Floods, droughts, forest fires, tornadoes, mudslides. Extreme weather events are increasing in the United States since the beginning of the year, from Texas to California through Colorado.
The American media talk about “weather whiplash”. In meteorology, the term refers to the sudden change in one place, from one catastrophe to another.
As in Texas, where in the space of three weeks in April, the state has experienced drought and floods. During the month of May 9842 billion liters filled the Texas groundwater. The equivalent of what it would take, according NBCNews (see video below), to supply California for a year and a half. Oklahoma, Texas neighbor, has also not been spared. The capital, Oklahoma City has experienced a month of historical rainfall rates.
These torrential rains took a heavy toll in human lives: 31 people died, including 27 in Texas.
Meanwhile, on the West Coast, some Californians paint their green lawns, failing to water them. Since January, for the third consecutive year, the Golden State suffers a severe drought . From April 1, Governor Jerry Brown announced water restrictions by 25% in urban areas, a measure never taken yet on this scale.
Since the incidents – theft, stream diversions, siphoned trucks – multiply while blue gold becomes scarce.
Disaster that will multiply
This should not stop there. This type of prolonged drought episodes become more frequent, according to a report published in February by NASA . The US agency explicitly refers to emissions of greenhouse gases as the cause. Floods, hurricanes, cold spells and other natural disasters are also expected to increase.
To describe the influence of climate change on these events, Katharine Hayhoe, a climatologist at Texas Tech University, prefers the analogy with cycling, “As doping multiplies the capacity of the cyclist, climate change increases the frequency and magnitude extreme weather events that existed naturally, causing stronger hurricanes, more intense and more frequent heat waves, heavier precipitation. “
Climate change is therefore perceived in strengthening short and violent weather hazards, and felt less in the long run. “The climate models and observations consistently show that heavy rainfall of one or two days are ever more numerous and more powerful, and this through all the United States, including Texas, “said John Nielsen-Gammon, a researcher in atmospheric science at the University A & M, Texas.
The National Fire Center (NIFC) and the US Forest Service have also both warned of significant risks of forest fires this summer in California. These risks will extend in the coming months, on the West Coast to Seattle, and even across the country, in the southern states on the east coast.
This year is made, in addition, outstanding by the arrival of El Niño weather phenomenon. Appearing every two to seven years, resulting in rising temperatures in the eastern Pacific, causing their decline in across the ocean, and reverse the direction of the jet stream. This upheaval of marine thermal equilibrium has consequences for the entire planet.
But climate scientists cannot yet predict what will be the intensity this year. John Nielsen-Gammon, its influence is undeniable in Texas: “I think the rains of May would have been impossible without the El Niño effect.”
The economic impact of these disasters elsewhere are already being felt. According to a study published on 2 June by researchers at the University of California Davis , drought will cost $ 1.8 billion (1.6 billion euros) in direct losses to the agricultural sector of the state, which represents 45 billion.