Global Cooling?

Science  06 Aug 1976:
Vol. 193, Issue 4252, pp. 447-453
DOI: 10.1126/science.193.4252.447


The world's inhabitants, including Scientists, live primarily in the Northern Hemisphere. It is quite natural to be concerned about events that occur close to home and neglect faraway events. Hence, it is not surprising that so little attention has been given to the Southern Hemisphere. Evidence for global cooling has been based, in large part, on a severe cooling trend at high northern latitudes. This article points out that the Northern Hemisphere cooling trend appears to be out of phase with a warming trend at high latitudes in the Southern Hemisphere. The data are scanty. We cannot be sure that these temperature fluctuations are be not the result of natural causes. How it seems most likely that human activity has already significantly perturbed the atmospheric weather system. The effect of particulate matter pollution should be most severe in the highly populated and industrialized Northern Hemisphere. Because of the rapid diffusion of CO2 molecules within the atmosphere, both hemispheres will be subject to warming due to the atmospheric (greenhouse) effect as the CO2 content of the atmosphere builds up from the combustion of fossil fuels. Because of the differential effects of the two major sources of atmospheric pollution, the CO2 greenhouse effect warming trend should first become evident in the Southern Hemisphere. The socioeconomic and political consequences of climate change are profound. We need an early warning system such as would be provided by a more intensive international world weather watch, particularly at high northern and southern latitudes.