Man-made climate change directly influenced the historic storms that battered southern England in the winter of 2013-2014, submerging parts of the country and causing more than $900 million in damages, says a new study by European scientists.
The study also calculated that human-induced carbon emissions caused a whopping 43-per-cent increase in the risk of the once-in-a-century rainfall event.
Published in the journal Nature Climate Change on Monday, the study comes on the heels of another series of destructive storms that hit England repeatedly last month, and again as recently as last week.
The study concluded the heightened risk for extreme rainfall in England was caused by an increase in the water-holding capacity of the atmosphere and an abnormal positioning of the jet stream, both of which are linked to climate change.
“A major conclusion of our study is that the thermodynamic effect (atmosphere’s water-holding capacity) contributed two-thirds to the increase in risk of the event whereas the dynamic effect (the jet-stream positioning) contributed the other one-third,” said Neil Massey, the lead author of the study and a climate modeller at the University of Oxford in England.
The possibility that human-induced climate change contributed to the storms was thoroughly discussed in their aftermath.
Climate scientists say, as they predicted, extreme heatwaves and heavy storms are already more intense and happening with increasing regularity worldwide as the Earth warms up.
For Adam Fenech, director of University of Prince Edward Island’s Climate Lab, more and more studies are now showing mounting evidence linking extreme weather events to climate change.
“It’s like having DNA evidence of climate change,” he said, adding the precision with which “you can point to the attributes and when you are able to tell people the amount of confidence you have in your attribution,” is the best part of such studies.
To figure out the impact of man-made carbon emissions, authors of this study modelled the weather for January 2014 with and without the human influence.
The storms in the winter of 2013-2014 — reportedly responsible for the wettest December and January since 1876 — led to the flooding of thousands of homes and swollen rivers. In Dawlish, a town in southern England, part of the seawall collapsed as waves slammed into it.
In England, scientists can study a single extreme weather event because of the existence of detailed climate models and regional maps.
In developing countries, it’s almost impossible to tell if extreme events have anything to do with climate change. In early December, more than 300 people died in southern India after experiencing the heaviest rains in a century.
Meanwhile, Massey said it’s too early to attribute the recent Storm Desmond to climate change, but points out that a preliminary study into the flooding associated with it “has shown that there has been an increase in (the) risk of the event associated with the thermodynamic effect but the dynamic effect has not been studied yet.”