Formaldehyde columns from GOME as a proxy for biogenic emissions over Europe

1. Formaldehyde columns from GOME as a proxy for biogenic emissions over Europe 2nd EGU General Assembly Vienna, April 24-29, 2005 Università degli Studi dell’Aquila – CETEMPS L’Aquila, ITALY http://cetemps.aquila.infn.it/ Gabriele Curci, Guido Visconti Paul I. Palmer, Tzung-May Fu Atmospheric Chemistry Modeling Group Harvard University U. L’Aquila CETEMPS

2. OUTLINE • European Biogenic Emissions • Formaldehyde column over Europe as seen by GOME and GEOS-CHEM • Inverting the GOME HCHO column for Isoprene emissions • Conclusions and Outlook

3. EUROPE FACTSHEET • 7% world area • 33% forest • 43% agriculture • 24% other • 13% population (680 mil.) • 30% CO2 emissions • 20% NOx and VOC • 40 countries • Heavily man-shaped Cold-Arctic Continental [Simpson et al., JGR 1999] Mediterranean Only continent where ANTHRO > BIO emissions

4. EUROPEAN BIOGENIC EMISSIONS NMVOC: 13 Tg yr-1 NOx: 140-1500 Tg yr-1 GEOS-CHEM Isoprene Column in Summer • Unimportant on a global scale (7% area) • Local importance: Mediterranean, East, Scandinavia • Bio VOCs + anthro NOx: emission abatement strategies GEIA Emissions • Biogenic emission inventories highly uncertain: up to a factor of 5! • Many countries • Few observations • Different flora and fauna with respect to North America [Simpson et al., JGR 1995]

5. kHCHOHCHO EVOC = _______________ kVOCYieldVOCHCHO hours WHCHO hours Isoprene HCHO h, OH OH a-pinene propane VOC 100 km Distance downwind VOC source RELATING HCHO COLUMN TO VOC EMISSIONS [Palmer et al., 2001, 2003]

6. INVERTING GOME HCHO COLUMN FOR ISOPRENE EMISSIONS GOME Exploit the fast oxidation of isoprene to mark source regions looking at its product formaldehyde (HCHO) where the biogenic emissions > other HCHO column GOME vertical column 340x40 km2 res. global coverage 3 days GOME “slant” column GOME isoprene inventory Air Mass Factor GEOS-CHEM CTM model Harvard University [Bey et al. 2001, Martin et al. 2002] EISOPRENE HCHO col. [Palmer et al., 2001, 2003]

7. WHAT CONTROLS HCHO COLUMN IN EUROPE? v7-01-02 GEOS-CHEM HCHO Column in Summer / NO ISOP NO ANTHRO • Biogenic control of HCHO column: • Eastern Europe • Northern Europe • Iberian Peninsula • Turkey 0.4 1 1.2 (GEIA Emissions) ANTHROPOGENIC CONTROL BIOGENIC CONTROL

8. NO CLEAR BIOGENIC SIGNATURE IN GOME HCHO VERTICAL COLUMN AS IN THE GEOS-CHEM MODEL GOME GEOS-CHEM JUL 97 r = 0.50 AUG 97 r = 0.46

9. GOME HCHO COLUMN IS QUALITATIVELY CONSISTENT WITH THE UPDATED MEGAN BIOGENIC INVENTORY MEGAN Isoprene Emissions July 2000 [Guenther et al.] GOME HCHO - July 1997 GEOS-CHEM (GEIA) Isoprene Emissions - July 1997

10. HCHO/NO2 COLUMN RATIO SHOWS ANTHROPOGENIC EMISSIONS INFLUENCE Also following indications by Martin et al., [2003]: GOME HCHO column could be used as a proxy for isoprene emissions on Eastern Europe GOME HCHO and NO2 data: P. Palmer, M. Fu, R. Martin, K. Chance, T. Kurosu NOx-sat NOx-sens

11. ISOPRENE EMISSIONS FROM GOME OVER EASTERN EUROPE - JULY 1997 GEOS-CHEM 0.4 Tg C Relationship Isoprene Emissions and HCHO Column from the model GOME 0.2 Tg C Formaldehyde Column non-isoprene contribution Isoprene Emissions

12. CONCLUSIONS AND OUTLOOK • Formaldehyde column from GEOS-CHEM (GEIA) differs from GOME over Europe • Use of GOME data as constraint on European isoprene emissions indicates a reduction of the flux. This is consistent with recent work (e.g. MEGAN) • To do next: • Careful estimate of the errors of the inversion method • Estimate isoprene emissions country by country for comparison with Simpson et al. [1999] • MEGAN inventory into the model • Seasonal cycle • Asses contribution of biomass burning over Greece and South Italy to HCHO column • Comparison of GOME HCHO with campaign data (MINOS, FORMAT)

13. THE ENDThanks for the attention! Gabriele Curci http://www.aquila.infn.it/people/Gabriele.Curci.html/ Università degli Studi dell’Aquila – CETEMPS L’Aquila, ITALY http://cetemps.aquila.infn.it/ U. L’Aquila CETEMPS