What was done
"It has been speculated," in the words of the authors, that "global warming will change the frequency and severity of tropical and extratropical storms."  Hence, to determine if there is any validity to this "speculation," they utilized ten very long records of storm surges derived from hourly tide gauge measurements along the east coast of the United States to calculate indexes of count, duration and integrated intensity of such storms that provide objective, quantitative and comprehensive measures of historical storm activities in this region.

What was learned
The authors concluded that their analysis "does not show any discernible long-term secular trend in storm activity during the twentieth century," which they further conclude "suggests a lack of response of storminess to minor global warming along the U.S. Atlantic coast during the last 100 yr."

What it means
Speculation, even sophisticated climate model-derived speculation, is, well, just speculation.  It may incite massive political activity the world over; but it has absolutely no clout when it comes to influencing the world of nature, i.e., the real world. Perhaps there is a message there for us.