For more than a decade, the question of how global warming is affecting the scariest storms on the planet -- hurricanes -- has been shot through with uncertainty. The chief reason is technological: In many parts of the world, storm strengths are estimated solely based on satellite images. Technologies and techniques for doing this have improved over time, meaning that there is always a problem with claiming that today's storms are stronger than yesterday's. After all, they might just be better observed.
That's why, despite expectations that global warming will make hurricanes stronger -- as well as massive societal consequences if more powerful storms are slamming coastlines -- scientific authorities like the United Nation's Intergovernmental Panel on Climate Change have demurred on the hurricane/climate question. Most recently, the IPCC earlier this year said it had "low confidence" that global warming is worsening hurricanes.