
“In combination then, these two different phenomena managed to bring almost the entire nation into a drought at that time,” said co-author Richard Seager, professor at the Lamont-Doherty Earth Observatory of Columbia University in New York. “The fact that it was the worst of the millennium was probably in part because of the human role.”
..”We found that a lot of the drying that occurred in the spring time occurred downwind from where the dust storms originated,” Cook said, “suggesting that it’s actually the dust in the atmosphere that’s driving at least some of the drying in the spring and really allowing this drought event to spread upwards into the central plains.”.