Reconciliation of essential process parameters for an enhanced predictability of Arctic stratospheric ozone loss and its climate interactions (RECONCILE): Activities and results
- ISSN: 16807316
- DOI: 10.5194/acp-13-9233-2013
The international research project RECONCILE has addressed central\nquestions regarding polar ozone depletion, with the objective to\nquantify some of the most relevant yet still uncertain physical and\nchemical processes and thereby improve prognostic modelling capabilities\nto realistically predict the response of the ozone layer to climate\nchange. This overview paper outlines the scope and the general approach\nof RECONCILE, and it provides a summary of observations and modelling in\n2010 and 2011 that have generated an in many respects unprecedented\ndataset to study processes in the Arctic winter stratosphere.\nPrincipally, it summarises important outcomes of RECONCILE including (i)\nbetter constraints and enhanced consistency on the set of parameters\ngoverning catalytic ozone destruction cycles, (ii) a better\nunderstanding of the role of cold binary aerosols in heterogeneous\nchlorine activation, (iii) an improved scheme of polar stratospheric\ncloud (PSC) processes that includes heterogeneous nucleation of nitric\nacid trihydrate (NAT) and ice on non-volatile background aerosol leading\nto better model parameterisations with respect to denitrification, and\n(iv) long transient simulations with a chemistryclimate model (CCM)\nupdated based on the results of RECONCILE that better reproduce past\nozone trends in Antarctica and are deemed to produce more reliable\npredictions of future ozone trends. The process studies and the global\nsimulations conducted in RECONCILE show that in the Arctic, ozone\ndepletion uncertainties in the chemical and microphysical processes are\nnow clearly smaller than the sensitivity to dynamic variability.