I guess that since their bluff was called on hurricanes, waves are the next in line.
As an East Coast surfer, my n = 1 study tells me that we had better hurricane swells about 10-20 years ago. 1998, an El Nino year, we had some good waves from the tropics. I think 2005 and 2010 were also good years.
My issue with all of these theoretical studies and the news that covers them is that there is never discussion of the uncertainties. What is man’s ability to accurately measure global wave activity? What about prior to the 70s? What are the error bars?