Southern Hemisphere Additional Ozonesondes (SHADOZ) ozone climatology (2005-2009): Tropospheric and tropical tropopause layer (TTL) profiles with comparisons to OMI-based ozone products

Anne M. Thompson (1) , Sonya K. Miller , Simone Tilmes , Debra W. Kollonige , Jacquelyn C. Witte , Samuel J. Oltmans , Bryan J. Johnson , Masatomo Fujiwara , F. J. Schmidlin , G. J. R. Coetzee , Ninong Komala , Matakite Maata , Maznorizan Bt Mohamad , J. Nguyo , C. Mutai , S.-Y. Ogino , F. Raimundo da Silva , N. M. Paes Leme , Françoise Posny (2) , Rinus Scheele , Henry B. Selkirk , Masato Shiotani , René Stübi , Gilbert Levrat , Bertrand Calpini , Valérie Thouret (3) , Haruo Tsuruta , Jessica Valverde Canossa , Holger Vömel , S. Yonemura , Jorge Andrés Diaz , Nguyen T. Tan Thanh , Hoang T. Thuy Ha

1 Department of Meteorology and Atmospheric Science [PennState]
2 UMR PVBMT - Peuplements végétaux et bioagresseurs en milieu tropical
3 LAERO - Laboratoire d'aérologie

We present a regional and seasonal climatology of SHADOZ ozone profiles in the troposphere and tropical tropopause layer (TTL) based on measurements taken during the first five years of Aura, 2005-2009, when new stations joined the network at Hanoi, Vietnam; Hilo, Hawaii; Alajuela/Heredia, Costa Rica; Cotonou, Benin. In all, 15 stations operated during that period. A west-to-east progression of decreasing convective influence and increasing pollution leads to distinct tropospheric ozone profiles in three regions: (1) western Pacific/eastern Indian Ocean; (2) equatorial Americas (San Cristóbal, Alajuela, Paramaribo); (3) Atlantic and Africa. Comparisons in total ozone column from soundings, the Ozone Monitoring Instrument (OMI, on Aura, 2004-) satellite and ground-based instrumentation are presented. Most stations show better agreement with OMI than they did for EP/TOMS comparisons (1998-2004; Earth-Probe/Total Ozone Mapping Spectrometer), partly due to a revised above-burst ozone climatology. Possible station biases in the stratospheric segment of the ozone measurement noted in the first 7 years of SHADOZ ozone profiles are re-examined. High stratospheric bias observed during the TOMS period appears to persist at one station. Comparisons of SHADOZ tropospheric ozone and the daily Trajectory-enhanced Tropospheric Ozone Residual (TTOR) product (based on OMI/MLS) show that the satellite-derived column amount averages 25% low. Correlations between TTOR and the SHADOZ sondes are quite good (typical r2 = 0.5-0.8), however, which may account for why some published residual-based OMI products capture tropospheric interannual variability fairly realistically. On the other hand, no clear explanations emerge for why TTOR-sonde discrepancies vary over a wide range at most SHADOZ sites.

Domaines: Physique Atmosphérique et Océanique [physics.ao-ph]

Anne M. Thompson, Sonya K. Miller, Simone Tilmes, Debra W. Kollonige, Jacquelyn C. Witte, et al.. Southern Hemisphere Additional Ozonesondes (SHADOZ) ozone climatology (2005-2009): Tropospheric and tropical tropopause layer (TTL) profiles with comparisons to OMI-based ozone products. Journal of Geophysical Research: Atmospheres, 2012, 117 (D23), pp.D23301, 27PP. ⟨10.1029/2011JD016911⟩. ⟨hal-00766889⟩