The changing climate: Using modeling to predict potential effects on horticultural crops

The main aim of this manuscript is to provide some fundamental concepts related to climate and to its inherent variability, which might be considered an essential tool for a better judgment of the large amounts of information currently available regarding this topic. This is particularly pertinent for agricultural research, as agronomic systems, including horticultural crops, tend to be largely regulated by climate and by atmospheric parameters. Some elementary concepts on the nature of the climate system are first presented. Its components and coupling processes are succinctly described, giving particular emphasis to the spatial and temporal time scales relevant for agro-systems research. Both internal and forced climate variability are discussed from a physically-based perspective with a special focus on the anthropogenic forcing of the climate system. The discussion of these topics is followed by some essential ideas on atmospheric modeling. The need for the development of downscaling strategies is also underlined. A categorization of the different climate system models and their application to agro-system research are thus discussed. The role of greenhouse gases in the radiation and energetic budget of the Earth's system are examined. In this respect, some relevant results of the last IPCC report concerning human-driven forcing mechanisms are also presented. Lastly, the likely impacts of a changing climate on several agronomic sectors are briefly covered.