Michael E Mann writes: What can we say about the role of climate change in the unprecedented disaster that is unfolding in Houston with Hurricane #Harvey?

There are certain climate change-related factors that we can, with great confidence, say worsened the flooding.

Sea level rise attributable to climate change (some is due to coastal subsidence due to human disturbance e.g. oil drilling) is more than half a foot over the past few decades (see http://www.insurancejournal.com/…/sou…/2017/05/31/452704.htm for a decent discussion).

That means that the storm surge was a half foot higher than it would have been just decades ago, meaning far more flooding and destruction. [Continue reading…]

The Washington Post reports: The worst fears of flooding have been realized with Harvey. Close to three feet of rain has already fallen in Southeast Texas, and there’s still more to come. It’s the most extreme rainfall the region has ever witnessed.

On Sunday evening, brand new bands of torrential rain were forming southwest of Houston and appeared on track to strike the city overnight. Rainfall rates will almost certainly exceed three inches per hour over the already-submerged city. That threat prompted the National Weather Service to reissue the flash flood emergency — the strongest flood warning it can issue — in effect through around 1 a.m. Central Time.

Two-day rainfall totals have reached or exceeded 20 inches across the entire Houston metro area. Some locations are approaching 30 inches. The swift inundation of water has turned rivers, bayous and streams into lakes — including those that run through the city of Houston itself.

“Catastrophic flooding in the Houston metropolitan area is expected to worsen,” the National Weather Service said Sunday. It added: “This event is unprecedented and all impacts are unknown and beyond anything experienced.” [Continue reading…]