1. August 19, 20081 NASA Mission Concept Studies for GEO-CAPE S. R. Kawa, S. Janz, R. T. Caffrey, A. Mannino, E. Middleton, L. Purves, S. Bidwell (NASA Goddard Space Flight Center) J. Fishman, D. Neil (NASA Langley Research Center) Study Process and Objectives Atmospheres: Science, Measurements, Instruments + Coastal Ocean: Science, Measurements, Instrument Mission and Payload Concept Summary

2. 2 Overview of Study Process HQ-commissioned Mission Studies (8 primary + 5 combined): –August 2006 to February 2007 –Motivation: prepare for recommendations of Decadal Survey –Objectives: identify science requirements, develop instrument and mission concepts, examine cost versus performance –Science working group, instrument synthesis lab, and integrated mission design studies for each –Products: design studies and summary reports

3. 3 Relevant Mission Studies 1) Geostationary Multi-spectral Atmospheric Composition (GeoMAC): atmospheric chemistry mission only, similar to GEO-CAPE atmospheres a) moderate resolution scanning UV-Vis spectrometer (GSFC ISAL) b) CO imager in solar infrared and thermal emission (LaRC IDC) c) Imaging Fabry-Perot detector for near-surface O 3 (IIP)  $850M 2) Integrated Mission #5/Geostationary Multi-discipline Observatory (GMO): combines objectives of GeoMAC with coastal ocean (and terrestrial biosphere), corresponds closely to GEO-CAPE a) and b) as above c) very high-spatial resolution event imaging UV-Vis spectrometer (GSFC ISAL)  $1268M

4. 4 Science Overview: Local Emissions/Global Impact Tropospheric O 3 from OMI and MLS (June ‘05 avg) [Ziemke et al., 2006]  Local and regional emissions impact ozone and aerosol on local to global scales.  Global changes in ozone, aerosol, and other pollutant species impact climate change and affect local air quality.  Better understanding of the key processes that connect global and local scales is required to accurately simulate, assess, and project these effects in the future.  GEO-CAPE is a mission to investigate the basic science of atmospheric composition and transport processes that underlie our ability to forecast air quality.

5. 5 Elements of The (Atmospheric) Science Question 1. What are the emission patterns of the precursor chemicals for tropospheric ozone and aerosols? 1. Quantify spatial and temporal emissions of ozone and aerosol precursors (NO x, CO, hydrocarbons, SO 2, particle emissions). 2. What is the evolution of ozone and aerosol through chemical formation and loss, transport, and deposition processes? 2. Measure distributions of ozone, aerosol, and precursors at high spatial and temporal resolution over the US and surrounding regions. 3. What are the influences of weather in transforming and dispersing emissions, ozone, and aerosol? 3. Track transport of aerosol and gases into, across, and out of NA; including large episodic releases from environmental disasters, e.g., fires, volcanoes. 4. What are the regional budgets for air quality criteria pollutants (CO, O 3, NO 2, SO 2, and aerosol) over North America? 4. Characterize regional air quality for model evaluation, assessment, and forecasting. Mission Science Questions  Mission Science Objectives

6. 6 Why Geostationary Orbit: Temporal Resolution  Low earth orbit (LEO/sun sync) affords at best one sample per day at a given location in mid latitudes. Key processes occur on relatively short time scales that are not accessible from LEO observations. O3O3 SO 2 CO NO 2 Local Time (hr) [Bovensman et al., 2003] NO 2 Surface NO 2 (ppb) Column NO 2 (10 15 mol. cm -2 ) OMI Column Measurements Day 1Day 2 June 22 Hour of Day (GMT) June 23 CMAQ Model Simulation of NO 2  Target continuous hourly sampling of key constituents

7. 7 Why Geostationary Orbit: Coverage and Spatial Resolution  Coverage: Once per day samples often obscured by clouds.  Spatial Resolution: - longer Geo time integration allows high SNR/ resolution element - higher spatial resolution improves chance of cloud-free pixel  Target 5 to 7-km pixel resolution over continental field of view. Consistent with that anticipated for regional chemistry/transport models in the next decade. Enable boundary layer O 3 determination through cloud slicing Potential to transform our understanding of atmospheric composition similar to the way GOES imagery has advanced weather analysis and forecasting. Tropospheric NO 2 from OMI for June 6, 2005 [Bucsela et al., 2006] CO (ppbv) from MOPITT (June 21, 2005)

8. 8 Science Traceability Matrix for Atmospheres Mission ObjectivesMeasurement Requirements Mission Requirements Instrument Requirements Mission ConceptAncillary Requirements Quantify spatial and temporal emissions of ozone and aerosol precursors NO 2 and HCHO tropospheric partial column, CO with sensitivity in the boundary layer (BL) Cover US and adjoining regions Simultaneous constituent measurements Continuous daytime coverage High spatial resolution (5 km) to resolve source locations and sample between clouds; high precision detection (SNR>1000:1) CO measurement in reflected sunlight Instruments in geo orbit continuously scan populous N America coast-to-coast. UV/Visible spectrometer measures O 3, NO 2, HCHO, SO 2, and aerosol column density; plus CO, O 3 detectors for BL and free trop Surface in situ and remote sensing monitoring network; in situ aircraft and balloon mmts; stratospheric O 3, NO 2, and dynamics Inverse models for source inference. Measure distributions of O 3, aerosol, and precursors at high spatial and temporal resolution over the US and surrounding regions. O 3 partial column; O 3 with sensitivity in PBL; aerosol optical depth Measure diurnal changes of constituents Map sunlit earth at near-nadir Hourly sampling frequency in polluted regions View upwind and downwind of the continent Day/night CO and O 3 sampling Spectrally resolved, high-SNR reflected UV/Vis radiances O 3 measurement in thermal emission bands (and/or reflected sunlight) CO measurement in thermal emission bands Ability to stare at target region from geo enables high-resolution ground sampling at high SNR. Hourly or better sampling frequency during daytime for UV/Vis, and during day and night for free- troposphere CO and O 3. GOES T, H 2 O profiles, surface, and upper-air weather observations; accurate, detailed meteorological analyses 3-D global chemistry- transport model integrations Process-oriented research field campaigns Track transport of aerosol and gases into, across, and out of NA; including large episodic releases from environmental disasters CO in mid-troposphere; O 3, NO 2 tropospheric partial columns; aerosol optical depth, SO 2 column density Characterize regional air quality for model evaluation, assessment, and forecasting. O 3, NO 2, HCHO, CO partial columns; O 3 with sensitivity in PBL; aerosol optical depth Accommodate large data collection and retrieval rates; 2-5 yr mission lifetime Continental field of regard; hourly temporal resolution in polluted regions High-resolution, frequent sampling maximizes lower troposphere data in presence of clouds Data assimilation methodology; Regional mesoscale chemistry-transport modeling

9. Goddard Space Flight Center 9 Instrument Suite Concept 1.UV/Vis - Scanning UV/Visible spectrometer (300 – 480 nm); detect total column O 3, NO 2, HCHO, SO 2, and aerosol; limited efficiency for O 3 in the boundary layer. 2.CO Detector - Gas correlation filter radiometer measuring in reflected near-IR and thermal IR emission; senses atmospheric CO total column to surface and mid- and upper-troposphere weighted; separate boundary layer from free troposphere abundance. 3.Trop O 3 - Imaging Fabry-Perot spectrometer for O 3 in the thermal IR; sensitivity decreases near the surface more slowly than UV/Vis; determination of near-surface O 3 in combination with UV/Vis.  Measurements all need to be made closely in time and space to enable detailed examination of transport and photochemical processes, e.g., O 3 production from CO oxidation: CO + OH + O 2  CO 2 + HO 2 HO 2 + NO  OH + NO 2 NO 2 + h + O 2  NO + O 3 Diurnal process studies Increasing Tropospheric return GeoMAC OMI TOMS GOME TES MOPITT

10. Goddard Space Flight Center 10 Measurement Requirements and Instrument Suite Trace GasNeeded mixing ratio precision Needed accuracy Column density capability* [molecules cm -2 ] Instrument Requirement [SNR] Instrument Implementation NO 2 0.2 ppbv  20% 5.0 x 10 14 2000 (430 nm)UV/VIS grating spectrograph: Cost effective broadband measurement at moderate spectral resolution (< 1nm). High spectral stability and throughput. Strong heritage. HCHO1.0 ppbv  20% 2.5 x 10 15 1500 (350 nm) O3O3 10 ppbv (troposphere)  10% 1.3 x 10 16 1000 (320 nm) SO 2 Not applicable  20% 2.2 x 10 16 500 (312 nm) O3O3 10 ppbv (troposphere)  10% 1.3 x 10 16 100 ( 9.6  m) Fabry Perot Interferometer: Successful IIP. CO10 ppbv  10% 1.0 x 10 17 2500- 9500 ( 2.3  m) (scene dependent) Gas Filter Correlation Radiometer: Target gases with very high sensitivity/resolution. Multi-spectral for robust retrieval and to separate PBL from free trop. Strong heritage. CO10 ppbv  10% 1.0 x 10 17 700 (4.67  m) Near- surface CO 10 ppbv  10% 1.0 x 10 17 Not applicableInferred from multispectral analysis Near- surface O 3 5 ppbv  10% 1.3 x 10 16 Not applicableInferred from multispectral analysis Trace gas sensitivity required to meet science goals * Assumes PBL height of 1 km. Additional information on science requirements can be found at http://qp.nas.edu/QuickPlace/decadalsurvey/Main.nsf

11. 11 Measurement demonstration and technical feasibility completed under NASA Instrument Incubator Program. No technical hurdles to instrument or spacecraft. Pointing requirements are commensurate with GOES. Detector optimization, single crystal silicon mirror testing, and aircraft demo recommended for technology readiness level 6. Performance DataTechnology Assessment / Development Needs Measure atmospheric pollutants O 3, aerosols, and precursors NO 2, SO 2, HCHO. Field of regard: Western Hemisphere with emphasis on continental United State Sample revisit time of 1 hour, during sun illumination. Mission Design Life: 2 years, goal 5 years (consumables sized for 5 years), launch Sept. 2014. Measurement Concept Star Tracker (1 of 2) Calibration Assembly / Calibration Aperture Optical Bench Optics Aperture and Scanning Mirror Gyroscopes Thermal Radiator 1700 mm 860 mm 830 mm From ISAL Single focal plane, continuous band from 300 nm to 480 nm. Spectral resolution: 0.8 nm. Signal-to-noise ratio of 720 at 320 nm and 1500 at 430 nm. Typical scanned field-of-view: 8° N/S (5000km) x 8° E/W (5000 km). Can point anywhere on visible hemisphere. Pointing stability maintained through active jitter compensation. Sample spatial resolution 1.25 km N/S x 5.0 km E/W. Scanning UV/Vis Spectrometer

12. 12 Carbon Monoxide Detector Instrument Performance Data Technology Assessment / Development Needs Measurement Concept Gas correlation filter radiometer measures CO in near-IR reflected sunlight and thermal IR emission. Spectral combination approach identifies CO boundary layer distribution from space. Measures CO, an atmospheric pollutant precursor of O 3 and primary indicator of combustion. Continue outstanding performance of MOPITT; scientific findings based on MOPITT data demonstrate the measurement maturity and technical feasibility. Detector: Use of large format 2-D arrays in space (no scanning) Data array: 1024 x 1024 pixels for each SWIR & MWIR Spatial resolution: 5 x 5 km 2 ; spectral resolution better than 0.1 cm -1 provided by gas filter. Each spatial pixel requires frame averages to achieve SNR. Onboard calibration: blackbody targets, deep space and solar views Technology for this instrument is at high readiness level. Measurement Heritage: MOPITT, HALOE Beneficial investments: - Radiation hard high performance electronics - Light weight thermal control and structural materials Dimensions: 1.31 x 0.55 x 0.43 m From LaRC IDC

13. 13 Multi-discipline Science Questions What are the effects of gaseous and particulate emissions and climate variability and change on global atmospheric composition, and how will future changes in atmospheric composition affect ozone, climate, and regional/global air quality? How are coastal ocean ecosystems and the biodiversity they support influenced by climate or environmental variability and change, and how will these changes occur over time? What is the current geographical distribution, composition, and health of the terrestrial biosphere around the world, and how are its component ecosystems responding to climate changes? (from Strategic Plan, Sub-Goal 3A: 3A.1: Progress in understanding and improving predictive capability for changes in the ozone layer, climate forcing, and air quality associated with changes in atmospheric composition; 3A.3: Progress in quantifying global land cover change and terrestrial and marine productivity, and in improving carbon cycle and ecosystem models [NASA 2006]).

14. 14 Coastal Ocean Spatial Resolution Sample coastal waters at 300-m resolution 250 x 500 km scan/15 min Measurement Objective: Ecosystem carbon, physiology and functional type with event scale multiple observations per day.

15. 15 Ocean Ecological Products Critical products: Primary productivity, chlorophyll, particulate organic carbon, dissolved organic carbon (DOC), colored dissolved organic matter (CDOM), fluorescence line height, calcite, phytoplankton physiology and functional type (including harmful algal blooms). DOCCDOM(355)Chlorophyll A2006132

16. Goddard Space Flight Center 16 What is the current distribution and species or functional type composition of the major forest and grassland ecosystems and agricultural systems? What is the status of disturbance and fragmentation in these systems? What is the temporal variation in biogeochemical processes (e.g., transpiration, light use efficiency, nutrient uptake) that affect productivity in these ecosystems? How are terrestrial ecosystems affected by and responding to climate variability and change? Elements of the Science Question for Terrestrial Biosphere

17. 17 Imaging Spectroscopy for Terrestrial Biosphere

18. 18 Observatory Concept  Combine instrumentation to enable coastal ocean and terrestrial biosphere science and enhance atmospheric science. Combination of medium- resolution (5 km) continental scanning instruments with high-resolution (300-m) regional viewing spectrometer. Very high spatial resolution, programmable geosynchronous multi- disciplinary observatory. Shared resource for regular observations, special observing studies, and emergencies Precursor designs in ESEI, COCOA, GEOCarb. Meet or exceed discipline science measurement requirements. Potential ground-breaking new science in each discipline plus synergies. Washington, DC imaged with 5-km pixels. Continuous scan of polluted regions Programmable high-resolution observations

19. 19 Multi-discipline Instrument Requirements Coastal OceanAtmosphereBiosphere Spectral Bands (nm) 340-1100, 1240, 1640300-480, 400-600, 2300, 4600 400-1300, 2000-2300 SNR>1000 in UV-VIS1000>800 Spectral Resolution1-5 nm<1 nm UV 1-2 nm Vis 5-10 nm Spatial Resolution100-300 m>1 km<250 m Temporal Resolution3-6 / day~ hourly3-6 / day Spatial Coverage ~320 km Ocean adjacent to coast; estuaries, bays, rivers, large lakes 200 km Polluted urban areas 200 km Ecosystem area Radiometric Stability <0.1% band-to-band 0-10 hours <0.1% band-to-band 0-10 hours <0.1% band-to-band 0- 10 hours

20. 20 Multi Discipline Imager (MDI) Mirror stabilization system for image generation will require further development to meet the required precision. Large size drives cost, risk; need to optimize for science and feasibility. Instrument Performance DataTechnology Assessment / Development Needs Instrument Concept Enable scientific objectives of coastal ocean, atmosphere, and biosphere. Capable of pointing anywhere on visible Earth hemisphere. Measurement parameters adjustable: dependent on science objective. Employs three focal planes/bands Two Si: 1k (spectral) x 2k (spatial) Rockwell hybrid focal plane One HgCdTe: 256 x 2k Rockwell hybrid focal plane 4.5 m3.0 m 1.2 m Spectral Bands: 300-556, 340-1139, 1240, 1640 nm Spectral Resolution: 0.75 (3x sample), 0.8, 40, 40 nm SNR: > 1000 (bands 1, 2); > 500 (bands 3, 4) Spatial Resolution: 300 m pixels, Coverage: 500 km Temporal Resolution: < 1 hour

21. 21 Satellite Mission Concept Features Technology Development Needs SC Bus & Launch Vehicle - None (over 20 geostationary launches/year) Instrument Complement: MDI Ins, UV/Vis, CO Detector Launch: ~FY2014 Launch Vehicle: Atlas V 401 or Delta IV 4040- 12 Orbit Type Geostationary 100 Degree W Longitude Real-Time Science Data Downlink with Dedicated Ground Station Disposal into Geo + 300 km Parking Orbit Performance Data (with margins) Mass: 1286 kg (payload), 4679 kg (observatory wet total) Power (Average): 930 W (payload), 1625 W (total) Data Rate: 120 Mbps (payload), 179 Mbps (total), Spacecraft Pointing (1 sigma ): 30 arc-sec control, 4 arc-sec knowledge Lifetime (years): 2 (design), 5 (goal & consumables) MDI Instrument UV/Vis Spectrometer CO Detector Earth Est. Cost: $1.3B

22. 22 Other Considerations Spacecraft and launch vehicle Advanced technology investments Ground system architecture Mission operations Cal/Val requirements, Validation program Supporting research and analysis International cooperation  No show stoppers

23. 23 Outstanding Questions Can the mission be made more affordable? – science requirements versus instrument performance/size Do instruments have to fly together? – piggy-back on commercial communication satellite? Can other instrument concepts fulfill measurement requirements? – cost, benefit, risk assessment Priority and feasibility of boundary layer O 3 measurement?  Community input  Observing system simulation  Airborne demo measurements

24. 24 Alternate Instrument Concepts Coastal Ocean Carbon Observations and Applications (COCOA)  Further Design Study Specifications Instrument mass: 45-60 kg Power: ~50 W Cost: 12-20 Million (USD RY) Optics: F/5 Cassegrain; all beryllium optics and structure; Offner Spectrometer Focal Plane Array: Commercial visible detector Length: 120 cm Primary Mirror: 70 cm diameter Secondary Mirror: 20 cm diameter Performance Spatial Resolution at Nadir: 200 meter Spectral Resolution: 5 nm between 350 and 1050 nm (140 bands) Signal to Noise: exceeding 400 between 400 nm and 900 nm

25. 25 Summary  Strategic Concept: An Earth-viewing, Hubble-like programmable observatory facility.  Geostationary orbit enables continuous, frequent, high spatial- resolution observations required to provide the scientific foundation for quantitatively connecting local and global scales of pollution, coastal ocean, and land carbon.  new and unique approach to satellite remote sensing for atmospheric composition, coastal ocean properties, and the terrestrial biosphere  no major technological impediments  Need to work hard to make concept more affordable.

26. 26 Option to Reposition Geo Longitude  Mission design study needed to determine drift rates, fuel load, ground communication requirements.

27. 27 Science Working Group Multi-Spectral Atmospheric Composition: P. DeCola (HQ, chair) S. R. Kawa (GSFC, Geo science lead) P. K. Bhartia (GSFC, LEO science lead) J. Crawford (HQ) E. Hilsenrath (HQ) M. J. Kurylo (HQ) H. Maring (HQ) W. H. Brune (Penn St U) D. Edwards (NCAR) M. Prather (UC Irvine) R. Prinn (MIT) A. Eldering (JPL) J. Fishman (LaRC) J. G. Gleason (GSFC) Additional acknowledgement to: J. Loiacono, B. Park, J. Herman, R. Knox (GSFC); J. Burrows (U Bremen); C. Bruce, M-E. Carr (JPL); G. Sachse (LaRC)

28. 28 Terrestrial Vegetation Opportunity (250 km) 2 scan/15 min Scan forest at 300-m resolution