Status of the Development of a Tropospheric Ozone Product from OMI Measurements Jack Fishman 1, Jerald R. Ziemke 2,3, Sushil Chandra 2,3, Amy E. Wozniak 1,4,5 and John K. Creilson 1,4 1 NASA Langley Research Center 2 NASA Goddard Space Flight Center 3 Goddard Earth Science and Technology Center, University of Maryland Baltimore County 4 SAIC International Inc. 5 Also at NASA Goddard Space Flight Center 10 th OMI Science Team Meeting KNMI DeBilt, Netherlands 16 June 2005

Separate Stratosphere from Troposphere to Compute Tropospheric Ozone Residual (TOR) Heritage of Tropospheric Ozone from Satellites

Other Data Sets Are Required To Separate Tropospheric Ozone from Total Ozone Measurements Previous Studies SAGE: Good Vertical Resolution; Poor Spatial Coverage HALOE: Good Vertical Resolution; Poor Spatial Coverage MLS: Vertical Resolution Only >68 mb; Relatively Good Spatial Coverage Only One Archived Layer below 100 mb SBUV: Poor Vertical Resolution; Good Spatial Coverage Archived Layers: 1000–253 mb; mb; mb Stratospheric Fields Generated from 5 Days of Data Tropopause Heights: Archived Gridded Data Sets 2.5° x 2.5° For Aura Studies HIRDLS: 4° latitude x 5° longitude Tropopause Heights: Use Assimilated Data from DAO Possible Use of OMI Vertical Profiles Averaged Over Each Orbit Derive Tropospheric Ozone Using Convective Cloud Differential Methodology From Original Proposal

SAGE/TOMS Tropospheric Ozone Residual (TOR) Seasonal Depictions Dobson Units

Seasonal Depictions of Climatological Tropospheric Ozone Residual (TOR) December - February September - NovemberJune - August March - May Dobson Units (DU) from Fishman, Wozniak, Creilson, Atmos. Chem. Phys., 3, 2003

Regional Enhancements Not Previously Seen Now Found Comparison of TOMS/SAGE TOR with TOMS/SBUV TOR: Regional Enhancements Not Previously Seen Now Found Dobson Units (DU) TOMS/SBUV TOR: June-July-August Climatology ( ) TOMS/SAGE TOR: June-July-August Climatology ( )

Integrated Tropospheric Ozone (Dobson Units) Tropospheric Ozone Residual (Jun-Aug Climatology) Fishman et al. [2003, ACP, 3, 1453] Measurement of Ozone Precursors such as Nitrogen Dioxide (NO 2 ) on Aura will Provide Important Information that Should Lead to a New Understanding of the Origin and Distribution of Global Ozone (Smog) Pollution

Other Data Sets Are Required To Separate Tropospheric Ozone from Total Ozone Measurements Previous Studies SAGE: Good Vertical Resolution; Poor Spatial Coverage HALOE: Good Vertical Resolution; Poor Spatial Coverage MLS: Vertical Resolution Only >68 mb; Relatively Good Spatial Coverage Only One Archived Layer below 100 mb SBUV: Poor Vertical Resolution; Good Spatial Coverage Archived Layers: 1000–253 mb; mb; mb Stratospheric Fields Generated from 5 Days of Data Tropopause Heights: Archived Gridded Data Sets 2.5° x 2.5° For Aura Studies HIRDLS: 4° latitude x 5° longitude Tropopause Heights: Use Assimilated Data from DAO Possible Use of OMI Vertical Profiles Averaged Over Each Orbit

HIRDLS Daily Profile Coverage Will Provide Sufficient Information to Derive 3-Dimensional Stratospheric Ozone Distribution Down to 1 km Below Tropopause Current SBUV Daily Resolution

Other Data Sets Are Required To Separate Tropospheric Ozone from Total Ozone Measurements Previous Studies SAGE: Good Vertical Resolution; Poor Spatial Coverage HALOE: Good Vertical Resolution; Poor Spatial Coverage MLS: Vertical Resolution Only >68 mb; Relatively Good Spatial Coverage Only One Archived Layer below 100 mb SBUV: Poor Vertical Resolution; Good Spatial Coverage Archived Layers: 1000–253 mb; mb; mb Stratospheric Fields Generated from 5 Days of Data Tropopause Heights: Archived Gridded Data Sets 2.5° x 2.5° For Aura Studies HIRDLS: 4° latitude x 5° longitude HIRDLS Data Not Available: Using MLS Data Tropopause Heights: Use Assimilated Data from DAO Possible Use of OMI Vertical Profiles Averaged Over Each Orbit

Daily Product Derived from OMI/MLS (Plotted as average volume mixing ratio)

Monthly Product Derived from OMI/MLS (Plotted as average volume mixing ratio)

Other Data Sets Are Required To Separate Tropospheric Ozone from Total Ozone Measurements Previous Studies SAGE: Good Vertical Resolution; Poor Spatial Coverage HALOE: Good Vertical Resolution; Poor Spatial Coverage MLS: Vertical Resolution Only >68 mb; Relatively Good Spatial Coverage Only One Archived Layer below 100 mb SBUV: Poor Vertical Resolution; Good Spatial Coverage Archived Layers: 1000–253 mb; mb; mb Stratospheric Fields Generated from 5 Days of Data Tropopause Heights: Archived Gridded Data Sets 2.5° x 2.5° For Aura Studies HIRDLS: 4° latitude x 5° longitude HIRDLS Data Not Available: Using MLS Data Tropopause Heights: Use Assimilated Data from DAO Use Ozone from NOAA’s GFS (Global Forecast System) Model Possible Use of OMI Vertical Profiles Averaged Over Each Orbit

GFS Model Run at t 0-24 to Forecast Stratospheric Column O 3 for t 0 Calculate TOR Product at t 0 Isolate “Hot Spots” and Run Trajectory Ensemble with NOAA’s HYSPLIT Generate Guidance Product for t 0+24 Disseminate Guidance Product to Air Quality Forecasters Providing Guidance Products to Air Quality Forecasters SCO at t 0-24 SCO at t 0 TOR at t 0 TOR at t 0+24 OMI on Aura Total O 3 from OMI

OMI Total Ozone 5-8 Nov 2004

GFS Model Output SCO ( hPa) 4-8 Nov 2004

Calculated TOR 4-8 Nov 2004

HYSPLIT Forward Trajectories Show High TOR on 6-7 November May Have Come from Fire Emissions Several Days Earlier MODIS Aerosol 5 Nov TOR - 6 Nov TOR - 7 Nov Preliminary Results Encouraging! Much More Analysis Still Needed!

OMI/GFS TOR OMI/MLS TOR Comparison of TOR Products:

Weekly OMI/GFS TOR for March

Weekly OMI/GFS TOR for April

Weekly OMI/GFS TOR for May

Daily OMI/GFS TOR for May

Public Release GFS + ClimatologyNative GFS Use of Complete GFS Product Should Improve TOR Current Calculations Use O 3 from GFS 10hPa-100hPa

Other Data Sets Are Required To Separate Tropospheric Ozone from Total Ozone Measurements Previous Studies SAGE: Good Vertical Resolution; Poor Spatial Coverage HALOE: Good Vertical Resolution; Poor Spatial Coverage MLS: Vertical Resolution Only >68 mb; Relatively Good Spatial Coverage Only One Archived Layer below 100 mb SBUV: Poor Vertical Resolution; Good Spatial Coverage Archived Layers: 1000–253 mb; mb; mb Stratospheric Fields Generated from 5 Days of Data Tropopause Heights: Archived Gridded Data Sets 2.5° x 2.5° For Aura Studies HIRDLS: 4° latitude x 5° longitude HIRDLS Data Not Available: Using MLS Data Tropopause Heights: Use Assimilated Data from DAO Using Information from NOAA’s GFS Possible Use of OMI Vertical Profiles Averaged Over Each Orbit Not Tried Yet

Validation of Measurements Challenging Stratospheric Column Ozone Derived from SBUV Agrees with SCO Derived from SAGE Profiles and with Available Ozonesonde Measurements:

Proposed: HIRDLS to Provide Stratospheric O 3 Profiles ~2 km resolution Actual: Using MLS Data to Derive TOR Challenge: Accuracy of Lower Stratospheric Data at Mid-latitudes Proposed: Use DAO to Provide Tropopause Heights Actual: Using GFS to Determine Stratospheric O 3 and Tropopause Heights Challenges: GFS O 3 not “user-friendly” O 3 calculated only from 100 hPa to 10 hPa initially using climatology to complete SCO Proposed: Use OMI Vertical Profiles to Calculate SCO Actual: Have not tried to obtain OMI stratospheric profiles (availability?) Study using SBUV shows good agreement with SAGE & O 3 sondes Proposed: Use Convective Cloud Differential Technique Actual: Preliminary results Tropospheric Ozone from OMI: Where are we?

Tropospheric Ozone from OMI Using CCD Method

Unforeseen Developments Use of Satellite Data to Calculate Tropospheric Data in Near-Real-Time Successfully demonstrated for MODIS to calculate aerosol data Derivation of Tropospheric Ozone Directly from OMI Satellite Measurement Validation: Extremely Difficult for Troposphere

Direct Measurement of Tropospheric Ozone from GOME Recently Demonstrated (Data Courtesy of K. Chance, SAO)

TOMS/SBUV TOR Comparison of Tropospheric Ozone Derived Directly from GOME with TOMS/SBUV TOR GOME (Data Courtesy of K. Chance, SAO)

Validation! Validation! Validation! Extremely Difficult for Troposphere Sensitivity of Backscatter Signal in Lower Troposphere Direct Underflights from Aircraft: Can never be completely synchronous Climatological Comparisons: How meaningful for near-real-time comparisons?

Comparison of TOR with O 3 from UV-DIAL during TRACE-A Transit Flight How do we validate TOR measurements?

One Last Thought: Patience! We’re still a long way from where we would like to be How good did TOMS data look in 1979? OMI data will evolve