To the ever-growing list of ways humanity seems to have altered the earth, add another candidate: Air pollution may have had a major soothing influence on storm cycles in the North Atlantic.
That is the finding of a paper published this week, suggesting that industrial pollution from North America and Europe through much of the 20th century may have altered clouds in ways that cooled the ocean surface. That, in turn, may have suppressed storms, and particularly major hurricanes, below the level that would have existed in a purely natural environment.
If the authors are right, the upturn in storms over the last couple of decades may be no accident. It could, instead, be at least partly a consequence of the clean air acts that have reduced pollution around the North Atlantic basin, thus returning the storm cycles to their more natural state.