TROPOMI on Sentinel 5P the next generation atmospheric composition spectrometer

Transcription

1 TROPOMI on Sentinel 5P the next generation atmospheric composition spectrometer J.P. Veefkind*, I. Aben and P.F. Levelt

2 sentinel-5 precursor GMES ATMOSPHERE MISSION IN POLAR ORBIT The ESA Sentinel-5 Precursor (S-5P) is a pre-operational mission focussing on global observations of the atmospheric composition for air quality and climate. The TROPOspheric Monitoring Instrument (TROPOMI) is the payload of the S-5P mission and is jointly developed by The Netherlands and ESA. The planned launch date for S-5P is 2015 with a 7 year design lifetime. TROPOMI UV-VIS-NIR-SWIR nadir view grating spectrometer. Spectral range: , , nm Spectral Resolution: nm Spatial Resolution: 7x7km 2 Global daily coverage at 13:30 local solar time. CONTRIBUTION TO GMES Total column O3, NO 2, CO, SO 2,CH 4, CH 2 O,H 2 O,BrO Tropospheric column O 3, NO 2 O 3 profile Aerosol absorbing index, type, optical depth

3 TROPOMI Science Objectives To better constrain the strength, evolution, and spatiotemporal variability of the sources of trace gases and aerosols impacting air quality and climate. To improve upon the attribution of climate forcing by a better understanding of the processes controlling the lifetime and distribution of methane, tropospheric ozone, and aerosols. To better estimate long-term trends in the troposphere related to air quality and climate from the regional to the global scale. To develop and improve air quality model processes and data assimilation in support of operational services including air quality forecasting and protocol monitoring.

4 OMI-TROPOMI-Sentinels

5 daily global coverage sentinel-5 precursor GMES LOW EARTH ORBIT ATMOSPHERE MISSION ~2030 hourly over Europe sentinel-4 GMES GEOSTATIONARY ATMOSPHERIC MISSION

6 Validation KNMI, SRON, ESA,... Principal Investigator KNMI (PI), SRON (co-pi) Level 1-2 KNMI, SRON, DLR, IUP BIRA-IASB, MPI Mainz, RAL Level 0-1B KNMI Ground Segment DLR Operations KNMI, ESOC Calibration KNMI / SRON Dutch Space / TNO Instrument prime Dutch Space

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8 TROPOMI Spectral Bands Spectrometer UV UVIS NIR SWIR Band ID Spectral range [nm] Spectral resolution [nm] Spectral sampling [nm] <0.1 Spatial sampling [km 2 ] 21 x 28 7 x 7 7 x 7 7 x 7 7 x 7 7 x 1.8 7x7 Detector binning factor Minimum Signal-to-noise 100 (1 ( ( ( (2 across track (swath) wavelengths Flight direction ~7 km (1 s flight) ~2600 km

9 UV UVN-OBM Mass ~200 kg Average power ~150W Level 1B size is approx. 20 GByte /orbit: 25x data volume of OMI SWIR-OBM Telescope UVIS Nadir Baffle Connector Bracket Sun Baffle Telescope Support Structure Diffuser mechanism Folding Mirror mechanism

10 Suomi-NPP - S5P formation Flying S-5P is planned to observe within 5 min. of Suomi-NPP. Primary goal is to use VIIRS cloud mask for S-5P methane observations. Other opportunities: TROPOMI-VIIRS cloud and aerosol combined products. TROPOMI-OMPS-CRIS ozone profiles. TROPOMI-OMPS intercalibration.

11 TROPOMI Data Products Product Ozone total column profile (incl. troposphere) trop. column NO2 total column trop. column Accuracy :: Precision 3% :: 1% 10% :: 5% 25% :: 10% mol/cm 2 10% :: mol/cm 2 CO total column 15% :: 10% CH4 total column 2% :: 1% SO2 volcanic plume top. column Aerosol AAI aerosol layer height* aerosol optical thickness single scattering albedo Cloud radiance fraction pressure mask Regridded VIIRS 2 DU :: 1 DU 1 DU :: 0.5 DU n/a :: km :: 0.5 km 0.1 (20%) :: 0.05 (10%) 0.05 :: :: hpa :: 20 hpa Product CH2O total column CHO-CHO total column BrO total column HDO total column Accuracy :: Precision TBD TBD TBD TBD H2O total column 20% :: 10% OClO total column UV surface flux TBD 10% :: 5% Surface Reflectance monthly climatology 3% :: 1% The operational data products will be developed by a collaboration of European institutes. KNMI/DLR-IMF/IUP/BIRA-IASB/SRON/MPIC/RAL

12 From OMI to TROPOMI 6x higher spatial resolution 7x7 km 2 vs. 13x24 km 2 1-5x higher signal-tonoise better cloud information from the oxygen A band CO and CH 4 observations from the SWIR band Gloudemans et al., SCIAMACHY CO over land and oceans: interannual variability, ACP, 2009

13 High Spatial Resolution From Valin et al., AMT, 2011

14 TROPOMI air quality climate ozone layer Scientific Appl process studies trend studies... Operational Appl air quality uv index aviation safety Assessments air quality ozone climate Near-Real-Time Offline

15 TROPOMI Data Product Development Goal: To develop operational TROPOMI data products that meet the user requirements are state-of-science have reliable and well-described quality have open access and are easy to use contribute to long-term data records are continuously evaluated and improved are of reasonable quality within 3 (tbc) months after commissioning

16 AOT-HCHO: Summer Anomalies JJA AOT JJA AOT Anomaly JJA NO2 Anomaly JJA HCHO Anomaly Veefkind et al., ACP, 2011 Years

17 Summary & Outlook The research with OMI and related missions is making important steps from qualitative to quantitative information. The ESA/EU Sentinel program will continue the OMI/GOME/SCIAMACHY data records until The Sentinel 5 Precursor with its payload TROPOMI is planned for launch in TROPOMI will be a major step forward for atmospheric composition observations due to improved spatial resolution & sensitivity. AOT HCHO NO2 SO2

18 Contents lists available at SciVerse ScienceDirect Remote Sensing of Environment journal homepage: TROPOMI on the ESA Sentinel-5 Precursor: A GMES mission for global observations of the atmospheric composition for climate, air quality and ozone layer applications J.P. Veefkind a,g,, I. Aben b, K. McMullan c, H. Förster d, J. de Vries e, G. Otter f, J. Claas a, H.J. Eskes a, J.F. de Haan a, Q. Kleipool a, M. van Weele a, O. Hasekamp b, R. Hoogeveen b, J. Landgraf b, R. Snel b, P. Tol b, P. Ingmann c, R. Voors e, B. Kruizinga f, R. Vink f, H. Visser f, P.F. Levelt a,g

19 Ozone Monitoring Instrument Ozone Monitoring Instrument Instrument Spectral Range Spectral Resolution Spectral Sampling Spatial Resolution Swath Width Mass Size Power Data rate Spacecraft Imaging spectrometer nm nm nm 13x24 km 2 (nadir) 2600 km 65 kg 50 cm 40 cm 35 cm 66 W 0.8 Mbps (average) NASA EOS-Aura Launch Date 15 July 2004 Orbit Altitude Agencies PI Institutes Sun synchronous, 13:30 hr 705 km NSO (NIVR), FMI KNMI, FMI OMI is the Dutch-Finnish contribution to the NASA EOS-Aura Mission and is developed by an international consortium led by Dutch Space and TNO.

20 Temporal Co-Reg for TROPOMI/VIIRS To use VIIRS data for cloudclearing TROPOMI data the time difference should be less than 1-7 min, depending on cloudcleared area. (Genkova et al., AMTD) A B C Data sets: MSG SEVIRI cloud mask with 15 min interval for 2006 over Europe, GOES-10 1 minute interval data for 23 August 2006 over the South U.S.A. Cases studied: A) cloud cleared region 18x9 km 2, B) 30x15 km 2, C) 30x27 km 2. Center pixel coincides with the target S-5 pixel.

21 OMI NO2 over Europe, Oct May Close to land, continental emissions hinder the detection of shipping NO2 (left). When only data acquired under conditions of low windspeed (<= 2 Bft.) are used, shipping features become more clear (right). For example, the highest value over water is then found exactly over the Street of Dover, the busiest shipping lane in the world. M. de Ruyter de Wildt, TUE

22 OMI Lessons Learned 1. OMI successfully demonstrates the use of 2-D detectors for nadirviewing solar backscatter spectrometers. 2. The optical degradation is the lowest of UV instruments launched. 3. The wide angle telescope, the polarization scrambler and the QVD solar diffusor were all successful. 4. Unique on-ground calibration measurements (i.e. stray light measurement) have to be measured at various angles and for inflight representative conditions. 5. Measurement of the instrument spectral response (slit) function was successfully performed and has preference over gas cell measurements. 6. Effects of detector degradation (RTS effects) should be decreased by frequently updating dark current maps and lowering the detector temperature. 7. Solar irradiance measurements and other calibration measurements should have a SNR much higher than the radiance data to avoid stripes in the data products.

23 SE USA: Seasonal Variations Spatial-temporal correlation between AOT and formaldehyde. Formaldehyde is produced from biogenic isoprene sources. AOT signal of ~0.2 than models predict. [e.g. van Donkelaar et al., AE, 2007]