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Physical principles of micro-meteorological measurements
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The text includes some 400 references, which will be of value to research workers and students new to the subject. However, they should be warned that even such a list can only be a selection, and that inevitably some important papers may have been omitted. Two examples come to mind: the work by D. L. Curtis (J. Appl. Ecol., 5: 215--226) on the relationship between date of flowering of sorghum and the end of the rains in Nigeria, and the references quoted by A. H. Kassam and J. M. Kowal (Agric. Meteorol., 15: 333--342) on the determinations of crop-water use by sorghum, millet, cotton, maize and groundnuts at Samaru, Northern Nigeria. An extensive and complicated subject has been dealt with in a relatively short space and, as a result, it is sometimes necessary to read the text carefully to grasp the main points and to follow the underlying logic. Despite these criticisms, Dr. Jackson's book is a useful and convenient summary of the characteristics of rainfall and the relationships between agriculture and soil moisture in the tropics. It will be of considerable value for m a n y university courses in agriculture, agricultural meteorology and tropical geography. It can usefully be read by all concerned with tropical development for whom an appreciation of the influence of weather and climate on tropical agriculture and land use is essential. It offers a very necessary awareness of the problems, even if it does not pretend to provide all the answers. M. D. DENNETT (Reading)
Physical Principles of Micro-Meteorological Measurements. P. Schwerdtfeger. Elsevier, Amsterdam, 1976, 113 pp., US $24.95.
Micro-meteorology is an experimental science but most text-book accounts of the subject from ' S u t t o n ' onwards seem more concerned with principles than with practices. Professor Schwerdtfeger has tried to redress the balance by combining some of the elements of micro-meteorological theory with a series of experiments designed both for the laboratory and for the field. The topics which he covers include the measurement of temperature, vapour pressure, wind, radiation, and soil heat flux. Some of the instruments can be made in the laboratory; others are standard commercial products. An attractive feature of the book is the way in which basic principles of heat transfer are developed to explain the behaviour of thermometers and psychrometers but the theory of radiometers is dealt with more superficially. The theory of soil heat conduction gets full treatment and the final chapter contains some original material on the construction of electrical analogues
164
of thickening ice sheets and of the heat balance of the atmospheric boundary layer. Most of the material is well set out and adequately illustrated but close inspection of the text reveals a number of defects. Suggestions for the construction of apparatus are very brief. Research students might find them useful b u t inexperienced undergraduates will be baffled, for example, by the 10-line description of a plated thermopile, unaccompanied by a diagram. Another disappointing omission is the almost complete absence of real measurements, either in tabular or in graphical form, which would give students confidence that they were working on the right lines. Even more surprising is the omission of references within the text. There is a general bibliography to conclude the book, b u t it would have been more useful with references to standard texts on the measurement of temperature, humidity, and air flow. There are a number of errors. The derivation of the psychrometer formula (p. 51) is peculiar to this text. It appears to be fallacious and leads directly to an erroneous definition of the Bowen Ratio (p. 54). The thermal inertia of wet-bulb sensors is rarely significantly greater than that of corresponding dry-bulbs -- it is usually smaller. But perhaps all these criticisms are irrelevant if, as seems likely, the price of the b o o k precludes its use by students. At nearly $ 25 for 113 pages (including the index), this is probably the most expensive meteorological monograph on the market. Physical Principles of Micro-meteorological Methods is the sixth in Elsevier's series of 'Developments in Atmospheric Science'. Teachers and research workers must hope that if cost significantly inhibits its sale, the publishers will review their marketing policy before introducing further titles in the series. J. L. MONTEITH (Loughborough)
The text includes some 400 references, which will be of value to research workers and students new to the subject. However, they should be warned that even such a list can only be a selection, and that inevitably some important papers may have been omitted. Two examples come to mind: the work by D. L. Curtis (J. Appl. Ecol., 5: 215--226) on the relationship between date of flowering of sorghum and the end of the rains in Nigeria, and the references quoted by A. H. Kassam and J. M. Kowal (Agric. Meteorol., 15: 333--342) on the determinations of crop-water use by sorghum, millet, cotton, maize and groundnuts at Samaru, Northern Nigeria. An extensive and complicated subject has been dealt with in a relatively short space and, as a result, it is sometimes necessary to read the text carefully to grasp the main points and to follow the underlying logic. Despite these criticisms, Dr. Jackson's book is a useful and convenient summary of the characteristics of rainfall and the relationships between agriculture and soil moisture in the tropics. It will be of considerable value for m a n y university courses in agriculture, agricultural meteorology and tropical geography. It can usefully be read by all concerned with tropical development for whom an appreciation of the influence of weather and climate on tropical agriculture and land use is essential. It offers a very necessary awareness of the problems, even if it does not pretend to provide all the answers. M. D. DENNETT (Reading)
Physical Principles of Micro-Meteorological Measurements. P. Schwerdtfeger. Elsevier, Amsterdam, 1976, 113 pp., US $24.95.
Micro-meteorology is an experimental science but most text-book accounts of the subject from ' S u t t o n ' onwards seem more concerned with principles than with practices. Professor Schwerdtfeger has tried to redress the balance by combining some of the elements of micro-meteorological theory with a series of experiments designed both for the laboratory and for the field. The topics which he covers include the measurement of temperature, vapour pressure, wind, radiation, and soil heat flux. Some of the instruments can be made in the laboratory; others are standard commercial products. An attractive feature of the book is the way in which basic principles of heat transfer are developed to explain the behaviour of thermometers and psychrometers but the theory of radiometers is dealt with more superficially. The theory of soil heat conduction gets full treatment and the final chapter contains some original material on the construction of electrical analogues
164
of thickening ice sheets and of the heat balance of the atmospheric boundary layer. Most of the material is well set out and adequately illustrated but close inspection of the text reveals a number of defects. Suggestions for the construction of apparatus are very brief. Research students might find them useful b u t inexperienced undergraduates will be baffled, for example, by the 10-line description of a plated thermopile, unaccompanied by a diagram. Another disappointing omission is the almost complete absence of real measurements, either in tabular or in graphical form, which would give students confidence that they were working on the right lines. Even more surprising is the omission of references within the text. There is a general bibliography to conclude the book, b u t it would have been more useful with references to standard texts on the measurement of temperature, humidity, and air flow. There are a number of errors. The derivation of the psychrometer formula (p. 51) is peculiar to this text. It appears to be fallacious and leads directly to an erroneous definition of the Bowen Ratio (p. 54). The thermal inertia of wet-bulb sensors is rarely significantly greater than that of corresponding dry-bulbs -- it is usually smaller. But perhaps all these criticisms are irrelevant if, as seems likely, the price of the b o o k precludes its use by students. At nearly $ 25 for 113 pages (including the index), this is probably the most expensive meteorological monograph on the market. Physical Principles of Micro-meteorological Methods is the sixth in Elsevier's series of 'Developments in Atmospheric Science'. Teachers and research workers must hope that if cost significantly inhibits its sale, the publishers will review their marketing policy before introducing further titles in the series. J. L. MONTEITH (Loughborough)