Volumes and Issues  Contents of Issue 6  Special Issue  
Atmos. Chem. Phys. Discuss., 6, 12469-12501, 2006
www.atmos-chem-phys-discuss.net/6/12469/2006/
© Author(s) 2006. This work is licensed
under a Creative Commons License.


Isentropic advection and convective lifting of water vapor in the UT – LS as observed over Brazil (22° S) in February 2004 by in situ high-resolution measurements of H2O, CH4, O3 and temperature

G. Durry1,2, N. Huret3, A. Hauchecorne1, V. Marecal3, J.-P. Pommereau1, R. L. Jones4, G. Held, N. Larsen, and J.-B. Renard3
1Service d'Aéronomie, CNRS and Institut Pierre Simon Laplace, Route des Gatines, Verrière le Buisson cedex, 91371, France
2Groupe de Spectroscopie Moléculaire et Atmosphérique, CNRS and Université de Reims, Moulin de la Housse, B.P. 1039, 51687 Reims Cedex, France
3Laboratoire de Physique et Chimie de l'Environnement, CNRS and Université d'Orléans, 3A Avenue de la Recherche Scientifique, 45071 Orléans cedex 2, France
4Center for Atmospheric Science, University Chemical Laboratory, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, UK

Abstract. The micro-SDLA balloonborne diode laser spectrometer was flown twice from Bauru (22° S, Brazil) in February 2004 during HIBISCUS to yield in situ H2O measurements in the Upper Troposphere (UT) and Lower Stratosphere (LS) and in particular in the Tropical Tropopause Layer (TTL). The overall TTL was found warmer (with a subsaturated cold point near –79°C) and the LS moister compared to former measurements obtained in tropical oceanic conditions. The use of specific balloons with a slow descent, combined with the high-resolution of the laser sensor, allowed us to observe in situ in the UT, the TTL and the LS several thin layers correlated on H2O, CH4, O3, temperature and PV. A component of these layers is associated with the isentropic transport into the UT- LS of extratropical stratospheric air masses. Moreover, the examination of temperature and tracer (CH4, O3) profiles gives insights on the potential contribution of convective transport of H2O in the TTL.

Discussion Paper (PDF, 2061 KB)   Interactive Discussion (Final Response, 5 Comments)

Citation: Durry, G., Huret, N., Hauchecorne, A., Marecal, V., Pommereau, J.-P., Jones, R. L., Held, G., Larsen, N., and Renard, J.-B.: Isentropic advection and convective lifting of water vapor in the UT – LS as observed over Brazil (22° S) in February 2004 by in situ high-resolution measurements of H2O, CH4, O3 and temperature, Atmos. Chem. Phys. Discuss., 6, 12469-12501, 2006.   Bibtex   EndNote   Reference Manager