Windswept: The Story of Wind and Weather
by Marq De Villiers 388 pages, ISBN: 0771026447
Post Your Opinion | | Measuring Wind by Morley Thomas
Marq de Villiers has written a delightful book on wind and weather that is both informative and fascinating. The author has previously published successful books on exploration, history, politics, water, and travel, and in this book he demonstrates that he can persuasively write on weather and climate as well. Any meteorologist aspiring to write on the subject for the general public would be wise to acquire and closely read Windswept since the author demonstrates that the wonders of wind and weather can be explained without the use of mathematical equations and professional jargon. This book is hardly a textbook, but I recommend it to anyone interested in forecasts and weather in general.
Throughout the text de Villiers effectively introduces all of the chapters with recollections from relevant personal experience or from memorable weather events he has read about. Clearly, hurricanes, tornadoes, and other great windstorms have fascinated him throughout his life, and, perhaps because of this, he has used instalments of "Ivan's story" at the beginning of each chapter to string them all together. Ivan, a complex hurricane of August-September 2004, inflicted extensive property damage and loss of life in the Caribbean and the United States before moving out and weakening over the Atlantic Ocean and then causing very limited damage to de Villiers's property in Nova Scotia. Ivan's story is good reading but it would have been better if it had been presented without breaks in a single chapter. I could not see any relationship between the bits of Ivan's story and the content of each chapter so I skipped these 'introductions', returning to them only after having finished the chapters. But, this is a small criticism of a very good book.
Beginning with ancient beliefs and the local names given to specific winds in various parts of the world, the author recounts how man's knowledge of the composition of air ("the stuff that makes wind") grew over the period of recorded history until reaching the more modern realisation that there are identifiable layers in the atmosphere. He then explains how Anaximander, a philosopher in the sixth century BCE, appears to have been the one who first gave us a quasiscientific definition of wind, and how the Greeks identified the cardinal wind directions and built the precisely oriented eight-sided Tower of the Winds in Athens. Of course, sailors have always used the wind, and by the time of Columbus they understood the warning signs of bad weather although it would be another century before both the wind directions and some indication of their speeds were routinely recorded in meteorological logs and daybooks.
A theory of storms developed more slowly than practical knowledge about them. It was not until the early decades of the 19th century that their true cyclonic nature was understood by men who were called "scientists". This new designation replaced the earlier term "natural philosophers". One of these scientists was an American naval officer, Matthew Fontaine Maury, who published his research on meteorology and oceanography after extended voyages around the world. He is best known in meteorological history for developing a system that allowed sea captains to record meteorological and oceanographic data. The system was adopted internationally at a congress in Brussels in 1853. This was followed by another international meeting of scientists in Vienna in 1871, where methods of meteorological observation and the definitions of terms were adopted, leading to the establishment of an organisation that is today known as the World Meteorological Organisation.
Also during the mid-1800s, Sir Francis Beaufort, who was to become a rear admiral in the Royal Navy, developed a scale for estimating the force of the wind by observing its effect on ships' sails. The Beaufort number increased from 0 in a calm to 12 in a hurricane; its use was made mandatory in the Royal Navy by 1838 and international use soon followed. Eventually the scale was adapted for land use with reference to the wind effects on trees, chimneys, and buildings. The Beaufort scale is still the basis for reporting wind in meteorology, but the equivalent values used in weather reports are expressed in knots, imperial units, or metric units. The author mentions the gale warning service introduced in Britain in the 1850s, and he might have told readers that the national meteorological services of both the United States and Canada were first federally established in the 1870s to issue storm warnings for the Great Lakes and Atlantic Coast.
Weather analysts and forecasters require representative meteorological elements from reporting stations to construct a weather map. Amongst the surface elements the wind measurement is usually the most problematic. Ideally, wind should be measured at ten meters above a flat surface at a distance from any obstructions such as trees or buildings, but until remote sensing became available these conditions were difficult to meet at airports and other observing stations. Further, pedestrians on downtown urban streets rarely experience a representative wind since large buildings sometimes give shelter and other times create a "canyon effect". Now, when large structures are planned, building codes call for the study of the effect of wind forces on models in wind tunnels to produce design values.
Only in the last century was meteorological theory so developed that forecasters required upper air winds in their weather map analysis. At first only pilot balloon observations, made by watching and recording the altitude and azimuth of a rising balloon, were available. But after only a few kilometres the observer would lose sight of the balloon, and, of course, observations were not available on cloudy days. However, in the 1930s, radiosondes, instruments carried aloft by balloons, were invented to transmit temperature, pressure, and humidity data back to earth as they rise through the atmospheric layers to nearly thirty kilometres. Using radar, the position of the balloon is known at all times, and so the wind speed and direction can also be continuously determined along with the other elements.
De Villiers is particularly good at reminding us of the effects of wind on nature, such as the distribution of plant seeds and harmful fungi, as well as on our economic and social lives by causing the movement of atmospheric pollution. He eplains how wind has, over the centuries, powered the development of maritime and air transport. And he examines wind as a source of energy and notes the attention given to it in today's climate-change debate as a partial substitute for the use of coal, which would slow the increase of carbon dioxide in the atmosphere and global warming. The author does not spell out his convictions, but it is evident to me that he thinks the need for wind power will soon become widely recognised.
De Villiers has suffered only a little from hurricanes but they have certainly sparked his interest in wind and weather. He has written one of the best books on the subject that I have ever read. ò
Morley Thomas is a retired meteorologist and former director general of the Canadian Climate Centre. ECW Press has published three of his books on the history of meteorology in Canada.
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