Researchers have calculated that roughly 489,000 heat-related deaths occur each year, with 45 percent of the deaths in Asia and 36 percent in Europe.
For older adults with physical health problems, temperatures as low as 26.7°C (80°F) can pose significant danger. And when humidity is as high as 90 percent, even 25.6°C (78°F) can be hazardous, said Deborah Carr, a Boston University sociologist who specializes in the study of aging.
