Climate change is high on the agenda at the G7 summit in Cornwall but progress to limit the rise in world temperatures remains painfully slow. Yet it was in 1938 that the first evidence came to light that the climate was warming because of rising levels of carbon dioxide pollution. This discovery was all the more remarkable because it was made by Guy Stewart Callendar, a steam engineer by profession who spent his spare time studying climate data. By the 1930s Callendar was collecting temperature recordings from 147 weather stations around the world, a unique project. And when he compared this to historical measurements of carbon dioxide he

Source: The Times June 13, 2021 23:03 UTC