For a long time, the scientists have been telling us global warming increases the temperature of the top layer in the ocean, and that causes the average hurricane to become a lot stronger. So, the fact that the ocean temperatures did go up because of global warming, because of man-made global warming, starting around in the '70s, and then we had a string of unusually strong hurricanes outside the boundaries of this multi-decadal cycle that is a real factor; there are scientists who point that out, and they're right, but we're exceeding those boundaries now.