UNCERTAINTIES IN REACTIVE UPTAKE COEFFICIENTS FOR SOLID STRATOSPHERICPARTICLES .1. SURFACE-CHEMISTRY

Laboratory data for reactions of ClONO2 or HOCl with HCl on nitric aci d trihydrate and sulfuric acid tetrahydrate are compared using a surfa ce reaction model. Data sets where both non-reactive and reactive upta ke were measured reveal that changes in the reactive uptake coefficien ts of ClONO2 and HOCl can be explained completely by the amount of KCI taken up by the hydrates. Large discrepancies are revealed between me asurements from different laboratories which have important consequenc es for calculated ozone destruction (see companion paper II).