From Katrina, an ‘Amazing’ Decade of Climate Research

Hurricane Katrina, along with two blockbuster studies that bookended the disaster, marked the beginning of a decade of rapid growth in a once tiny subfield that has since become one of the most visible in climate science.
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“There’s been an amazing rate of progress in the last 10 years.  I think the next 10 years will be greater,” Gabriel Vecchi, a climate scientist with the National Oceanic and Atmospheric Administration’s Geophysical Fluid Dynamics Laboratory, said.

Setting the Stage
Kerry Emanuel, an atmospheric scientist at MIT, was one of the few scientists who had looked at the question of how hurricane activity might change in a warming climate prior to Katrina.  In a 1987 paper he suggested that warming would lead to more intense, and therefore more potentially destructive, hurricanes (still one of the basic precepts of hurricane-climate research).

In early August 2005, just weeks before Katrina, Emanuel, who had been working on other issues, came back to this idea, with a paper in the journal Nature that took his earlier work a step further.  It suggested that not only would warming lead to more intense and destructive hurricanes in the future, but that this was already happening, helped along by some natural climate variations.  When Katrina struck later that month, interest in his study surged and Emanuel found himself pulled into the cacophonous media coverage.

A separate study by another group followed in mid-September, adding fuel to the fire.  This study, in the journal Science, came to a similar conclusion as Emanuel:  of the hurricanes happening in the global oceans, more were becoming Category 4 and 5 storms than was the case three decades earlier.
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Overall, it is thought that warming will indeed lead to a shift to more intense hurricanes over the course of the 21st century, by anywhere from a few percent to 10 percent, but that overall global hurricane numbers might drop, though by how much is uncertain.

Two of the most robust projections for future hurricanes are that storm surge will be worse, thanks to rising global sea levels, even if hurricanes themselves don’t change, and that storms will bring heavier rains thanks to increased moisture in the atmosphere.

Read more at From Katrina, an ‘Amazing’ Decade of Climate Research