The Intersection

On top of that, Emanuel has also won another award--the AMS Louis J. Battan Author's Award--for his book Divine Wind: The History and Science of Hurricanes. It's the very first book that I read when I started researching my own book, Storm World, and I still find myself flipping back through it (and citing it) regularly. It's rare to find a scientist who is both at the top of his field and also adept at explaining his knowledge to the public, but Emanuel has that knack. (Warning: Divine Wind does contain plenty of equations, but they're amply balanced out by history, poetry, and artwork. The book will reward a lay reader even if that lay reader abhors math.)

And finally, last but not least, on Thursday Emanuel is giving the Bernard Haurwitz Lecture on "The Hurricane-Climate Connection," an hour long presentation that itself is a big honor to be asked to deliver, and in a sense counts as a third award. Here's the gist of that presentation:

Hurricanes have long been considered freaks of nature, responding passively to regional climate variability. Although strong empirical relationships have been established between tropical cyclone activity and regional climate signals such as ENSO, the physics behind such relationships are not fully understood, and the subject is not sufficiently advanced that there is even a first-order theory to explain why there are about 90 such events globally each year. In this talk, I will review what current research is revealing about the control of tropical cyclone activity by regional and global climate, and discuss various controversies surrounding the nature of these relationships and how such controversies might be resolved in the next few years. I will also present new evidence that tropical cyclones are far from passive players in global climate, arguing that they collectively supply much of the upper ocean mixing that drives the oceans' thermohaline circulation.

Anyway, let me explain why I find all of this significant. Emanuel, as I've previously stated, can pretty much be thought of as the original hurricane-climate theorist. Going back to 1987, he has been publishing on the idea that hurricanes might be intensified by global warming (PDF), in the context of outlining a theory of the maximum potential intensity that a hurricane can achive given various climatic conditions (i.e., they can get much more intense in the Gulf of Mexico than off the coast of Massachusetts). All of this intellectual history, which is actually quite fascinating, will be treated in my forthcoming book Storm World. For now I'll just add that although I have been able to find some earlier inkings from other authors that there might be a strong hurricane-climate relationship (see e.g. here), there's nothing as systematic or developed as the paper that Emanuel published in '87.

Now fast forward twenty years, to the present. The relationship between hurricanes and global warming has progressed from a relatively obscure side issue in the broader global warming debate into perhaps the most controversial subject in meteorology today. Recent weather and politics alike have had quite a great deal to do with this; I really don't think such a transformation could have happened if not for the devastating 2004 and 2005 Atlantic hurricane seasons.

In this context, that Emanuel is now being awarded the most distinguished honor of the American Meteorological Society seems to me an implicit acknowledgement of how significant and influential his ideas have become, and just how much currency they have at the present moment. Again, all my reporting and interviewing of fellow scientists suggests that Emanuel amply deserves all of these distinctions in a purely scientific sense. But there's no mistaking the subtext: Understanding hurricanes in the context of global climate change seems vastly more important than ever before, and Emanuel has essentially pioneered this area. No wonder he's now being recognized.

As far as hurricanes and global warming go, Emanuel has also staked out a strong position in the current debate, arguing that storms are changing very significantly right now, and in very a scary way. I'll have more on that in my next post....