U.S. average temperature has increased by about 1.5° F (0.8°C) since 1895—and notably, more than 80% of this increase has occurred since 1980. The most recent decade was the nation’s hottest on record, and the warming will continue—the report estimates that U.S. temperatures will rise by 2° to 4° F (1.1°C to 2.2° C) over the next few decades. Of course, the amount of warming will depend on the sensitivity of the climate system — something that remains up for debate — and the rise or fall in carbon emissions we’ll see in the future. Under a high emissions scenario — if the world isn’t able to curb the use of fossil fuels — we could see warming as high as 10° F (5.5° C) by the end of the century. Climate change will increase the likelihood of water shortages and competition for water, especially in arid but growing areas like the U.S. Southwest. Spring snowpack is on the decline in the mountain West, and we’ll see more seasonal water shortages throughout the country — even in areas where total rainfall will increase. Some good news: over the next 25 years, the agricultural sector is predicted to be relatively resilient to changes in the climate, including rising temperatures and more sporadic rainfall. That’s important to remember. U.S. farmers have always been the best in the world at getting the most out of their land, but it’s also true that there’s a ceiling to adaptation, and by mid-century, yields of major U.S. crops are expected to decline — seriously bad new for the U.S. and those who depend on American farmers.
via science.time.com
