Were the tragic deaths in Alabama linked to climate change? CoyoteBlog makes a pretty convincing case that no, they aren't--and that in fact, tornadoes, which are caused by masses of cold air running into warm air, are probably among the last things we'd expect to increase as the globe warms:
By the way, note the 2nd to last bar, which I believe it the 2008 bar (this chart is really hard to read, but it is the only way I have found the data from the NOAA). In spring of 2008, the media went nuts with a spring spate of tornadoes, saying that the apocalypse was here and this was the ultimate proof of global warming. In particular, ABC ran a story about how the frequency was twice the previous year. Beyond the insanity of drawing long term trends in a noisy system from 2 data points, notice that the previous year was virtually the lowest number in half a century, and despite being twice as high, 2008 turned out to be an average to lower-than-average tornado year. This is what the media does with the climate issue, and why you can trust almost none of it.
We're getting richer, which means that there's more stuff in the way of tornadoes. But it also means that we can afford to build tougher houses, so that fewer people die in them than would in a poorer world.
It's easy to give into the temptation to assume that any change in the weather must be due to global warming. But we've had weather for a long time. Even if we somehow manage to halt global warming, the tornadoes, we will always have with us.