Climate models have evolved from a very simple, implicit approach representing surface energy balance and hydrology to complex models that represent many of the key processes through which land surface and climate interact (Pitman, 2003). Model development has tended to focus on GCMs that often perform relatively poorly in tropical regions, or have been developed in temperate areas where there is better input data in terms of climate and environmental parameters, the ecology of the taxa is generally better known, and—as the total number of taxa are relatively few—the system is relatively simple. The time is right to combine expertise from chemical, biological, geoscience, and remote-sensing communities to work with climate modelers to build an integrated framework that is mutually beneficial; indeed, the breadth of knowledge required to develop such a fully integrated approach is intimidating, but can be developed through umbrella organizations such as IGBP-PAGES. Although there are numerous improvements, it is apparent that the current generation of coupled ocean-atmosphere models still have relatively poor simulations of tropical climate change, possibly due to the spatially and temporally variable nature of tropical environments (Ruter et al., 2004). Environmental change is rarely spatially uniform and, therefore, necessitates an even greater wealth of data on present and past environmental states to determine the complexity and patterns behind this. New sites located in key areas, combined with the application of a range of proxies of environmental change, are required to refine our understanding of tropical ecosystem responses to Late Quaternary climatic variations. There also needs to be a realization that the tropics must not be treated with the same assumptions applied to Europe and North America. Accurate representation of tropical areas in Earth system models is a continuing challenge, particularly due to the incredible environmental and ecological diversity.

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