The Budget of Tropospheric Ozone During TOPSE Louisa
The Budget of Tropospheric Ozone During TOPSE Louisa Emmons, Xuexi Tie, Guy Brasseur, Jean-François Lamarque, Douglas Kinnison, Andrzej Klonecki, Peter Hess, Brian Ridley - NCAR/ACD Larry Horowitz - GFDL/Princeton Edward Browell - NASA Langley John Merrill - URI John Hennessy - ECMWF
MOZART-2 Model for Ozone and Related chemical Tracers • Chemical Transport Model driven by ECMWF meteorological fields • Simulations for Jan. 15 – June 15, 2000 • Resolution: 2 lat x 2 lon x 60 vertical levels to 0. 1 h. Pa • Model description and evaluation: poster by Larry Horowitz Wed pm • N 2 O 5 + H 2 O on aerosols: =0. 04 (improved NOx at winter high-latitudes): poster by Xuexi Tie Wed pm
Model-Data comparisons • MOZART results agree well with the observations of ozone from the aircraft and ozonesondes • NOx is slightly underestimated by MOZART • Observations: – In situ O 3 and NOx TOPSE data (B. Ridley) – Ozonesondes (J. Merrill and WOUDC)
Flight Track Comparisons: in situ O 3 (B. Ridley)
Flight Track Comparisons NOx (B. Ridley)
Binned Data and MOZART in situ O 3 Data MOZART
Binned Data and MOZART NOx Data MOZART
MOZART and Ozonesondes
TOPSE Ozone Budget • MOZART diagnostics: – Change in O 3 due to chemistry and transport is saved for each model time step and grid box – Stratospheric O 3 tracer is set equal to O 3 in the stratosphere and destroyed in the troposphere through photochemical loss and surface deposition
Ozone over North America from MOZART
Ozone Budget over North America from MOZART
Ozone Budget over North America Components of Chemistry and Transport
Ozone Budget over the Northern Hemisphere
Ozone Budget over the Northern Hemisphere
Ozone over North America Comparison of Different NOx Cases
Change in O 3 - Chemistry
Change in O 3 – Surface Deposition
Summary • The northern spring maximum in tropospheric O 3 is observed in the MOZART simulations. • Analysis of the model diagnostics indicate the maximum is due to, first, an increase in stratospheric input, followed by increase in chemical production. • The net transport is due to the balance of stratospheric influx with deposition, both large terms increasing through Spring.
Acknowledgements We gratefully acknowledge ECMWF for providing the met. fields for the MOZART simulations.
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