VIEW ARTICLE

Letter to the Editor

Global Warming and Nonlinear Growth: How Important are Changes in Average Temperature? H. Scherm and A. H. C. van Bruggen. Department of Plant Pathology, University of California, Davis 95616. Phytopathology 84:1380-1384. Accepted for publication 12 September 1994. Copyright 1994 The American Phytopathological Society. doi:10.1094/Phyto-84-1380.

Increasing concentrations of greenhouse gases, particularly CO(2), in the lower atmosphere have led to concern about global changes in temperature and precipitation patterns. It has been estimated that mean surface air temperature will rise at a rate of ~0.3–0.4 C per decade because of the increased greenhouse effect (2,10). These projections are based on outputs from General Circulation Models (GCMs). GCMs are coupled ocean-atmosphere models that simulate the transfer of heat, mass, and momentum in the lower atmosphere. They are reliable tools for simulating climate on large temporal and spatial scales, but they have two important drawbacks that may limit their usefulness for estimating the potential impact of global warming on biological processes.