 |
| Titel |
Modelling the Diurnal Variation of Lower Stratospheric ClO in the Arctic Vortex and Comparison with Airborne Observations |
| VerfasserIn |
Maryam Khosravi, Jo Urban, Donal Murtagh, Armin Kleinböhl |
| Konferenz |
EGU General Assembly 2010
|
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 12 (2010) |
| Datensatznummer |
250040981
|
|
|
|
|
|
| Zusammenfassung |
| The kinetics of the ClO dimer cycle plays a major role for ozone loss in the polar vortices in
winter/spring. Our understanding of polar ozone loss and the diurnal variation of ClO and O3
rely on reaction-kinetics derived from laboratory studies, in particular with respect
to the thermal equilibrium between ClO and Cl2O2 and the photolysis of Cl2O2.
The aim of this study is to investigate the diurnal variation of modelled ClO in the
Arctic lower stratosphere during winter/spring and to test the latest kinetics data
which have become available from recent studies and the effects of their potential
errors.
In this study, the ClO mixing ratio profiles from a photochemical model and observational
data from an aircraft measurement have been compared. The ASUR (Airborne Submillimeter
SIS Radiometer) instrument, operated on a FALCON airplane, detects thermal emission of
ClO in the Arctic vortex. The project was a cooperation of the University of Bremen
(Germany) and the Space Research Organization of Netherlands (SRON Groningen). The
measurement flights were made from Kiruna, Sweden inside the Arctic vortex, during
February and March 1996 and 1997. The model calculations were carried out with a
photochemical box model (MISU1D) that calculates the diurnal variation of trace species in
the middle atmosphere using radiative transfer and chemical reaction rate data. The rates and
uncertainties from the latest laboratory measurements have been combined and the model
results have been compared with the observations to evaluate the best combinations. |
|
|
|
|
|
|