A new study finds that climate breakdown is shrinking the amount of time people can safely go about their lives, with a third of the world's population now in areas where heat severely limits activity. The research, led by scientists from the Nature Conservancy, was published in the journal Environmental Research: Health on Tuesday. Rising temperatures, driven by the continued burning of fossil fuels, are making it difficult even for many young, healthy adults to do basic physical activities during daylight hours at the height of summer.
The limitations are greater for elderly people, who have less ability to sweat and thus control their body temperatures. On average, people over 65 now experience about 900 hours each year when heat severely restricts safe outdoor activity, compared with 600 hours in 1950. Worst-affected are those in poorer countries or regions, even though they are far less responsible for climate breakdown than wealthy consumers.
In some tropical and subtropical regions, heat restricts outdoor activity for older adults for between one-quarter and one-third of the year. The most severe challenges are found in south-west Asia, south Asia, and parts of west Africa. Within countries there are huge variations according to geography, income group and types of work.
For example, in India, limitations are most pronounced across the Indo-Gangetic Plain and eastern lowlands, and least evident in the Western Ghats and the Himalayan foothills. In South America, people in the Amazon basin are far more vulnerable than in the Andean highlands. In many Gulf states, wealthy people can ease risks with air conditioning, while poorer migrant workers are exposed to dangerous levels of solar radiation on construction sites and while doing other outdoor jobs.