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The negative impacts of surface ozone (O) on vegetation are determined by external exposure, leaf gas exchange and plant antioxidant defence capacity, all dependent on climate and CO concentrations. In this study the influence of climate change on simulated stomatal O uptake of a generic crop and a generic deciduous tree at ten European sites was investigated, using the LRTAP Mapping Manual stomatal flux model. O concentrations are calculated by a chemistry transport model (MATCH) for three 30-yr time-windows (1961-1990, 2021-2050, 2071-2100), with constant precursor emissions and meteorology from a regional climate model (RCA3). Despite substantially increased modelled future O concentrations in central and southern Europe, the flux-based risk for O damage to vegetation is predicted to remain unchanged or decrease at most sites, mainly as a result of projected reductions in stomatal conductance under rising CO concentrations. Drier conditions in southern Europe are also important for this result. At northern latitudes, the current parameterisation of the stomatal conductance model suggest O uptake to be mainly limited by temperature. This study demonstrates the importance of accounting for the influences by climate and CO on stomatal O uptake, and of developing their representation in models, for risk assessment involving climate change. [ABSTRACT FROM AUTHOR]