Hurricane season is here. An extreme weather expert explains what's in store.

I understand that since 1995 we've seen stronger Atlantic hurricanes. Why is that?

That's a good question, and that's somewhat debated in my field. There's one thing there's little question about: the waters of the tropical Atlantic are warmer now than they were in the 1980s. That is maybe a little bit because of the phenomenon of global warming, but a great part of it is likely due to the fact that there are fewer sulfate aerosols in the atmosphere now than there were in the 1980s.

One side effect of burning fossil fuels and burning land areas to clear them is that it puts particles in the atmosphere that have the effect of reflecting sunlight and making the planet's surface cooler. We had a lot of those around the '80s, and they started to decline in the late 1980s because of the Clean Air Act and variations of that in Europe and elsewhere. We cleaned up our act, which was a good thing, because those aerosols are very bad for our health — but a sad side effect of that is that without that cooling, the oceans started to warm up. That brought back the hurricanes.