Additional info from The Climate Reality Project
Scientists have been warning since at least the late 1980s that higher sea surface temperatures can increase the destructive power of hurricanes. Hurricanes are fueled by warm, moist air that evaporates from the surface of the ocean, and more water evaporates from the surface when the temperature is high. The global average sea surface temperature has increased since 1860, so it's reasonable to expect that hurricanes would also become more destructive.
But high sea surface temperatures aren’t the only ingredient for a “successful” hurricane. For instance, powerful hurricanes can churn up cold water from deeper layers of the ocean, lowering the sea surface temperature and reducing the chance that fledgling storms nearby will reach their full potential.
The full body of available evidence suggests the number of hurricanes may stay the same or decrease slightly. But the hurricanes that do form may get stronger and wetter by the end of the century, with a 2-11% increase in hurricane intensity and 20% more rainfall, on average.
These percentages may sound small, but consider that most of the damage and deaths from hurricanes come from flooding caused by rain or storm surges. (A storm surge is a wall of ocean water that gets pushed inland by a hurricane.) Hurricane Katrina, for instance, was the third deadliest and most expensive hurricane ever in the U.S. It also had the highest surge on record in the country. And because sea levels are rising as the world gets warmer, there’s a higher risk of coastal flooding during even a minor hurricane. In New York City alone, so-called “1 in 100 year” coastal floods could happen every 3-20 years by the end of the century because of sea level rise and the risk of more intense hurricanes.
As the residents of New Orleans or Pamlico Country, North Carolina can tell you, it only takes one intense hurricane to cause years of grief. The best evidence suggests hurricanes will get more intense as the world warms. And the more global warming pollution we put into the atmosphere, the worse things will get.