OMI Overview Prof Dr Pieternel Levelt KNMI TUE

OMI Overview Prof. Dr. Pieternel Levelt KNMI, TUE The Netherlands OMI Zoom mode 12 x 13 km 2 Mexico City and suburbs OMI NO 2, January 20, 2005 Courtesy: Veefkind, KNMI

International OMI Team International OMI Science team • • • PI (KNMI): P. F. Levelt dep. PI (KNMI): J. P. Veefkind co-PI (FMI) J. Tamminen US ST Leader (NASA GSFC): P. K. Bhartia …. And about 60 - 80 scientists OMI is now also a third party Industry mission from ESA • Dutch: DS, TNO-TPD, SRON • Finnish: VTT, Patria • USA: Northrop GES USA Dutch, Finnish and US Space Agencies • NIVR, FMI and NASA • OMI is a Dutch-Finnish Instrument on the NASA spacecraft EOS-Aura Prof. Dr. P. F. Levelt, KNMI, TUE, June 11, 2008, NIVR Launch: July 15, 2004

Ozone hole 2007 Dutch National Geographic November 2008 Instruments in The Netherlands Prof. Dr. P. F. Levelt, KNMI, TUE, June 11, 2008, NIVR

Prof. Dr. P. F. Levelt, KNMI, TUE, June 11, 2008, NIVR

OMI NO 2 Weekly Cycle over The Netherlands Period Dec 2004 - Nov 2005, Normalized for Monday Prof. Dr. P. F. Levelt, KNMI, TUE, June 11, 2008, NIVR

Daily OMI Air Pollution Observations (1) Tuesday Wednesday Tropospheric NO 2 for Tue-6, Wed-7, Thu-8 and Fri-9 May 2008. Image courtesy: Quintus Kleipool (KNMI) Thursday Prof. Dr. P. F. Levelt, KNMI, TUE, June 11, 2008, NIVR Friday

Daily OMI Air Pollution Observations (2) Saturday Sunday Tropospheric NO 2 for Sat-10, Sun-11, Mon-12 and Tue-13 May 2008, including the Pentecost weekend (11 -12 May). Image courtesy: Quintus Kleipool (KNMI) Monday Prof. Dr. P. F. Levelt, KNMI, TUE, June 11, 2008, NIVR Tuesday

Orbit choice : first data on diurnal cycle from space SCIAMACHY and OMI at resp. 10: 00 and 13: 30 local time overpass Courtesy: K. F. Boersma et al. Prof. Dr. P. F. Levelt, KNMI, TUE, June 11, 2008, NIVR

Air Quality Greek Forest fires in august 2007: enhanced aerosols, NO 2 and CO from OMI and SCIAMACHY OMI aerosol (right) and NO 2 (below) Greek Forest fires in august 2007: enhanced aerosols, NO 2 and CO from OMI and SCIAMACHY Prof. Dr. P. F. Levelt, KNMI, TUE, June 11, 2008, NIVR

SO 2 Mount Etna 13, 14, 15 and 1 May 2008 Carn et al. Prof. Dr. P. F. Levelt, KNMI, TUE, June 11, 2008, NIVR

OMI cloud “top” pressure With Cloud. Sat, we can examine radiative transfer in realistic extended clouds and confirm the hypothesis. OMI cloud pressures MODIS cloud-top pressures Layer optical depths derived from MODIS/Cloud. Sat. Profile # 1 2 3 4 5 Cloudsat radar reflectivities Slide from Vassilkov, NASA GSFC. Prof. Dr. P. F. Levelt, KNMI, TUE, June 11, 2008, NIVR Cloud pressures simulated from these data

HCHO Back up Trop O 3 October 2005: collection 3 Prof. Dr. P. F. Levelt, KNMI, TUE, June 11, 2008, NIVR Glyoxal NO 2

Ground Based In-Situ Data • LML Dutch air quality network, www. rivm. nl/lml • Regional, City and Street stations • Mean yearly value per station for 12: 00 to 14: 00 hrs Prof. Dr. P. F. Levelt, KNMI, TUE, June 11, 2008, NIVR

Comparison with the LML Prof. Dr. P. F. Levelt, KNMI, TUE, June 11, 2008, NIVR

Zoom-in over France Cities of the size >100, 000 habitants Prof. Dr. P. F. Levelt, KNMI, TUE, June 11, 2008, NIVR

Detection Limit of Tropospheric NO 2 Area observed 60 x 30 km 2 The detection limit is defined as the minimum difference in tropospheric NO 2 in a yearly mean that is statistically meaningful. Smaller values are better SCIA GOME-2 Prof. Dr. P. F. Levelt, KNMI, TUE, June 11, 2008, NIVR OMI

Aura Spacecraft • Aura FMU anomaly • Aura rephasing Before re-phasing See presentation Jacques Claas today After re-phasing De Bilt OMI monthly spatial zoom-in measurements Washington Prof. Dr. P. F. Levelt, KNMI, TUE, June 11, 2008, NIVR

Instrument and calibration status • OMI instrument is very stable • OMI operations 99, 9 % • Calibration daily OPF updates for dark current corrections: Collection 3 Anomalies OMI: • FMU anomaly All mechanism commands have been adjusted • New OMI anomaly for outer swath last year • Another comparable OMI anomaly recently on around row 40 swath position For last 2 anomalies : OMI flight model - level 1 and 2 data are affected - potential cause is identified, but difficult to confirm - possibility correction mechanism is investigated See Dobber’s presentation today Prof. Dr. P. F. Levelt, KNMI, TUE, June 11, 2008, NIVR and tomorrow

Collection 3 Processing Summary Prof. Dr. P. F. Levelt, KNMI, TUE, June 11, 2008, NIVR

Validation Status COL 3 Data Product Released Level 1 B Public Total Column Ozone (TOMS) Public Total Column Ozone (DOAS) Public Aerosol (NASA – AI AOT AAOT) Public Aerosol (KNMI – AOD SSA) Public Nitrogen Dioxide Total Column Public Nitrogen Dioxide tropospheric column Public Cloud Height and Fraction O 2 -O 2 Public Cloud Height and Fraction Raman Public Surface-UV Public Sulphur Dioxide (STL TRM PBL) Public Formaldehyde Public Bromine Oxide Public Chlorine Dioxide Public Status Ozone Profile Provisional Prof. Dr. P. F. Levelt, KNMI, TUE, June 11, 2008, NIVR Validated and Good for Science Validated and Some Problems Validated but Use with Caution Validation Preliminary Not Publicly Available

OMI – MLS Ozone Profiles Preliminary results for OMI vs MLS ozone profiles Prof. Dr. P. F. Levelt, KNMI, TUE, June 11, 2008, NIVR Distance < 100 km Same orbit

Status of OMI Data Products (collection 3) Product Provisional release Validated Stage 1 release (Public) - Level 1 B Released KNMI Released NASA GSFC Released KNMI - Total Column Ozone Released KNMI OMI website: (TOMS) (http: //www. knmi. nl/omi) - Total Column Ozone Released Algorithm originator (DOAS) - Aerosol (UV and multi-l) Released NASA GSFC & KNMI - Cloud Height (O 2 -O 2) Released KNMI - Surface UVB Released FMI & NASA GSFC - HCHO Released Harvard Instrument and level 0 -1 b Released data processing Released overview: - NO 2 total and trop. KNMI & NASA GSFC (http: //www. knmi. nl/omi/research/calibration/instrument_overview) column Data: NASA (Raman)DISC (http: //disc. gsfc. nasa. gov/Aura/OMI) GSFC - Cloud Height Released NASA NRT data: TEMIS website (http: //www. temis. nl) - SO Released VFD 2 data : Very Fast Delivery (http: //omivfd. fmi. fi) - Br. O Released NASA GSFC Harvard IEEE Aura special Issue: instrument, algorithm Released results. Harvard and first papers - OCl. O Released (March 2006) - O 3 Profile Released Not released KNMI JGR special issue: validation papers (2008) Prof. Dr. P. F. Levelt, KNMI, TUE, June 11, 2008, NIVR

This meeting Main Topics: • AQ and Climate session • Validation session • OMI anomaly • Blue team review and preparation for review in November for Aura extension: • Mark and Anne will come Wednesday • Future missions: TROPOMI Prof. Dr. P. F. Levelt, KNMI, TUE, June 11, 2008, NIVR

Back up Prof. Dr. P. F. Levelt, KNMI, TUE, June 11, 2008, NIVR

Spatial Resolution OMI Zoom 12 x 13 km 2 OMI 24 x 13 km 2 Mexico City January 20, 2005 Prof. Dr. P. F. Levelt, KNMI, TUE, June 11, 2008, NIVR Approx. GOME-2 72 x 39 km 2

Detection Limit Test • Assume two areas with different yearly average NO 2 concentrations; • Simulate the measured NO 2 assuming a variation of 100% and a cloud contamination of 50%; • Sample the simulated NO 2 with a sensor with a certain spatial and temporal sampling and measurement uncertainty; • Using a statistical test at 67 and 95% confidence level, determine the minimum detectable difference. Prof. Dr. P. F. Levelt, KNMI, TUE, June 11, 2008, NIVR

Ozone Monitoring Instrument OMI • UV and VIS backscatter instrument (270 - 500 nm) • Wide swath telescope yields daily global maps (2600 km) • Urban scale resolution is best ever for air quality measurements from space (13 x 24 km 2) Heritage: GOME, SCIAMACHY, GOMOS and TOMS Prof. Dr. P. F. Levelt, KNMI, TUE, June 11, 2008, NIVR

First comparisons of MODIS & OMI cloud pressures: Hurricane Katrina (Joiner et al. , GRL, 2006) Some differences expected; Cloudsat data not available at the time. Spiral structure seen in OMI cloud pressures, but not in MODIS cloud-top pressure. Hypothesis: UV radiation penetrates deep inside a cloud because OMI UV channels see through high thin cirrus to lower water clouds with band structure. Prof. Dr. P. F. Levelt, KNMI, TUE, June 11, 2008, NIVR

Instrument and calibration status • OMI operations 99 % • Calibration daily OPF updates for dark current corrections: Collection 3 Anomalies OMI: • FMU anomaly All OMI commands have been adjusted • New OMI anomaly for outer swath last year • Another comparable OMI anomaly recently on around row 40 swath position For last 2 anomalies : - level 1 and 2 data are affected - potential cause is identified, but difficult to confirm - possibility correction mechanism is investigated See Dobber’s presentation today and tomorrow Prof. Dr. P. F. Levelt, KNMI, TUE, June 11, 2008, NIVR OMI flight model