 |
| Titel |
Tropospheric Distribution of Trace Species during the Oxidation Mechanism Observations (OMO-2015) campaign: Model Evaluation and sensitivity simulations |
| VerfasserIn |
Narendra Ojha, Andrea Pozzer, Patrick Jöckel, Horst Fischer, Andreas Zahn, Laura Tomsche, Jos Lelieveld  |
| Konferenz |
EGU General Assembly 2017
|
| Medientyp |
Artikel
|
| Sprache |
en
|
| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 19 (2017) |
| Datensatznummer |
250143159
|
| Publikation (Nr.) |
 EGU/EGU2017-6860.pdf |
|
|
|
|
|
| Zusammenfassung |
| The Asian monsoon convection redistributes trace species, affecting the tropospheric
chemistry and radiation budget over Asia and downwind as far as the Mediterranean. It
remains challenging to model these impacts due to uncertainties, e.g. associated with the
convection parameterization and input emissions. Here, we perform a series of numerical
experiments using the global ECHAM5/MESSy atmospheric chemistry model (EMAC) to
investigate the tropospheric distribution of O3 and related tracers measured during the
Oxidation Mechanism Observations (OMO) conducted during July-August 2015.
The reference simulation can reproduce the spatio-temporal variations to some
extent (e.g. r2 = 0.7 for O3, 0.6 for CO). However, this simulation underestimates
mean CO in the lower troposphere by about 30 ppbv and overestimates mean O3 up
to 35 ppbv, especially in the middle-upper troposphere. Interestingly, sensitivity
simulations with 50% higher biofuel emissions of CO over South Asia had insignificant
effect on CO underestimation, pointing to sources upwind of South Asia. Use of an
alternative convection parameterization is found to significantly improve simulated O3.
The study reveals the abilities as well as the limitations of the model to reproduce
observations and study atmospheric chemistry and climate implications of the monsoon. |
|
|
|
|
|
|