Only once has US seen more billion-dollar weather disasters

Bloomberg

In the year that President Donald Trump pulled out of the Paris accord and downplayed global warming as a security threat, the US received a harsh reminder of the perils of the rise in the planet’s temperature: a destructive rash of hurricanes, fires and floods.
The country recorded 15 weather events costing $1 billion or more each through early October, one short of the record 16 in 2011, according to the federal government’s National Centers for Environmental Information in Asheville, North Carolina. And the tally doesn’t include the recent wildfires in southern California.
In many cases, weather broke records. In others, it was just downright odd, like the February warm spell that sent temperatures to a record 22 Celsius in Burlington, Vermont, and spawned a tornado in Massachusetts.
“When all is said and done, this year is going to be one of the worst years on record for US damages,” said Antonio Busalacchi, president of the University Corporation for Atmospheric Research in Boulder, Colorado.
Among the most devastating events were hurricanes Harvey, Irma and Maria and wildfires in northern California.
The killer storms caused economic losses of more than $210 billion in the US and across the Caribbean, and about
$100 billion in insured damages, according to Mark Bove, a senior research scientist with Munich Reinsurance America in Princeton, New Jersey. The list goes on—ruinous hail in Colorado and Minnesota, tornado outbreaks across the Midwest and South, flooding that damaged a massive dam in California and triggered evacuations downstream. A lake-effect snowband off Lake Erie dumped 34 inches of snow at Pennsylvania’s Erie International Airport on Christmas, quadrupling the previous record from 2002, according to the Weather Channel.
Many of the events can be explained by historical weather patterns. The most calamitous, though, showed signs of a warming climate, including Hurricane
Harvey, which dropped as much as 60 inches of rain as it meandered around the Texas coast after coming ashore as the first of three Category 4 storms to strike the US in 2017.
Warming worsened Harvey’s impacts by boosting moisture in the atmosphere and weakening high-altitude winds that would normally push such a system along, according to Kerry Emanuel, a professor of atmospheric science at the Massachusetts Institute of Technology in Cambridge.
In Texas and elsewhere, “there are certainly indications that these extreme rainfall events are occurring more frequently,” said Greg Carbin, branch chief at the US Weather Prediction Center in College Park, Maryland. Those who are skeptical that climate change is a phenomenon, or that human activity is to blame, contend that dramatic weather this year was happenstance or part of larger, regular meteorological swings. Trump, who has in the past dismissed the concept of man-made climate change as a hoax, announced that the US would leave the Paris climate accord, saying it favours other nations at the expense of American workers.
The overwhelming consensus among scientists is that Earth’s climate is warming and that greenhouse gases are the prime reason. The American Meteorological Society linked changing climate and severe weather in a report that included contributions from researchers at the US National Oceanic and Atmospheric Administration.