Simulating Past and Forecasting Future Climates
- 1 January 1993
- journal article
- research article
- Published by Cambridge University Press (CUP) in Environmental Conservation
- Vol. 20 (4) , 339-346
- https://doi.org/10.1017/s0376892900023547
Abstract
Climatic change is not a new phenomenon, nor is it random, as most of the variation can be explained in terms of variations in the sunlight reaching the surface of the Earth. The solar energy reaching the surface is modified by the aerosols in the atmosphere, however, and that means primarily aerosols of volcanic origin.The climatic history of the Earth is divided up into episodes with abrupt beginnings and ends. Rapid changes from one climatic state to another are normal. The fluctuations within this century do not appear to be unusual in any respect.To the Author's knowledge there is no evidence that past climatic changes, including those of the last decades, are related to changes in carbon dioxide in the atmosphere—except perhaps for warmer nights in the North American mid-west. It is not possible to simulate past climates using carbon dioxide content as the main variable, but it is possible to do so using calculated solar radiation as modified by volcanic aerosols. This strongly suggests that forecasts of the climatic future based on carbon dioxide increases are suspect.Computerized models of the climate that can simulate decadal and century-long variations of climate as well as variations on the millennium scale, suggest that the climate will not warm dramatically in the next fifty years, but will, rather soon after that, begin a rather rapid change towards the next glacial climate.Changes in our global array of cultures, sufficient to affect the global climate in a way which we perceive as beneficial, probably are not possible within centuries without massive physical conflict. There are both winners and losers when the climate changes in a non-uniform pattern, as it always does. It is a well-known fact that a global change of 0.5°C in mean temperature, such as has happened in recent years, might produce some regions of 10°C change in either direction and some regions with no change at all, and additionally an array of rainfall changes of various magnitudes. Russians would welcome warming of their climate!The problems with attempting to modify the global climate in a particular direction are enormous and would be incredibly costly. This is compounded by our not knowing what the climate would do without intervention. Only one thing is truly clear, and it is that the present knowledge of the climatic effect of changing carbon dioxide content of the atmosphere is totally inadequate as a basis for initiating any global attempt to change the climate.The indicated action would appear to be to engage in some high-quality climatic research based on sound science before taking global risks greater than those that might arise from the putative ‘global warming’.Keywords
This publication has 17 references indexed in Scilit:
- A macrophysical model of the holocene intertropical convergence and jetstream positions and rainfall for the Saharan regionArchiv für Meteorologie, Geophysik und Bioklimatologie Serie A, 1992
- Modelling the NW India monsoon for the last 40 000 yearsClimate Dynamics, 1989
- Global surface air temperatures: Update through 1987Geophysical Research Letters, 1988
- Worldwide marine temperature fluctuations 1856–1981Nature, 1984
- Late Glacial and Holocene climatic history of the Sahara Desert derived from a statistical assay of 14C datesPalaeogeography, Palaeoclimatology, Palaeoecology, 1974
- Dating Climatic Episodes of the HoloceneQuaternary Research, 1974
- Late- and Postglacial Climatic Change in the Northern Midwest, USA: Quantitative Estimates Derived from Fossil Pollen Spectra by Multivariate Statistical AnalysisQuaternary Research, 1972
- An Empirical Formulation of an ITD Rainfall Model for the Tropics: A Case Study of NigeriaJournal of Applied Meteorology, 1971
- GENERAL CIRCULATION EXPERIMENTS WITH THE PRIMITIVE EQUATIONSMonthly Weather Review, 1963
- The Influence of Great Epochs of Limestone Formation upon the Constitution of the AtmosphereThe Journal of Geology, 1898