Interview with Christopher Landsea

Q: We are group of students working on the controversy around hurricanes that has been on for almost ten years now, do you agree that there is a controversy?

A: There are differences of opinions yes. 5 years ago the controversy was stronger, with more diversity of opinions and uncertainties, but now it is working towards an agreement. Those who are in the field, working on hurricanes, the perception of those folks, it’s a small group, is almost a general agreement now.

Q: What is your position? Is it different from the one of other scientists?

A: We have seen some warming of the temperatures over the last few decades, the research is conclusive that there is a global warming. But does it mean that hurricanes are changing we don’t surely know. There have been papers published about it, about the expectations on hurricanes changing because of global warming. There are two main findings, one of them is that hurricanes are heat engines so they get warmer, but it’s not a complete answer since it doesn’t say by how much. If it’s really small, how meaningful is that?
When you look at the sensitivity of hurricanes and global warming, all of the studies show a very small sensitivity that compared to a 100 years from now, they may be stronger (only 3%). What it implies in fact is that they might be 1% stronger, which is so small that we can’t measure it.

Q: I had an interview with Kerry Emanuel who told me that the number of storms and hurricanes will indeed not increase, but one must look closer at the number of the strongest ones, which is increasing. What do you think?

A: The numbers of storms will go down substantially, something like 30% fewer storms and hurricanes, so it is completely contradictory. We see no significant increase of strong storms. The best research on this question has been led by the NCDC. While the Atlantic has got busy the last 20 years, the rest of the world decreases! The Atlantic, if you go back further in time, it was just as busy in the late 1920’s to the late 1960’s. So there is a difference of opinion, but my view is that what we observe in the record shows no increase.

Q: What is your opinion on scientists who say that social reasons (such as urbanization of coasts and material damage) are as important as natural causes when studying the impact of hurricanes (I’m thinking of Roger Pielke’s theory here)?

A: If you’re trying to look at trends and time, it’s extremely important to look at how the population has changed and their wealth. Damages are growing up! But you have to consider the changes of capital per head and wealth (which is twice as much now than their parents, four times their grandparents’), so hurricanes damages are still up. It is extremely important that you look carefully at raw numbers.