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Interannual variability of CO and its relation to long-range transport and biomass burning. Gloudemans 1 , J. de Laat 1,2 , C. Dijkstra 1 , H. Schrijver 1 , I. Aben 1 , G. vd Werf 3 , M. Krol 1,4. 1 SRON Netherlands Institute for Space Research 2 KNMI, 3 VU, 4 WUR.
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Interannual variability of CO and its relation to long-range transport and biomass burning Gloudemans1, J. de Laat1,2, C. Dijkstra1, H. Schrijver1, I. Aben1, G. vd Werf3, M. Krol1,4 1SRON Netherlands Institute for Space Research 2KNMI, 3VU, 4WUR
SCIAMACHY CO retrievals: a real challenge! • CO lines SWIR ~2310-2380 nm, sensitive down to Earth surface where the CO sources are • CO lines are weak and often overlap with strong H2O and CH4 lines • Important instrument calibration issues further complicate the CO retrievals, in particular: • Presence of ice layer on the detector • Increasing number of dead/bad detector pixels (radiation damage) • Surface reflectance SWIR: • Oceans <0.01 • Densely vegetated areas ~0.05 • Dry desert regions >0.5 • Clouds ~0.3-0.5 ESA Living Planet Symposium - 27 June – 2 July 2010 - Bergen
ESA Living Planet Symposium - 27 June – 2 July 2010 - Bergen Enhanced carbon monoxidefrom Greek forest fires OMI aerosol index
SCIAMACHY CO Red: high clouds, small cloud top pressures Blue: low clouds, large cloud top pressures Cloud top height (hPa) Gloudemans et al. (2009) ACP, 9, 3799-3813 ESA Living Planet Symposium - 27 June – 2 July 2010 - Bergen
ESA Living Planet Symposium - 27 June – 2 July 2010 - Bergen Validation with ground-based data From: De Laat et al. (2010), AMTD, in press Thanks to NDACC, R.Sussmann,T.Borsdorff, and all other data providers for providing ground-based CO column data • Use SWIR CH4 as cloud top height estimate • Good agreement between CH4 cloud top height and FRESCO+ cloud top height
ESA Living Planet Symposium - 27 June – 2 July 2010 - Bergen SCIA - GBS Validation with ground-based data Time-dependent negative bias in Southern Hemisphere South of ~40oS From: De Laat et al. (2010), AMTD, in press • Use SWIR CH4 as cloud top height estimate • Good agreement between CH4 cloud top height and FRESCO+ cloud top height
ESA Living Planet Symposium - 27 June – 2 July 2010 - Bergen Gloudemans et al. (2009) ACP, 9, 3799-3813
Transport of biomass-burning CO Gloudemans et al. (GRL, 2006) ESA Living Planet Symposium - 27 June – 2 July 2010 - Bergen
ESA Living Planet Symposium - 27 June – 2 July 2010 - Bergen South American emissions Van der Werf et al. (ACP, 2006) Gloudemans et al. (GRL, 2006) • S-America biomass-burning (BB) emissions much higher in 2004 • modeled emissions possibly still too low • signal BB S-America primarily from S-America, peak Sept. • signal BB Africa primarily from Africa, with a contribution from S-America which lags in time ~few weeks. • in Australia, depending on the location the main contribution sometimes originates from BB in S-America !!
Interannual variation in biomass-burning SCIAMACHY CO South America Central Australia Central Africa —South America …Central Africa Torres et al. (ACP, 2010) ESA Living Planet Symposium - 27 June – 2 July 2010 - Bergen
ESA Living Planet Symposium - 27 June – 2 July 2010 - Bergen Interannual variability over Indonesia Gloudemans et al. (2009) ACP, 9, 3799-3813
ESA Living Planet Symposium - 27 June – 2 July 2010 - Bergen http://www.nasa.gov/centers/goddard/news/topstory/2007/elnino_wildfire.html Gloudemans et al. (2009)
ESA Living Planet Symposium - 27 June – 2 July 2010 - Bergen Gloudemans et al. (2009) ACP, 9, 3799-3813
ESA Living Planet Symposium - 27 June – 2 July 2010 - Bergen SCIAMACHY CO and transport of Asian pollution Variability SCIAMACHY CO very similar to MOPITT Turquety et al. (2008, ACP) De Laat et al. (2010, JGR) • Clouds are bright sufficient signal to noise • Simultanously measured CH4 column: good proxy for cloud top height. • only use low clouds • Annual 1x1 mean • SCIA CO columns above cloud + TM4 below cloud = CO total column • SCIA CO columns above cloud only • TM4 above cloud • MOPITT total column – bias due to different sensitivities (clouds, AVK, a priori,…) • Preliminary, qualitative comparison only • Detailed quantitative comparison of SCIAMACHY and MOPITT is in progress
Conclusions • SCIAMACHY can measure CO over the oceans above low clouds • Instrument noise error good indication of overall error in CO • SCIAMACHY CO agrees well with ground-based observations • Time-dependent bias detected in Southern Hemisphere • Enhanced CO due to biomass burning, the corresponding long-range transport and their inter-annual variation are clearly seen: clear contribution of CO emitted by South-American forest fires to CO enhancements over Australia : >50% over central Australia in 2004 • Long-range transport of pollution from Asia clearly seen • Interannual variations can be studied: year-to-year changes in good agreement with MOPITT, models, FTIR, .... ESA Living Planet Symposium - 27 June – 2 July 2010 - Bergen
Quick look of SCIAMACHY CO data with Google Earth: http://www.sron.nl/google_earth www.sciamachy.org/products 2003-2007 data available, more years and new retrieval version under way (poster 008-D2) contact : a.gloudemans@sron.nl
ESA Living Planet Symposium - 27 June – 2 July 2010 - Bergen SCIAMACHY CH4 cloud top pressures Low clouds: surface – 800 hPa High clouds: pressure <800 hPa Gloudemans et al. (2009)
Retrieval version: IMLM v7.4 Gloudemans et al. (2009) ACP, 9, 3799-3813 ESA Living Planet Symposium - 27 June – 2 July 2010 - Bergen
ESA Living Planet Symposium - 27 June – 2 July 2010 - Bergen SCIAMACHY CO over the oceans: clouds Red: high clouds, small cloud top pressures Blue: low clouds, large cloud top pressures Gloudemans et al. (2009) Cloud top height (hPa) • Use SWIR CH4 as cloud top height estimate • Good agreement between CH4 cloud top height and FRESCO+ cloud top height