An extreme shift in the weather brought on by manmade emissions likely caused the torrential rains that flooded Paris last month, a new study says.
Researchers at the Laboratory for Climate and Environment Sciences (LSCE) in France said the likelihood of unusual heavy rainfall, such as the one that caused the flooding of areas along the Seine River in May, has doubled in the past five decades as a result of global warming.
They found that the probability of such extreme weather patterns happening had increased by more than 40 percent at the very least.
LSCE senior scientist Robert Vautard said the rainstorms that flooded the French capital recently can be tied directly to the impacts of global warming on the Earth.
During the three days of heavy raining, the water in the river Seine reached 6.07 meters (19.9 feet), which is the highest point it has ever been in the past three decades. The overflow from river tributaries forced thousands of people living in nearby towns to be evacuated.
Torrential rains also caused widespread flooding in southern Germany, which destroyed several houses and vehicles. Reports say at least 18 people were killed in subsequent flooding in four European countries.
The researchers, however, were not able to retrieve evidence from the heavy rainfall in Germany that it is strong enough to establish its potential connection to global warming.
Despite this, the researchers believe that climate change may have also played a crucial role in the torrential rains in Germany. This only means that their observations were not in line with the climate models used, which would have allowed the researchers to draw robust conclusions similar to those from France.
Climate scientists have found it difficult to establish a connection between extreme weather patterns, such as droughts and superstorms, and the impacts of climate change, which can take hundreds of years to measure.
Warming of the Earth's Atmosphere
Richard Black, head of the London-based advocacy group Energy and Climate Intelligence Unit, explained that researchers are now able to make similar judgments such as provided by the LSCE study.
He said that we now know that the heatwave in Europe and the heavy rainfall in the United Kingdom, which both occurred just last year, were made more likely because of climate change.
Both events can be attributed to basic physics. As the atmosphere continues to become warmer, the more it is going to be able hold and discharge rainwater.
Recent measurements show that the average surface temperature of the Earth has increased by as much as 1 degree Celsius (1.8 degrees Fahrenheit) as a result of manmade warming.
If current trends continue, the temperature of the planet could rise up to 2 degrees Celsius (3.6 degrees Fahrenheit). This assessment takes into account efforts by national governments to reduce carbon emissions around the world.
Satellite readings conducted for the past 25 years show that water vapor levels in the Earth's atmosphere have also increased by as much as 4 percent.
This means that western and central Europe could continue to experience record-breaking rainfall events in the coming years.
The findings of the Laboratory for Climate and Environment Sciences are set to be featured in the journal Hydrology and Earth System Sciences.