GOES-R Calibration Working Group: Progress and Status

1. GOES-R Calibration Working Group: Progress and Status Jared Clarke CWG/GOES-R Program Liaison

2. GOES-R Program Overview • Objective: Provide the next generation in US geosynchronous meteorological products • Flight Project: NASA-led effort to develop and procure spacecraft and instruments • Ground Segment Project: NOAA-led effort to develop and procure ground system, product algorithms and delivery

3. GOES-R Payload • Advanced Baseline Imager (ABI): Imaging radiometer • Based on GOES-I/P Imager, MODIS • Geostationary [sic] Lightning Mapper (GLM): Lightning optical event detection and location • Based on the TRIMM OTD • Pathfinder in GEO • Solar Ultraviolet Imager (SUVI): Solar imaging in hard/extreme UV • Based on GOES-N/P SXI • Extreme Ultraviolet Irradiance Sensor (EXIS): Extreme UV solar flux • Based on GOES-N/P XRS • Magnetometer (MAG): Geomagnetic field • Heritage from NASA MRO, GOES-I/P • Space Environment In-Situ Suite (SEISS): Suite of space-based particle radiation detectors (electron, proton, heavy ion) • Based on the GOES-N/P SEM (including EPS/HEPAD) • Communications • Product Data Relay (GOES-R Rebroadcast--GRB) • Ancillary Communications (SARSAT, EMWIN/HRIT, DCS)

4. CWG Responsibilities • Ensure that L1b data products for all instruments are well-calibrated and referenced to open standards over their useful lives • Provide expertise to the full GOES-R Program in calibration science and applications • Technical oversight of instrument calibration functions, measurements and algorithms (pre-launch) • Perform post-launch calibration verification & validation • Provide long-term calibration maintenance for all instruments to end-of-life • Identify opportunities for the highest quality calibration measurements, capabilities and processes possible within the scope of the GOES-R Program

5. Ongoing Activities • Instrument Development • CWG-assigned Subject Matter Experts providing direct input to the GOES-R Flight Project and instrument vendors • Oversight of L1b algorithm development, on orbit verification planning • Flight & Ground Segment Reviews • Instrument Prototype (PTM) & Engineering Model Testing (ABI, SUVI) • Oversight of test plans, methodology and execution • Ground System Development • Operational functions • Database, process development • L1b algorithm implementation oversight • Trade Studies, Whitepapers and Analysis • Response to vendor questions • Support decision making processes that impact calibration • Issues uncovered during development • Impact assessment to L1b products from test discoveries

6. Recent Progress for 2010 Key CWG Efforts

7. Instrument Development

8. Instrument Development • Review and oversight of instrument calibration plans and procedures • Prototype and Flight Model instrument builds • Assembly-level, bench testing and instrument thermal vacuum testing • Input to instrument vendor development of L1b ground processing algorithms (which include on-orbit calibration) • CWG provides concurrence before calibration algorithms are accepted from the contractor and at all review phases • Analysis of data collected from instrument and prototype testing…

9. ABI PTM Spectral Response • Analysis of ABI PTM spectral response NIST Simulated Vendor PTM SRF Investigation: Identify Concerns/Issues: PTM data are mostly in good agreement with “simulated” ABI data Bands 6, 8 & 12 are out of specification … 1 2 Identify Hyperspectral Targets Characterize Spectral Sensitivity Target Spectra

10. ABI PTM Spectral Response • Analyzed, compared multiple SRFs including: • CWG notional • University of Wisconsin “boxcar” • ABI PTM measured (instrument vendor, NIST) • Compared all SRFs to ABI requirements • Performed simple series of land classification retrievals using each set of SRF • Small but substantial differences noted

11. SUVI Pre-Launch Calibration • SUVI scaled back to be a phenomenological instrument • Piece part and subassembly measured calibration • Total instrument calibration by analysis • Currently planning UV throughput measurements at NASA/MSFC on the SUVI EDU • Verify the analysis process used for build-up of flight model calibration

12. ABI NIST/SI Traceability • Irradiance Calibration (solar diffuser) • Characterized in ambient conditions • NIST traceability of FEL • SI traceability of diffuser • Schedule: Soon • Thermal Transfer Radiometer (TXR) & Visible Transfer Radiometer (VXR) Deployments • Overall instrument SI traceability • Schedule: Late Fall/Early Winter 2010 • Traveling Spectral Irradiance using Uniform Sources (Traveling SIRCUS) • Schedule: Currently Working with ITT

13. ABI Radiance/Reflectance • Conducted an impact analysis after it was learned that the Algorithm Working Group had been assuming ABI L1b data output as reflectance factor, rather than the required radiances • Published a whitepaper outlining a strategy for meeting the requirement and accommodating L2+ algorithms • Include coefficient (κ) for transforming between LTOA and ρfin GRB as metadata • Incorporate ratio between factory given solar spectra irradiance and the Earth-sun distance

14. Ground System and Operations

15. ABI Lunar Calibration • Work completed • Determine criteria which provide opportunities to perform lunar imaging (Earthshine, ABI FOV, time of day, day of year, lunar phase angle) • Determine methods to acquire lunar images (ABI mesoscales*) • In Progress • Determine what level of data processing is needed for lunar image analysis • Planning tools for lunar imaging • Determine operational method to work with lunar image data

16. Operational Calibration

17. Operational Calibration • CWG identified that requirements for routine calibration analysis and monitoring were inadequately defined • Did not reflect a “hands-on” approach to calibration • Provided incorrect direction to the Ground System (GS) contractor (Harris Corp.) • Emphasized long-term “drift”/degradation analysis only • Developed a concept of operations for routine calibration in the GOES-R GS • Arranged a site visit for the Harris Team to witness operational calibration activities firsthand at NSOF • Working directly with OSPO Calibration Staff for requirements

18. SEISS In-Flight Calibration • The responsibility for designing the routine SEISS periodic electronics calibration was not assigned • CWG identified the missing algorithm • Currently defining the data necessary to make the calibration • CWG will design the algorithm

19. Verification and Validation

20. GLM Laser Beacon Study • Provide geographically, radiometrically known targets for GLM verification • Geolocation/Registration calibration • Radiometric throughput • Determine types, locations and practicality of deploying beacons under a variety of scenarios • Coastline measurement of performance are only possible in full sun • Study is in progress

21. ABI Geolocation/Registration GOES-9, 24 December 2008 Courtesy: T. Schmit

22. ABI Geolocation/Registration • CWG is working to identify terrestrial control points (landmarks) to verify ABI navigation • Qualitative verification of finished L1b imagery based on regional imagery enhanced with a Digital Elevation Model • Comparing ideal and realized L1b imagery • Fine discrepancies can be assessed via PSF • Gross discrepancies can be assessed via a pixel-vector

23. Magnetospheric Particle Intra-Calibration • Developed prototype algorithm for intra-calibration between particle detectors • Prototyped using GOES-13 magnetospheric electron (MAGED) data, and SWPC-provided magnetometer data • Pitch-angle corrected • Will be used autonomously for SEISS/ground intra-calibration and comparison

24. Vicarious Calibration Hyperion AVIRIS Site Characterization BRDF characterization of White Sands Missile Range, Sonoran Desert Seasonal BRDF variation Will coordinate overflights with MODIS observations Plans for overflights are in place, will likely take place Fall 2010 or Spring 2011 (pre-empted by AVIRIS support for Deepwater Horizon spill) • Hyperspectral characterization of the moon, using EO-1 Hyperion Full Moon collect • Analysis of lunar spectral characteristics in ABI bands • Developing analysis techniques to estimate detector “drift” from ABI lunar images, MTF

25. CWG Members • NOAA STAR • GOES-R Program Office • GOES-R Ground Segment Project • GOES-R Flight Project • MIT Lincoln Labs