Increasingly warm and humid conditions that are predicted in the coming decades could slash worker productivity 10 percent worldwide by mid-century and could eliminate worker capacity altogether in some regions during the hottest months, a new U.S. study predicts. In an analysis of labor capacity based on existing military and industrial heat stress standards, researchers from the National Oceanic and Atmospheric Administration (NOAA) found that the amount of work that people can do in some regions has already dropped by 10 percent over the last six decades and that the lost labor capacity could double by 2050 based on global warming projections. According to their analysis, published in the journal Nature Climate Change, a temperature increase of 6 degrees C (11 degrees F) would “eliminate all labor capacity in the hottest months in many areas,” including the U.S.’s lower Mississippi Valley. “This planet will start experiencing heat stress that’s unlike anything experienced today,” Ronald Stouffer, co-author of the study, told Reuters. According to the study, temperature increases must be limited to less than 3 degrees C (5 F) to maintain labor capacity in all areas during the hottest months.