A study has found that the average length of heat waves in Western Europe has double since 1880. The study also found that over the same period the number of extremely hot days has tripled.

One of the things the study had to account for was the so called “warm bias” in historical measurements. Measurements taken before shielding of thermometers became standard practice were recorded as being higher than they actually were.

Accounting for this, and a other biases in recording summer temperatures, the study has found that apart from the heat waves variability of summer weather has also increased. Scientists are concerned that future extreme weather events could have significant adverse environmental and economic effects.

Read more on this story from the BBC