Content area
Full text
GLOBAL WARMING: MYTH OR REALITY? Marcel Leroux, 2005, 509 pp., $129.00, hardbound, Spnnger-Verlag, ISBN 3-540-23909-X
The cover and size of this hook hint that it may serve as a bible to those who question that climate change is caused by humans. That would be correct for a part-but only a part-of the book, which is really two books in one.
Marcel Leroux, professor emeritus of climatology in Lyon, France, has long advanced an alternative hypothesis for the general circulation of the atmosphere, one that gives a central role to "Mobile Polar Highs" (MPH), or polar air masses in motion. One purpose of the book is to construct a climatology based on MPHs and explore what phenomena the new scheme can explain. The other purpose is to assert that the greenhouse effect in the atmosphere does not influence climate change, and thus that humans have no role in contemporary climate changes, which the author asserts are natural.
Beyond these two scientific purposes, the book also criticizes the news media and some scientists for feeding the public the most sensationalistic scenarios of the future climates that can be constructed. He is unfogiving with those who feed that journalistic hunger. In a more collegial spirit, he urges the discipline to drop its focus on greenhouse-gas warming, and spend less time on modeling and more time on developing concepts that may unravel mysteries in climate dynamics. This review will focus only on the two scientific themes.
Leroux wants to construct a theory of general circulation of the atmosphere that is driven by the flow in low levels. He believes that Mobile Polar Highs are a useful concept that can explain the way the weather works. They originate as shallow anticyclones formed by cold air masses that move away from the poles under the influence of gravity, like a density current. The MPH advances through the middle latitudes along a preferred trajectory, pushing aside warmer, moister air, and even reaches the subtropics to sustain the trade-wind belts. While the MPH exists entirely in low levels, the return flow can and does ascend to middle and high levels in the low-pressure zones between neighboring MPHs, where troughs, fronts, and cyclones tend to form. This relatively warm and moist poleward flow, where...