LONDON- Extreme summers and scorching heat waves similar to the one that killed anestimated 20,000 people across Europe last summer could become more frequent inthe future, climate scientists said.
Last summer’srecord-breaking temperatures were very unusual but global warming and anincrease in climate variability means more heat waves are likely in years tocome.
“It is likely that these types of events will become more common,”Dr. Christoph Schar, of the Swiss Federal Institute of Technology ETH Zurich,told Reuters.
“Our simulations show that, roughly speaking, every second Europeansummer is likely to be as warm, if not warmer, than the summer of 2003.”
Summer temperatures change slightly from one year to another but they havebecome more variable with stronger fluctuations in temperature making it moredifficult to predict changes and more likely they will be extreme.
Schar and scientists at the Swiss meteorological service MeteoSwiss madesimulations of future climate from 2071 to 2100 using records from the past 150years and assuming that concentrations of greenhouse gases such as carbondioxcide from cars and factories would rise to twice their current level by theend of the century.
Their predictions are published online by the science journal Nature.
“By the end of the century we will still see some normal summers,looking from today’s perspective, but the mean would be more like 2003 and themaximum would be even warmer,” Schar added.
In some parts of Europe last summer’s temperatures were up to five degreesCentigrade (8 or more Fahrenheit) higher than normal over a period of threemonths.
Such a rise over a day or week is not unusual but over three months is rare.
“The previous record in Switzerland, in 1947, had been three degreesC,” said Schar. The searing heat wave is thought to have contributed to anestimated 13,600 extra deaths in August in France. In Italy, where the mercurysoared to 40 degrees Celsius (104 Fahrenheit), reports suggested deaths rose 20percent during the summer.
The elderly were most vulnerable to the extreme heat which also caused forestfires, crop losses and water shortages.
The World Health Organization has warned that the death toll from globalwarming will continue in coming years if current trends continue.