Accurate and reliable predictions and an understanding of future changes in the stratosphere are major aspects of the subject of climate change. Simulating the interaction between chemistry and climate is of particular importance, because continued increases in greenhouse gases and a slow decrease in halogen loading are expected. These both influence the abundance of stratospheric ozone. In recent years a number of coupled chemistry–climate models (CCMs) with different levels of complexity have been developed. They produce a wide range of results concerning the timing and extent of ozone-layer recovery. Interest in reducing this range has created a need to address how the main dynamical, chemical, and physical processes that determine the long-term behavior of ozone are represented in the models and to validate these model processes through comparisons with observations and other models. A set of core validation processes structured around four major topics (transport, dynamics, radiation, and stratospheric chemistry and microphysics) has been developed. Each process is associated with one or more model diagnostics and with relevant datasets that can be used for validation. This approach provides a coherent framework for validating CCMs and can be used as a basis for future assessments. Similar efforts may benefit other modeling communities with a focus on earth science research as their models increase in complexity.
DLR Institute of Atmospheric Physics, Oberpfaffenhofen, Germany
European Ozone Research Coordinating Unit, Cambridge, United Kingdom
Alfred Wegener Institute for Polar and Marine Research, Potsdam, Germany
Department of Physics, University of Toronto, Canada
NOAA Aeronomy Laboratory, Boulder, Colorado
European Commission, Brussels, Belgium
NOAA GFDL, Princeton, New Jersey
University of Leeds, School of Earth and Environment, Leeds, United Kingdom
DLR Institute of Atmospheric Physics, Oberpfaffenhofen, Germany
University of Reading, Department of Meteorology, Reading, United Kingdom
NCAR, Boulder, Colorado
University of Cambridge, Centre for Atmospheric Science, Department of Geography, Cambridge, United Kingdom
National Institute for Environmental Studies, Tsukuba, Japan
NASA Goddard Space Flight Center, Greenbelt, Maryland
Earth System Science Department, University of California at Irvine, Irvine, California
University of Cambridge, Centre for Atmospheric Science, Chemistry Department, Cambridge, United Kingdom
Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California
Program for Climate Model Diagnosis and Intercomparison, Lawrence Livermore National Laboratory, Livermore, California
Johns Hopkins University, Baltimore, Maryland
