The many faces of climate warming

The release of the fourth assessment report of the Intergovernmental Panel on Climate Change (IPCC) this past February raised the stakes on role of climate warming in our planet’s future. Within the next century our climate is likely to warm by 1.1–6.4C in concert with rising concentrations of greenhouse gases, largely reflecting human influences on radiative forcing (IPCC, 2007). The prospect of climate warming coupled with elevated atmospheric concentrations of carbon dioxide, altered precipitation patterns, and increased nitrogen deposition presents a tangled array of global change drivers and the potential for complex effects on the structure and function of terrestrial ecosystems. Over the past decade, much progress has been made in experimental research and long-term observational studies quantifying the nature and magnitude of climate-warming effects on terrestrial ecosystems and linking them to coupled atmosphere-biosphere processes. Disentangling the direct and indirect effects of warming on ecosystems remains a key conceptual and experimental challenge. To this end, multifactorial experiments and modeling efforts will be key to developing science-based predictions of ecosystem responses to warming (Norby & Luo, 2004). A session organized by Xuhui Zhou and Yiqi Luo (University of Oklahoma, OK, USA) at the 92nd Annual Meeting of the Ecological Society of America in San Jose, CA, USA, in August was aimed at summarizing the findings to date concerning the multiple roles of climate warming in a variety of ecosystems.