An Oxford University study published in the British journal Nature Sustainability warns that nearly half of the world’s population could suffer from extreme heat by 2050 if fossil fuel use continues at the current rate. The research, based on a projected two-degree Celsius rise in global temperature from pre-industrial levels, found that 41 percent of people—about 3.79 billion—would be exposed to dangerous heat, up from 23 percent in 2010.

The study, led by Dr. Jesus Lizana of Oxford’s Department of Engineering Science, highlights a sharp contrast between national temperature averages and actual living conditions. It identifies India, Nigeria, Indonesia, Bangladesh, Pakistan, and the Philippines as particularly vulnerable to severe heat exposure. The findings also show that regions with high population density will experience over 3,000 cooling degree days, indicating a growing demand for air conditioning and other cooling systems.

Researchers noted that extreme cold conditions will decline globally, with the share of “severely cold” populations dropping from 14 percent to 7 percent. This shift will increase cooling needs in tropical countries while reducing heating requirements in northern nations such as Canada and Russia.