1 / 15

Intercontinental Source Attribution of Ozone Pollution at Western U.S. Sites Using an Adjoint Method

Intercontinental Source Attribution of Ozone Pollution at Western U.S. Sites Using an Adjoint Method. Lin Zhang, Daniel J. Jacob, Monika Kopacz Harvard University Daven K. Henze University of Colorado at Boulder Kumaresh Singh Virginia Polytechnic Institute of State University

vanna
Download Presentation

Intercontinental Source Attribution of Ozone Pollution at Western U.S. Sites Using an Adjoint Method

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Intercontinental Source Attribution of Ozone Pollution at Western U.S. Sites Using an Adjoint Method Lin Zhang, Daniel J. Jacob, Monika Kopacz Harvard University Daven K. Henze University of Colorado at Boulder Kumaresh Singh Virginia Polytechnic Institute of State University Dan A. Jaffe University of Washington-Bothell The 8th Annual CMAS Conference (October 19, 2009)

  2. Intercontinental influence of ozone

  3. Asian 2006 NOx emissions constrained from OMI Asian NOx anthropogenic emissions for the year 2000 from Streets et al. [2003] 2 x 2000 Asian NOx emissions OMI NO2 retrieval from KNMI • Comparison of GEOS-Chem simulation (Global CTM; 2ºx2.5º) for spring 2006 with OMI NO2 tropospheric column observations indicates a factor of 2 increase of Asian anthropogenic NOx emissions from 2000 to 2006 • Some of the corrections (e.g. Japan and Korea) may reflect an underestimation in the prior emissions inventory. Zhang et al., 2008

  4. TES and AIRS observations of a transpacific plume May 5 May 6 May 7 A May 8 B A May 9 2006 B TES on the Aura satellite GEOS-Chem Global CTM (2ºx2.5º) AIRS on the Aqua satellite CO columns Zhang et al., 2008

  5. Impact of Asian emissions on U.S. surface ozone Data from Dan Jaffe Surface O3 enhancements from Asian anthropogenic emissions for spring 2006 O3 measurements at Mt. Bachelor (44oN, 122oW, 2.7 km, in central Oregon) 54 ± 10 53 ± 8 9.4 ± 2.5 1 – 5 ppbv 2000-2006 rise in Asian emissions increased U.S. surface ozone by 1-2 ppbv in the West. Zhang et al., 2008

  6. Forward vs. adjoint sensitivity analysis for source attribution Forward Model (source-oriented) Changes of concentration winds Perturbation at source region t0 tn Adjoint Model (receptor-oriented) Concentration at the receptor winds area of possible origin t0 tn

  7. Ozone observations at the western U.S sites For the period of April 17 - May 15, 2006 MBO (2.7 km) 54 ± 10 TH (sea level) 53 ± 9 13 ± 3.6 41 ± 7 observation GEOS-Chem 43 ± 5 8.4 ±1.4 Tagged ozone produced over Asia Tagged ozone simulation uses a linearized chemistry driven by ozone production rates and loss frequencies saved from the standard simulation.

  8. Adjoint sensitivity for ozone at MBO on May 10 Sensitivity of ozone concentration at MBO on May 10, 2006 at 18 UT to ozone fields at earlier time steps (May 3 - May 10, 2006) Adjoint computes the sensitivity at the model resolution over the history of air parcels reaching the site.

  9. Source attribution of ozone pollution episodes Integrated sensitivity to ozone production Time evolution of sensitivity MBO: May 1, 2006 MBO: May 10, 2006 Decomposition of Asian PAN • The May1 plume took a more northerly and higher-altitude route than the May 10 plume, and thus had less production over the Pacific. • Maximum Asian influence for the two events occurs at time lags of 8-11 days

  10. Mean conditions at MBO and TH MBO: INTEX-B mean (Apr 17-May 15, 2006) MBO (2.7 km) TH (sea level) TH: INTEX-B mean This study attributes ozone sources based on production regions instead of precursor emissions. Use of the adjoint of full chemistry mechanism can improve. Zhang et al., 2009

  11. Tropospheric ozone from TES and OMI on Aura 2006 tropospheric ozone data at 500 hPa averaged on 4ox5o resolution OMI (UV) Data from Xiong Liu (NASA/GSFC) TES (IR) V003 data

  12. Using GEOS-Chem for intercomparison between TES and OMI 2006 tropospheric ozone data at 500 hPa averaged on 4ox5o resolution OMI (UV) Data from Xiong Liu (NASA/GSFC) GEOS-Chem simulation with TES vs. OMI averaging kernels TES (IR) V003 data Zhang et al., in prep.

  13. Using satellite observations to diagnose model errors For 2006 and averaged on 4ox5o resolution Regions with the bias between TES and OMI larger than 10 ppbv are masked as black. Model is too low over the tropics, and too high in the extra-tropics.

  14. Thank you!

  15. Dilution of Asian ozone plume during entrainment MBO: May 10, 2006 8 days TH: May 12, 2006 10 days 15 ppbv vs. 5 ppbv integrated over time lags of 5-20 days A factor of 3 dilution effect as the Asian plume mixed down to the surface.

More Related