TY  - JOUR
A1  - Hobe, Marc von
A1  - Bekki, Slimane
A1  - Borrmann, Stephan
A1  - Cairo, Francesco
A1  - D'Amato, Francesco
A1  - Di Donfrancesco, Guido
A1  - Dörnbrack, Andreas
A1  - Ebersoldt, Andreas
A1  - Ebert, Martin
A1  - Emde, Claudia
A1  - Engel, Ines
A1  - Ern, Manfred
A1  - Frey, Wiebke
A1  - Grießbach, Sabine
A1  - Grooß, Jens-Uwe
A1  - Gulde, Thomas
A1  - Günther, Gebhard
A1  - Hösen, Maria Elisabeth
A1  - Hoffmann, Lars
A1  - Homonnai, Viktoria
A1  - Hoyle, Christopher Robert
A1  - Isaksen, I. S. A.
A1  - Jackson, David R.
A1  - Jánosi, Imre M.
A1  - Kandler, Konrad
A1  - Kalicinsky, Christoph
A1  - Keil, Andrea
A1  - Khaykin, Sergey M.
A1  - Khosrawi, Farahnaz
A1  - Kivi, Rigel
A1  - Kuttippurath, Jayan
A1  - Laube, Johannes Christian
A1  - Lefèvre, Franck
A1  - Lehmann, Ralph
A1  - Ludmann, Sabrina
A1  - Luo, Beiping P.
A1  - Marchand, Marion
A1  - Meyer, Jessica
A1  - Mitev, Valentin
A1  - Molleker, Sergej
A1  - Müller, Rolf
A1  - Oelhaf, Hermann
A1  - Olschewski, Friedhelm
A1  - Orsolini, Yvan
A1  - Peter, Thomas
A1  - Pfeilsticker, Klaus
A1  - Piesch, Christof
A1  - Pitts, Michael C.
A1  - Poole, Lamont R.
A1  - Pope, Francis D.
A1  - Ravegnani, Fabrizio
A1  - Rex, Markus
A1  - Riese, Martin
A1  - Röckmann, Thomas
A1  - Rognerud, Bjørg
A1  - Roiger, Anke
A1  - Rolf, Christian
A1  - Santee, Michelle L.
A1  - Scheibe, Monika
A1  - Schiller, Cornelius
A1  - Schlager, Hans
A1  - Siciliani de Cumis, Matteo
A1  - Sitnikov, Nikolay
A1  - Søvde, Ole Amund
A1  - Spang, Reinhold
A1  - Spelten, Nicole
A1  - Stordal, Frode
A1  - Sumińska-Ebersoldt, Olga
A1  - Viciani, Silvia
A1  - Volk, C.-Michael
A1  - vom Scheidt, Marcel
A1  - Ulanovski, Alexey
A1  - Gathen, Peter von der
A1  - Walker, Kaley A.
A1  - Wegner, Tobias
A1  - Weigel, Ralf
A1  - Weinbruch, Stephan
A1  - Wetzel, Gerald
A1  - Wienhold, Franck  G.
A1  - Wintel, Johannes
A1  - Wohltmann, Ingo
A1  - Woiwode, Wolfgang
A1  - Young, Isla A. K.
A1  - Yushkov, Vladimir
A1  - Zobrist, Bernhard
A1  - Stroh, Fred
T1  - Reconciliation of essential process parameters for an enhanced predictability of Arctic stratospheric ozone loss and its climate interactions
T2  - Atmospheric chemistry and physics / Discussions
N2  - Significant reductions in stratospheric ozone occur inside the polar vortices each spring when chlorine radicals produced by heterogeneous reactions on cold particle surfaces in winter destroy ozone mainly in two catalytic cycles, the ClO dimer cycle and the ClO/BrO cycle. Chlorofluorocarbons (CFCs), which are responsible for most of the chlorine currently present in the stratosphere, have been banned by the Montreal Protocol and its amendments, and the ozone layer is predicted to recover to 1980 levels within the next few decades. During the same period, however, climate change is expected to alter the temperature, circulation patterns and chemical composition in the stratosphere, and possible geo-engineering ventures to mitigate climate change may lead to additional changes. To realistically predict the response of the ozone layer to such influences requires the correct representation of all relevant processes. The European project RECONCILE has comprehensively addressed remaining questions in the context of polar ozone depletion, with the objective to quantify the rates of some of the most relevant, yet still uncertain physical and chemical processes. To this end RECONCILE used a broad approach of laboratory experiments, two field missions in the Arctic winter 2009/10 employing the high altitude research aircraft M55-Geophysica and an extensive match ozone sonde campaign, as well as microphysical and chemical transport modelling and data assimilation. Some of the main outcomes of RECONCILE are as follows: (1) vortex meteorology: the 2009/10 Arctic winter was unusually cold at stratospheric levels during the six-week period from mid-December 2009 until the end of January 2010, with reduced transport and mixing across the polar vortex edge; polar vortex stability and how it is influenced by dynamic processes in the troposphere has led to unprecedented, synoptic-scale stratospheric regions with temperatures below the frost point; in these regions stratospheric ice clouds have been observed, extending over >106km2 during more than 3 weeks. (2) Particle microphysics: heterogeneous nucleation of nitric acid trihydrate (NAT) particles in the absence of ice has been unambiguously demonstrated; conversely, the synoptic scale ice clouds also appear to nucleate heterogeneously; a variety of possible heterogeneous nuclei has been characterised by chemical analysis of the non-volatile fraction of the background aerosol; substantial formation of solid particles and denitrification via their sedimentation has been observed and model parameterizations have been improved. (3) Chemistry: strong evidence has been found for significant chlorine activation not only on polar stratospheric clouds (PSCs) but also on cold binary aerosol; laboratory experiments and field data on the ClOOCl photolysis rate and other kinetic parameters have been shown to be consistent with an adequate degree of certainty; no evidence has been found that would support the existence of yet unknown chemical mechanisms making a significant contribution to polar ozone loss. (4) Global modelling: results from process studies have been implemented in a prognostic chemistry climate model (CCM); simulations with improved parameterisations of processes relevant for polar ozone depletion are evaluated against satellite data and other long term records using data assimilation and detrended fluctuation analysis. Finally, measurements and process studies within RECONCILE were also applied to the winter 2010/11, when special meteorological conditions led to the highest chemical ozone loss ever observed in the Arctic. In addition to quantifying the 2010/11 ozone loss and to understand its causes including possible connections to climate change, its impacts were addressed, such as changes in surface ultraviolet (UV) radiation in the densely populated northern mid-latitudes.
Y1  - 2012
UR  - http://publikationen.ub.uni-frankfurt.de/frontdoor/index/index/docId/29193
UR  - https://nbn-resolving.org/urn:nbn:de:hebis:30:3-291936
UR  - www.atmos-chem-phys-discuss.net/12/30661/2012/
SN  - 1680-7367
SN  - 1680-7375
N1  - © Author(s) 2012. This work is distributed under the Creative Commons Attribution 3.0 License.
VL  - 12
SP  - 30661
EP  - 30754
PB  - European Geosciences Union
CY  - Katlenburg-Lindau
ER  -