Status of Central European NO 2 products

1. Status of Central European NO2 products Dominik Brunner, Daniel Schaub, Brigitte Buchmann Empa, Swiss Federal Laboratories for Materials Testing and Research Dübendorf, Switzerland Andrea Petritoli Istituto di Scienze dell'Atmosfera e del Clima, ISAC-CNR Bologna, Italy

2. Embedding within TEMIS WP 2.2 Global NO2 product End user Global tropospheric NO2 columns WP 2.3 Regional NO2 product Extract: regional tropospheric NO2 columns Add: Auxiliary data (Meteo, DOAS) + Validation of regional NO2 columns

3. Overview of products Region of interest (ROI): Alpine Region and Po valley Product 1: Tailored picture covering the ROI Product 2: Data files (ASCII) for users containing NO2 column data (pixel values), cloud flag and cloud parameters

4. Overview of products Region of interest (ROI): Alpine Region and Po valley • Product 3: • Trajectory calculation* for pixels in ROI (potential source regions) • Trajectory arrival points covering the whole pixel * • - Analysed wind fields from ECMWFat 6 hr temporal and 1° x 1° geographical resolution • 3-D kinematic 4-day backward trajectories calculated with Lagranto (Wernli and Davies, 1997)

5. Overview of products Region of interest (ROI): Alpine Region and Po valley Product 4: Ground-based DOAS NO2 vertical profiles retrieved at Mt. Cimone and Bologna  Ground-based data in ASCII and images Product 5: Validation (for specific periods) with ground-based measurements and meteorological information Petritoli et al. (2004)

6. Application examples Example 1: Gridded seasonal or (multi-) annual mean distributions GOME 1996-2003 meanclear sky distribution SCIAMACHY 2003-2005 meanclear sky distribution Schaub et al., ACPD 2007

7. Application examples Example 2: NOx source region attribution Air pollution in Po valley on 23 June 2003

8. Application examples Example 2: NOx source region attribution Air pollution in Po valley on 23 June 2003: Origin of air arriving in pollution pixels at different levels 700 hPa 750 hPa 800 hPa 850 hPa 900 hPa 950 hPa

9. Application examples Example 2: NOx source region attribution Air pollution in Po valley on 23 June 2003: Maps of residence time of column air in PBL NO2 VTC < 15 x 1015 molec/cm2 NO2 VTC > 15 x 1015 molec/cm2 Hatched areas indicate positions of satellite pixels

10. Application examples Example 2: NOx source region attribution Air pollution in Po valley on 23 June 2003: Maps of residence time of column air in PBL

11. Application examples Example 3: Validation of GOME vertical tropospheric NO2 columns with ground-based in situ measurements .. for TEMIS GOME tropospheric NO2 columns 1997-2003. Schaub et al. (ACP, 2006) Measurement sites

12. Status of product availability Website moved to: http://temis.empa.ch Product 1:tailored picture for each overpassGOME: 01/01 1997 – 21/06 2003, SCIA: 01/01 2003 – 17/09 2006 Product 2:ASCII data files (regional NO2 and auxiliary information)GOME: 13/03 1996 – 21/06 2003, SCIA: 07/01 2003 – 30/09 2005 Product 3:Representativity flag and picture of potential source regionsGOME: 1997 SCIA: 01/01 2003 – 31/03 2004 Product 4:Ground-based DOAS NO2 vertical profiles from Mt. Cimone and Bologna (ASCII data file, image) and slant column within the tropospheric layer (46 m - 2165 m asl)2003 Product 5:Validation with ground-based measurements and meteorological information (images and quality flags). Three publications (Petritoli et al., 2003; Schaub et al., 2006, 2007)

13. Application examples Example 3: Comparison of SCIAMACHY vertical tropospheric NO2 columns with a high resolution NOx emissions inventory .. for TEMIS SCIAMACHY tropospheric NO2 columns 2003-2005. Schaub et al. (ACPD, 2007) NOx emissions inventory SCIA pixel