Journal cover Journal topic
Atmospheric Chemistry and Physics An interactive open-access journal of the European Geosciences Union
Atmos. Chem. Phys., 16, 10489-10500, 2016
© Author(s) 2016. This work is distributed
under the Creative Commons Attribution 3.0 License.
Research article
22 Aug 2016
Tropospheric ozone variability during the East Asian summer monsoon as observed by satellite (IASI), aircraft (MOZAIC) and ground stations
Sarah Safieddine1,a, Anne Boynard1, Nan Hao2, Fuxiang Huang3, Lili Wang4, Dongsheng Ji4, Brice Barret5, Sachin D. Ghude6, Pierre-François Coheur7, Daniel Hurtmans7, and Cathy Clerbaux1,7 1Sorbonne Universités, UPMC Univ. Paris 06, Université Versailles St-Quentin, CNRS/INSU, LATMOS-IPSL, Paris, France
2German Aerospace Center (DLR), Remote Sensing Technology Institute (IMF), Oberpfaffenhofen, Germany
3National Satellite Meteorological Center, China Meteorological Administration, Beijing, China
4LAPC, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, China
5Laboratoire d'Aérologie, Observatoire Midi-Pyrénées, Université Paul Sabatier, CNRS, Toulouse, France
6Indian Institute of Tropical Meteorology, Pashan Rd., Pune-411 008, India
7Spectroscopie de l'Atmosphère, Chimie Quantique et Photophysique, Université Libre de Bruxelles (U.L.B.), Brussels, Belgium
anow at: Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
Abstract. Satellite measurements from the thermal Infrared Atmospheric Sounding Interferometer (IASI), aircraft data from the MOZAIC/IAGOS project, as well as observations from ground-based stations, are used to assess the tropospheric ozone (O3) variability during the East Asian Summer Monsoon (EASM). Six years 2008–2013 of IASI data analysis reveals the ability of the instrument to detect the onset and the progression of the monsoon seen by a decrease in the tropospheric 0–6 km O3 column due to the EASM, and to reproduce this decrease from one year to the other. The year-to-year variability is found to be mainly dependent on meteorology. Focusing on the period of May-August 2011, taken as an example year, IASI data show clear inverse relationship between tropospheric 0–6 km O3 on one hand and meteorological parameters such as cloud cover, relative humidity and wind speed, on the other hand. Aircraft data from the MOZAIC/IAGOS project for the EASM of 2008–2013 are used to validate the IASI data and to assess the effect of the monsoon on the vertical distribution of the tropospheric O3 at different locations. Results show good agreement with a correlation coefficient of 0.73 (12 %) between the 0–6 km O3 column derived from IASI and aircraft data. IASI captures very well the inter-annual variation of tropospheric O3 observed by the aircraft data over the studied domain. Analysis of vertical profiles of the aircraft data shows a decrease in the tropospheric O3 that is more important in the free troposphere than in the boundary layer and at 10–20° N than elsewhere. Ground station data at different locations in India and China show a spatiotemporal dependence on meteorology during the monsoon, with a decrease up to 22 ppbv in Hyderabad, and up to 5 ppbv in the North China Plain.

Citation: Safieddine, S., Boynard, A., Hao, N., Huang, F., Wang, L., Ji, D., Barret, B., Ghude, S. D., Coheur, P.-F., Hurtmans, D., and Clerbaux, C.: Tropospheric ozone variability during the East Asian summer monsoon as observed by satellite (IASI), aircraft (MOZAIC) and ground stations, Atmos. Chem. Phys., 16, 10489-10500, doi:10.5194/acp-16-10489-2016, 2016.
Publications Copernicus
Short summary
The Asian Summer Monsoon has implication on the weather and climate system as well as pollutants concentration over the monsoon regions leading to effects on the global air quality. Our results, combining satellite, aircraft and ground station data, show that tropospheric ozone, decrease during the period May–August over East and South Asia due to the Monsoon. The magnitude of this drop depends largely on meteorology and geographic location.
The Asian Summer Monsoon has implication on the weather and climate system as well as pollutants...