Jolyon Reburn Remote-Sensing Group Earth Observation and Atmospheric Science Division, SSTD

1. CAPACITYOperational Atmospheric Chemistry Monitoring MissionsESA contract no. AO/1-4273/02/NL/GSAssessment of Existing and Planned Space Missionsand Ground NetworksFinal PresentationESTEC, Noordwijk2 June 2005 Jolyon Reburn Remote-Sensing Group Earth Observation and Atmospheric Science Division, SSTD Rutherford Appleton Laboratory

2. Content Assessment of Existing and Planned Space Missions and Ground Networks • Consortium • Outline and Context • Space Programmes for Atmospheric Sounding • Assessment of Instruments • Observation Techniques • Instrument Data • Analysis Method • Capabilities and Limitations of MetOp/NPOESS & other Planned Missions • Summary and Conclusions CAPACITY Final Presentation

3. Instrument Consortium Co-ordinator J.Reburn, RAL Ground-based Networks trace gases M. de Maziere, BIRA aerosol F-M. Breon, LSCE Satellite Obervations nadir-uv/vis/nir/swir H. Bovensmann, M. Weber, IUP R. Jongma, I. Aben, A. Maurellis, SRON; R. Siddans, RAL passive nadir aerosolF-M. Breon LSCE, C. Poulsen RAL nadir-mir C. Clerbaux CNRS lidar F-M. Breon LSCE limb-mm/sub-mm N. Lautie, RSS; C. Verdes, IFE; V.Jay, RAL limb-mir G. Stiller, IMK; J. Remedios, UL limb-uv/vis/nir/swir H. Bovensmann, C v Savigny, IUP occultation C. Clerbaux, CNRS; H. Bovensmann, IUP CAPACITY Final Presentation

4. Outline and Context The task was to examine and assess the capabilities of existing and planned : • Space Missions • Ground-based Networks To set the context for the space-borne elements a review of future programmes, relevant to atmospheric sounding, by European and other national agencies was also carried out. CAPACITY Final Presentation

5. Outline and Context • The “Instrument Team” provided instrument performance data • The capabilities of instruments were assessed quantitatively against requirements Note: The data requirements in this study are defined for longer term “monitoring” purposes • In this context the operational satellite observing system, comprising the European MetOp and the American NPOESS missions, is the foundation, and therefore merits particular attention. CAPACITY Final Presentation

6. Space Programmes CAPACITY Final Presentation

7. Space Programmes • Space agencies are continually developing new programmes including both • research missions (e.g. ESA, NASA) • operational missions (e.g. EUMETSAT, NOAA) • In the context of this study, the latter are more relevant, although research programmes will also contribute to atmospheric monitoring CAPACITY Final Presentation

8. Space Programmes • ESA/EU GMES Sentinel Programme • CAPACITY study directed to this • EUMETSAT post-MSG and -EPS Programmes • ESA Explorer Programme • 6 approved missions • NASA ESSP • follow on from EOS Aqua, Terra, Aura • NPOESS (US) • NPP + 6 operational systems • Other National Agencies e.g. JAXA (Japan) CAPACITY Final Presentation

9. Assessment of Instruments CAPACITY Final Presentation

10. Observation Techniques • Ground Networks • trace gases (O3 sondes, photometers, chromatographs …) • aerosol (spectral radiometers …) • Satellite Observations • nadir-uv/vis/nir/swir • passive nadir-sounding of aerosol • nadir-mir • lidar • limb-mm/sub-mm • limb-mir • limb-uv/vis/nir/swir • occultation CAPACITY Final Presentation

11. Instrument Data The “Instrument Team” provided • instrument descriptions • performance data (where available) and references Performance data was collected for products that are or are likely to be produced routinely The data included: • Horizontal resolution, horizontal sampling • Temporal sampling / revisit time • Profile of vertical resolution and uncertainty • Author and source reference CAPACITY Final Presentation

12. Instrument Data Approach: • For the ground network and current satellite missions, standard demonstrated sensor performances were used • For future satellite missions they were estimated from contemporary missions and retrieval simulations supplied to the study team from other projects CAPACITY Final Presentation

13. Analysis Method • Instrument capabilities analysed for all 9 user application areas in tables which directly mirror the Data Requirement Tables • Analyses vs. requirements were carried out for • Each instrument • By individual applications • By theme (Ozone, Air Quality, Climate) • Satellite missions, comprising several instruments • 9 application areas → ~130 product requirements → >35 instruments → 264 pages of tables CAPACITY Final Presentation

14. Analysis Method CAPACITY Final Presentation

15. Analysis Method CAPACITY Final Presentation

16. Analysis Method • Requirements met partially • capability matches the least demanding requirement (also referred to as threshold) • Requirements met fully • means that the most stringent requirement (or target) is met (NOTE: requirements and capabilities given as ranges so different levels of agreement possible) CAPACITY Final Presentation

17. Analysis Method CAPACITY Final Presentation

18. Capabilities & Limitations of MetOp/NPOESSand other Planned Missions CAPACITY Final Presentation

19. Capabilities of MetOp/NPOESS & other planned missions CAPACITY Final Presentation

20. Capabilities of MetOp/NPOESS & other planned missions Water Vapour • MetOp/NPOESS sounding adequate in lower trop. • Will not provide useful H2O data above tropopause and vertical resolution in upper troposphere will not be sufficient for some applications Aerosol & Cloud • Imagers in polar and geo orbit will provide geographical coverage, aerosol optical thickness, size and other parameters. • APS on NPOESS will deliver additional aerosol parameters (e.g. ref. index, single scatter alb.) along track • Active instruments will provide tropospheric vertical profiles, although design lifetimes are relatively short CAPACITY Final Presentation

21. Capabilities of MetOp/NPOESS & other planned missions Ozone • MetOp/NPOESS will provide observations to monitor stratospheric and total column O3 • Tropospheric O3 retrieval, demonstrated for GOME-1. Simulations indicate improvement possible from addition of IASI/CrIS (FTIR) to GOME-2/OMPS (uv) • The operational system will provide uv/vis observations at 2 local times: ~09:30 (GOME-2), ~13:30 (OMPS) CAPACITY Final Presentation

22. Capabilities of MetOp/NPOESS & other planned missions Carbon Dioxide • The FTIR spectrometers on MetOp, NPOESS and GOSAT will also observe CO2, and the near-IR grating spectrometer on OCO is designed specifically to do so • Whether these observations will meet the stringent requirements defined in CAPACITY is TBD CAPACITY Final Presentation

23. Capabilities of MetOp/NPOESS & other planned missions Trace gases other than H2O, O3 and CO2 • MetOp and NPOESS uv/vis sensors: • trace gas total columns will be derivedi.e. NO2, SO2, H2CO and BrO • stratospheric limb-observations by OMPS may also offer BrO and NO2 information • The operational system will provide uv/vis observations at only two local times (9:30am for GOME-2 and 13:30 for OMPS) CAPACITY Final Presentation

24. Capabilities of MetOp/NPOESS & other planned missions • MetOp and NPOESS FTIR sensors: • several trace gases in addition to H2O and O3 will be measured e.g. CH4 and CO • height-assignment/resolution intrinsically limited • sensitivity lowest in boundary-layer (except H2O), because T contrast with surface is lowest • Sensors will operate concurrently in (at least) two orbits, so observations will be made at four local times per day (equator crossing times: 01:30, 09:30, 13:30 and 21:30) • Given the photochemical lifetimes of CH4 and CO, non-compliance on temporal sampling less critical than for short-lived pollutants measured in uv/vis CAPACITY Final Presentation

25. Limitations of MetOp/NPOESS & other planned missions CAPACITY Final Presentation

26. Ground-based Networks • The ground-based networks provide measurements of many of the required products and uncertainty and time-sampling/revisit requirements are met in most cases. • The capabilities of these networks is likely to continue to play an important part in monitoring the atmosphere. • It is, however, clear from the assessment that there is, in general, a lack of altitude attribution and that some height ranges are not well addressed. • In many cases only surface, partial column or low-vertical-resolution profiles are provided, whereas high-vertical-resolution profiles are often specified in the requirements. • It should be noted that aerosols, particulates, tracers and some organic compounds are not appropriately addressed for several applications. CAPACITY Final Presentation

27. Summary & Conclusions CAPACITY Final Presentation

28. Summary & Conclusions • The ground network, current satellite missions and new satellite missions planned for 2010-2020 were reviewed to evaluate their contributions to monitoring of atmospheric composition. • The review confirmed that the ground networks and satellite missions planned for 2010-2020 would make valuable contributions to atmospheric composition monitoring in that period. • However, the review also identified a number of limitations which can be summarised as follows: CAPACITY Final Presentation

29. Summary & Conclusions • Spatio-temporal sampling of the boundary layer by MetOp and NPOESS is too sparse to comply with the stringent requirements for air quality applications. It is limited by two factors: 1. ground-pixel size determines how frequently observations can be made between clouds 2. equator crossing times observations of O3 and short-lived pollutants NO2, H2CO and SO2 will be made at ~9:30am (GOME- 2 and ~1:30pm (OMPS), but not later in the day, which would be: (a) necessary for attribution of afternoon pollution episodes and (b) closer to early morning air quality forecast time CAPACITY Final Presentation

30. Summary & Conclusions • Spectral coverage needed at swir wavelengths, i.e. longer than GOME-2 and OMPS, to: • improve MetOp/NPOESS sensitivity to CH4(and CO) in the boundary layer and • resolve tropospheric aerosol into several layers – needed for climate and air quality applications • To target tropospheric trace gases (e.g. non-methane hydrocarbons) additional to those measured by IASI and CrIS, a nadir mid-infrared (FTIR) instrument with higher spectral resolution would be needed, i.e. similar to TES. CAPACITY Final Presentation

31. Summary & Conclusions • Requirements for sounding trace gases and aerosol in the upper troposphere and stratosphere will not be addressed at all by MetOP or NPOESS, except for: • stratospheric O3 (GOME-2 & OMPS) • stratospheric aerosol (OMPS) • (possibly) stratospheric NO2 and BrO (OMPS) • These requirements are currently being addressed by the Odin, Envisat and Aura limb-sounders, but none of these are likely to still be functioning beyond 2010. CAPACITY Final Presentation

32. Summary & Conclusions • No UV-VIS or IR solar occultation sensors for long-term monitoring of stratospheric trace gas and aerosol profiles are currently planned after MAESTRO and ACE on SCISAT, which are unlikely to still be functioning beyond 2010. • The vertical resolution of ground based sensors is not sufficient in a number of cases to meet requirements placed on them for profile measurements.(It should be noted that sensors on airborne platforms may meet the vertical resolution requirements in some height ranges, but these have not been examined quantitatively in this study.) CAPACITY Final Presentation

33. Thank you CAPACITY Final Presentation