Frequency of two-day heavy rain events, 1900-2015, compared with the 1901-1960 average. Graphic: CNN / Kunkel, et al., 2013

By Wayne Drash
15 September 2017
(CNN) – The right time to talk climate change is now.
It might seem premature when people in the Caribbean, Florida, and Texas are still mucking out their flooded homes.
And no, changes in our planet’s atmosphere did not cause Hurricanes Harvey or Irma. But the consensus among scientists is that the effects of climate change, such as rising sea levels and warmer oceans, made those storms far more destructive than they would have been in previous decades.”The short version is, climate change makes these very bad storms worse,” said Sean Sublette, a meteorologist with Climate Central, a nonprofit group that studies climate change. “It’s not the approximate cause of the storm, but it makes these bad storms worse. And in the case of a really bad storm, climate change can make it totally disastrous or catastrophic.”The data on how our warming planet specifically impacted Harvey and Irma won’t be known for quite some time. It can take months and even years to collect and analyze that information.But the science is this: Hurricanes thrive over warm water and strengthen in intensity; oceans have warmed on an average 1 to 3 degrees Fahrenheit over the past century, and sea levels have risen about 7 inches during that time. Throw in compound flooding — the combination of rising sea levels from global warming, storm surge and extreme rainfall — and you have the perfect mix for record flooding.We saw this in greater Houston from Harvey and along the 240-mile stretch of the Atlantic coast from Jacksonville, Florida, to Charleston, South Carolina as a result of Irma’s storm surge and heavy rains. [more]

Yes, climate change made Harvey and Irma worse