Share to ClassroomDelhi Ground Hits 64C, Hotter Than Air
Delhi has had a long heatwave. On Tuesday, the India Meteorological Department (IMD) said the air temperature reached 43.5C. But the ground was much hotter. Researchers from the group Greenpeace India used a thermal camera — a camera that measures the heat of surfaces. They found ground temperatures as high as 64C in sunny places. Under a busy bridge in south Delhi, sunny ground reached 64C, but shaded ground was only 42C.
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.
