Presentation of the influence of deposition uncertainties on acidity critical load exceedance across Wales.

Abstract: Critical loads and exceedances have been used as the basis for negotiation of the Gothenburg Protocol and the National Emissions Ceilings Directive to reduce emissions of sulphur and nitrogen across Europe. Since emissions have already been significantly reduced, the associated cost of further emission reductions is high. In order to define future abatement strategies, policy makers therefore need to understand uncertainties associated with critical load exceedances and interpret them accordingly. Deterministic methods of presenting critical load exceedance, which treat the critical load concept as a set criterion, are well established. Spatially explicit uncertainties in deposition estimates for Wales have recently become available and new ways of presenting information on critical load exceedance are now possible. We explore the utility of partial distributions and inverse cumulative distributions of exceedance data, probability of exceedance and cumulative distribution function by habitat, using Wales as a case study. [Copyright &y& Elsevier]