Crop response to climate: ecophysical models

Authors: White, Jeffrey; HOOGENBOOM, GERRIT - U OF GA, GRIFFIN, GA

Submitted to: Climate Change and Food Security: Adapting Agriculture to a Warmer World
Publication Type: Book / Chapter
Publication Acceptance Date: 3/1/2009
Publication Date: 12/1/2009
Citation: White, J.W., Hoogenboom, G., 2009. Crop response to climate: ecophysical models, pp. 59-84. In: Lobell, D. and Burke, M. (eds), Climate Change and Food Security: Adapting Agriculture to a Warmer World Series: Advances in Global Change Research, Springer, New York.

Interpretive Summary: To predict the possible impacts of global warming and increased CO2 on agriculture, scientists use computer-based models that simulate the growth of crop plants. The models, variously known as “ecophysiological models,” “crop models” or “simulation models”, were the dominant tools used in the Intergovernmental Panel on Climate Change (IPCC) Third and Fourth Assessment Reports. The models are also widely used elsewhere in climate change research. The models attempt to represent the best-available knowledge on plant physiology, agronomy, soil science and meteorology in order to predict how a plant will grow under specific environmental conditions. This book chapter is directed toward university students with a basic knowledge of biology who wish to understand how crop models work and more specifically, how characteristics of the models affect predictions of climate change impact. The chapter reviews the basic features of crop models with emphasis on physiological responses to temperature and CO2. Sections deal with development, growth, and responses to environment and crop management. The chapter also explains how models are used to predict potential impacts of climate change, including options for adaptation. A closing section mentions some of the main issues affecting the reliability of model-based predictions. These include the need for accurate inputs, the challenges of improving the underlying physiological knowledge, and the need to improve representations of genetic variation that likely will affect adaptation to climate change. This chapter should help non-specialists make more informed decisions about climate change in agriculture and encourage students to pursue research in the area of crop modeling and climate change.

Technical Abstract: Ecophysiological models were the dominant tools used to estimate the potential impact of climate change in agroecosystems in the Third and Fourth Assessment Reports of the IPCC and are widely used elsewhere in climate change research. These models, also known as “crop models” or “simulation models”, encapsulate the best-available knowledge on plant physiology, agronomy, soil science and agrometeorology in order to predict how a plant will grow under specific environmental conditions. This chapter reviews the basic features of crop models with emphasis on physiological responses to temperature and CO2 due to their importance in climate change. Thus, sections deal with development, growth, and responses to environment and crop management. The chapter also explains how models are used to predict potential impacts of climate change, including options for adaptation. A closing section mentions some of the main issues affecting model-based projections of impact. These include the need for accurate inputs, the challenges of improving the underlying physiological knowledge, and the need to improve representations of genetic variation that likely will affect adaptation to climate change.