2. the development of atmospheric models capable of predicting cli- matic variability in order to improve the methods for forecasting climatic anomalies such as droughts or floods which reduce agricultural production, and the development, initially in very broad outline, of planning models which would allow the agricultural industry to make the best use of reliabIe climatic forecasts if and when they appear;

3. development of greater understanding of the significance of climatic fluctuations for crop growth and livestock production;

4. application of ‘risk assessment’ analyses relating the probability of specific climatic fluctuations to economic responses such as the demand for inputs, commodity prices, etc.

BOOK REVIEW

CLIMATE: PRESENT, PAST AND FUTURE, VOL. 2. CLIMATE HISTORY AND THE FUTURE. By H. H. Lamb. London (Methuen & Co. Ltd.), 1977. Pp. 835. €38.00 Volume 1 of this book treated the climate of the present: this volume is mainly

devoted to the climate of the past with just over 50 pages being devoted to future climate. The main section of the book (about 550 pages) describes all possible aspects of

climate back through hundreds of thousands of years. In a middle section of about 100 pages there is an unrivalled collection of tables of climatic data of the most varied kinds followed by two short chapters on future climate. References (arranged by chapters) and subject and geographical indexes occupy the last 120 pages of the book.

The long section on climate of the past is a feast of scholarship ranging over an enormous field covering biological, botanical and magnetic studies, to mention just a few. There is a certain amount of repetition of themes from chapter to chapter which, excusable though it may be, has made the work long and very expensive. It is a pity, though, that the author does not attempt a synthesis of the principal results obtained. Admittedly, in the present state of the subject this would have revealed many incon- sistencies but otherwise there is a very real danger that such a display of scholarship will encourage the view that this mass of information fits consistently into a theory of cfimate.

The seventh chapter entitled ‘Climate since instrument records began’ contains a good account of the relevant studies of this period of 200-300 years, though one would have wished for a little more precision and scepticism in places. As examples I would cite (i) the acceptance on p. 529 that radiation measurements a t the Earth’s surface are sufficiently accurate to show a decline in the intensity of the solar beam in the years preceding 1963, (ii) the suggestion on pp. 53@531 that the parallelism of the global temperature curve with the frequency of westerly winds over the British Isles (the correlation coefficient between 5-year means is only 033!) is evidence of the correctness of the former and (iii) the acceptance of the claim made by Winstanley that the summer monsoon rains in the Sahelian Zone of Africa appear to parallel the frequency of westerly weather types in the British Isles, without mentioning an equally reliable study by Bunting and others claiming that they do not. A strange inconsistency in a book ranging back over thousands of years also appears in this chapter. Anomaly maps of pressure and rainfall for only three years (1970-72) are used to examine the latest trends in circulation and rainfall.

A good chapter on ‘Man-made climatic changes’ is followed by one entitled ‘Ap- proaches to the problem of forecasting’, most of which is, however, devoted to medium range and monthly forecasts and to describing the pressing need for climatic forecasts. There is no critical survey of what scientific basis, if any, there is for making predictions of the future climate. Instead an appendix follows which begs the question, as it were, by listing 24 ‘scientifically based climatic forecasts known to have been issued’. It may well be that the standards of scientific rigour prevailing in the physical sciences are con- stricting and perhaps unattainable in this difficult field but the gratuitous bestowal of the title scientific here is misleading, because several of these forecasts are based on supposed relations between the 80-100 year sunspot cycle and the westerly circulation, or dlrectly with temperature, neither of which can be said to be scientifically established.

I t is indeed a pity that with the unrivalled wealth .of information presented in this volume there is so little critical winnowing. Workers m this field will, however, have reason to be very grateful to the author for gathering in so abundant a harvest, even if they have to do a lot of the winnowing themselves. M. K. MILES

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