two men riding on the back of a motorcycle down a street

Photo by Johan Mouchet on Unsplash

Delhi Surfaces Hit 64C Despite 43.5C Air Reading

natureJun 20, 2026·334 words·3 min read

For several weeks, India's capital, Delhi, has endured a severe heatwave, with daytime temperatures routinely climbing above 40C. On Tuesday, the India Meteorological Department (IMD) recorded an official maximum of 43.5C. Yet that figure tells only part of the story. Researchers from the environmental group Greenpeace India spent the day moving through the city with a thermal camera, which recorded surface temperatures as high as 64C in exposed locations.

Air and ground temperatures are not the same. The IMD measures the air. The thermal camera measures roads, concrete and other surfaces. On hot days, these surfaces become much hotter than the air. They then send the heat back out, which makes people feel even hotter. The problem is worst in crowded cities with few trees. In one place, the ground was 61C in the sun but only 39.8C under a tree nearby.

The heat is dangerous. A lung doctor, Dr A Fathahudeen, said the normal body temperature is 37C. When it goes above 40C, the body cannot work well. This can cause tiredness, headaches and, in bad cases, organ failure. He told people to drink water, wear loose clothes, and not work outside in the afternoon. But poor people cannot stop. Street sellers said they must keep working. Inside many homes, the temperature stays near 40C.

Read at other levels

A1Beginner92w A2Elementary127w B1Intermediate219w B2Upper-Intermediate271wPro

C1Advanced334w(current · Pro)