A new NASA study is painting a bleak and rather hot, not to mention somewhat waterless, future for the midsection of the United States — a decades-long megadrought before the turn of the century. Said megadrought is predicted to surpass in intensity and duration any drought that has visited the United States (and its portion of North America) in the last thousand years.
The Guardian reported Feb. 16 that, according to the study conducted by Benjamin Cook at Nasa GISS, things are going to get a lot worse with regard to water supply in the American Southwest and throughout the Plains states sometime around mid-century. Cook examined how hotter temperatures prevalent in the last decade has contributed to the current drought in California, noting how global warming has intensified the California drought by 36 percent. This is particularly important in that California hasn’t experienced a drought this bad in 1,200 years.
Cook found that global warming intensifies drought in a number of ways. Regular evaporation from soil and reservoirs increases. There is also an increase in water demand. Global warming also contributes more rainfall and less snow as precipitation, something that presents enormous problems for places like California that rely on snowpack melt to refill region-serving reservoirs throughout the year. Those increased temperatures also produce an earlier snowpack melt each year.
The study, which has been published in Science Magazine, centers of the ‘CO2 is plant food’ myth, which posits that more carbon dioxide in the atmosphere makes for more abundant agriculture. However, that isn’t the case. More carbon dioxide on a worldwide scale (such as the Earth is experiencing at present) only contribute to higher temperatures and more intense droughts.
As the Christian Science Monitor points out, it was just such a megadrought — a drought lasting for more than a decade — that brought to an end the flourishing Pueblo civilization in what is now the American Southwest nearly a millennia ago. All that is left of those populations are the stone dwellings at Mesa Verde, Chaco Canyon and other sites on the Colorado Plateau.
Cook and his co-author, Columbia University climate scientist James Smerdon, project that megadroughts will hit the main agricultural regions in the United States – along the Pacific coast in California and in America’s famed “breadbasket,” the Midwest. This, of course, takes into consideration that current carbon emissions into the atmosphere continue at present levels, causing hotter and hotter temperatures. Chronic water shortages are anticipated, making farming and ranching in the affected regions nearly an impossibility.
Still, the NASA study isn’t all doom-and-gloom. As its authors point out, the world has reached an important nexus in history, where better stewardship of the planet is not an indulgence but a necessity. Cutting carbon emissions can lessen the impact of hotter temperatures, ensure that droughts don’t become megadroughts in the future. And it is that point that the authors drive home: Reduce carbon pollution being dumped into the atmosphere and significantly reduce the coming devastating effects of global warming.