By Elizabeth Landau, CNN
Yes, climate change is happening. But it's hard to say that the tornado that ripped through Moore, Oklahoma - or any given tornado, for that matter - was influenced by climate change.
Scientific research has not made a clear connection between tornadoes and climate change, said J. Marshall Shepherd, climate change expert and professor at the University of Georgia.
There is currently a much better understanding of how climate change increases the risks of droughts, heat waves and precipitation, he said. There are also indications that changing patterns may influence the intensity of hurricanes. But as far as tornadoes: There's just not a lot of information.