Even though climate change is bringing more frequent and severe heat waves, there is no standard, global way to measure heat-wave severity, and existing indices have different thresholds for defining dangerous heat-stress conditions. Even though climate change is bringing more frequent and severe heat waves, there is no standard, global way to measure heat-wave severity, and existing indices have different thresholds for defining dangerous heat-stress conditions. Earth Sciences Environment Phys.org – latest science and technology news stories