1. WESTERN AFRICA MISSION (WAM): An AURA Collaborative Science Mission Planning Committee: D.J. Jacob, E.V. Browell, W.H. Brune, J.H. Crawford, J.A. Logan, H.B. Singh AURA Validation Workshop Pasadena, March 19-20, 2002

2. WESTERN AFRICA MISSION (WAM) an AURA collaborative science mission OBJECTIVES: To understand the interactions between biomass burning, the biosphere, human activity, lightning, and dust in determining tropospheric ozone and aerosol production over western Africa; To understand the role of deep convection, the monsoon, and other flow patterns in the processing of these emissions; To understand the mechanisms for outflow of ozone, aerosols, and their precursors from western Africa to the global troposphere; To provide Aura tropospheric validation data in a complex and highly variable tropical environment where TOMS appears to experience unresolved difficulties. Opportunity for collaboration with European AMMA (African Monsoon Multidisciplinary Analysis) field campaigns in 2005 (ground stations, light aircraft).

3. Dust Savanna Anthropogenic Biofuel Forest Biomass Burning Ocean Monsoon Flux Harmattan Flux WESTERN AFRICA IS A PARTICULARLY ACTIVE AND COMPLEX REGION OF THE TROPICS Celine Mari, LA Toulouse Biomass Burning Lightning

4. ATSR FIRE COUNTS (1997) Western Africa is one of the world’s most active biomass burning regions: DJF season

5. LARGE DIFFERENCE BETWEEN MODEL AND TOMS TROPOSPHERIC OZONE COLUMNS OVER W. AFRICA GEOS-CHEM - 1997TOMS (CCD)- 1997 JJA SON MAM DJF Martin et al. [2002]

6. OZONE VERTICAL PROFILES OVER ABIDJAN North African Dec-Feb ozone enhancement from biomass burning Is seen by aircraft observations but not by TOMS (Martin et al., 2002) MOZAIC aircraft data GEOS- CHEM TOMS (distributed w/assumed standard profile) Note: in situ observations over and around western Africa are exceedingly few!

7. LIS LIGHTNING FLASHES (2000) Western Africa is one of the world’s most active lightning regions DJF JJA

8. …AND YET MODELS PREDICT MAX. LIGHTNING INFLUENCE ON OZONE OVER S. ATLANTIC YEAR-ROUND Difference between standard and no-lightning GEOS-CHEM simulations Martin et al. [2002]

9. HIGH AFRICAN BIOGENIC VOC EMISSIONS SEEN BY GOME T. Kurosu (SAO) and P. Palmer (Harvard)

10. WESTERN AFRICA IS ONE OF THE DUSTIEST REGIONS ON EARTH

11. DUST OVER WESTERN AFRICA CAN HAVE COMPLEX EFFECTS ON SATELLITE RETRIEVALS SeaWIFS “true-color” data (obtained from R. Husar)

12. INTEGRATED OBSERVATIONAL STRATEGY FOR WAM AURA: Ozone, CO, H 2 O,NO, NO 2, HNO 3, CH4, HCHO, … 3-D CTM forecasts and analyses WB-57 and DC-8 aircraft SATELLITES AIRCRAFT, SONDES, GROUND MODELS Design mission to optimize value of combined AURA/aircraft data set towards addressing mission objectives and testing relevant CTMs; AURA validation is an essential component of process Others: CO 2, aerosols, surface properties, lightning…

13. WAM MISSION PLAN Two aircraft WB-57: vertical profiles to tropopause, convective outflow DC-8: source region characterization, lower-altitude outflow Link with other AURA validation missions WAM will be part of AVE and may link with TC3 Costa Rica deployment; WAM complements TC3 which focuses on cleaner and simpler regions of the tropics. Two seasons winter (Jan-Feb): biomass burning summer or shoulder season (Apr-Oct): monsoon, lightning Bases of operations Ivory Coast, Benin, Senegal (link with European planning) Ancillary measurements Ozonesonde launches, ground-based lidar Coordination with European aircraft, ground-based stations Timing 2005 for summer phase would take advantage of European participation.

14. WAM AIRCRAFT PAYLOADS AND FLIGHT PLANS PAYLOADS –WB-57: AVE payload –DC-8: Remote ozone, aerosol, water vapor Ozone, CO, CO 2, H 2 O, UV, aerosol properties, NO y species, HO x and HO y species, VOCs, ammonia FLIGHT PLANS –Convective flights (WB-57, DC-8): vertical profiles in convective inflow/outflow, contrast to background – Source characterization flights (DC-8) –Chemical outflow and aging flights (DC-8) AURA VALIDATION STRATEGY –Use WB-57 profiling capabilities, support with DC-8 detailed aerosol/chemical payload and lidars.