CERES-II Kory J. Priestley Climate Science Peer Review NASA Langley Research Center June 6 th, 2007

1. CERES-II Kory J. Priestley Climate Science Peer Review NASA Langley Research Center June 6 th, 2007

2. NPP and NPOESS • NPOESS had planned to fly CERES follow-on instruments (i.e ERBS) in 1:30 orbit with launches on C1 and C3 platforms 2010 and 2015. • NPOESS seriously over budget and behind schedule: triggered Nunn-McCurdy review in U.S. congress - completed June 2006. • ERBS instrument development Cancelled. • Directed to fly CERES FM-5 on C1 platform, but now delayed to ~ 2013. • U.S. Office of Science and Technology Programs (OSTP) requested NASA and NOAA produce a white paper on how to deal with the NPOESS climate instrument deletion • Joint NASA/NOAA white paper submitted to OSTP Jan 2007: recommended moving CERES FM-5 up to flight on NPP mission in 2009, build CERES-II instruments to fly on the NPOESS platforms in 2013 and 2018. • NOAA and NASA budgets do not currently include such funding, it remains to be seen how this is dealt with. Answers needed within 3-4 months. • Feasibility studies of CERES on NPP for spacecraft, instrument, & ground data system modifications are underway. • So far no show stoppers: more detailed studies expected with decision on go/no-go in late summer this year.

3. CERES FM5 ERBS FM1 ERBS FM2 CERES PFM CERES FM1,2 CERES FM3,4 Earth Radiation Budget Measurement Flight Schedule Original Plan - Circa 2000 -

4. Earth Radiation Budget Measurement Flight Schedule Current Scenario CERES FM5 CERES PFM CERES FM1,2 CERES FM3,4

5. Earth Radiation Budget Measurement Flight Schedule Climate Instrument ‘Recovery’ Plan CERES FM5 CERES II FM1 CERES II FM2 CERES PFM CERES FM1,2 CERES FM3,4

6. Earth Radiation Budget Measurement Flight Schedule Climate Instrument ‘Recovery’ Plan CERES FM5 CERES II FM1 CERES II FM2 CERES PFM CERES FM1,2 CERES FM3,4

7. Radiometric Performance Requirements 5-Year CERES II Mission Lifetime • Requirements for CERES are more stringent than ERBE’s by a factor of 2 • Requirements per Ohring et. al. are more stringent than CERES by a factor of 3-5

8. ‘CERES II’ Instrument • Philosophy • Evolutionary update of existing CERES hardware/Design. • Emphasis will be on accuracy/performance improvements and not increased measurement capability. • Capitalize on experiences and ‘Lessons-Learned’ of CERES Program. • Implement a two-pronged approach • Hardware • Programmatics

9. ‘CERES II’ Instrument • Philosophy • Evolutionary update of existing CERES hardware/Design. • Emphasis will be on accuracy/performance improvements and not increased measurement capability. • Capitalize on experiences and ‘Lessons-Learned’ of CERES Program. • Implement a two-pronged approach • Hardware • Programmatics • Constraints • Already driven by Schedule • NPOESS C1 Launch Scheduled for January, 2013 • Spacecraft Need date typically L - 18months = June, 2011 • Instrument Build requires a ~ 36 month schedule (I.e. L-54 months) - June, 2008 Contract Start Date. • Procurements in excess of $100M require a 12 month process… • Instrument Specification, SOW, and commitment from Agency needed ASAP!

10. Design Fab, Assembly and Test Changes • Hardware • Calibration Equipment - Provide Additional SW Spectral Characterization Capability • Spectral Shortwave Internal Module (SSWIM) • Mirror Attenuator Mosaic (MAM) Solar Diffuser • General Design • Detectors - transition to Thermopiles, increased responsivity, Minimal Thermal Control req’d. • Replace WN channel with True LW - Increased Redundancy • Alternative Mirror Coatings - (Al, Ag, Al-Ag hybrid) • Reduced FOV - 10 km vs. 20km • Programmatics • Improved Ground Characterization • Implement automated Data Acquisition System on Calibration Chamber • Establish collaborations with NIST • Handling Procedures • Minimize Possibility of Contamination • Develop inspection and cleaning procedures • Even Stronger emphasis on calibration during test program • Increase weighting/influence of Radiometric Performance in cost/schedule trades

11. CERES II Onboard SW Calibration Equipment Shortwave Spectral Internal Module (SSWIM) • Either lamps with spectral filters or a series of monochromatic sources • Ability to vary strength of source preserved • Contains independently monitoring of source output • Design specification is 0.1% stability over 5-year mission • Designed primarily to spectrally resolve changes in optical transmission Mirror Attenuator Mosaic (MAM) Solar Diffuser • Solar Diffuser plate attenuates direct solar view (~5800K Spectrum) • MAM is currently a Nickel substrate with Aluminum coated spherical cavities or divots • Provides a Relative calibration of the Shortwave channel and the SW portion of the Total channel • Designed to provide a long-term on-orbit SW calibration source.

12. Global Ozone Monitoring Experiment Spectral Darkening on Earth Observing Missions Spectral Darkening of Optical Surfaces in the SW region is a significant concern for Climate Quality Instruments Wavelength / Radiometric Channel (um) Contamination and UV exposure of spare CERES Quartz filters with Penzane MODIS Solar Diffuser Yr 1 Yr 2 Yr 3 SD degradation (accumulated at a 6-month period) as a function of wavelength Faster degradation rate after fixing the SD door at “open position” Yr 4 Yr 5 500 Wavelength / Radiometric Channel (nm)

13. 0 1 2 3 4 Wavelength (micron) 0 1 2 3 4 Wavelength (micron) Spectral Degradation : SWICS vs. Earth Spectra 1.0 0.8 0.6 0.4 0.2 0.0 Spectral Response, Normalized Radiance

14. SW Internal Calibration Results

15. CERES SSF Ed2B SW TOA Flux Anomaly Clear Ocean Clear Desert

16. Handling Procedures and the Blame Game In order to fit within the launch Vehicle Fairing, Aqua spacecraft designed deployable platforms for the CERES instruments. The S/C Deployment Drive Actuators (DDA’s) S/C leaked penzane lubricant - a known design issue. CERES Project expressed concerns regarding possible contamination but had no definitive proof of possible measurement degradation… CERES Project’s concerns noted…

17. Foggy Aqua CERES FM-3 MAM Contamination Cover • Subsequent to spacecraft level thermal vacuum testing, a visual inspection of the FM-3 instrument revealed a ‘fog’ on the interior surface of the FM-3 MAM contamination cover. • Visual inspection of optics revealed no visible deposition. • Testing yielded conflicting opinions of the material, most likely candidate was penzane lubricant.

18. Design Fab, Assembly and Test Changes • Hardware • Calibration Equipment - Provide Additional SW Spectral Characterization Capability • Spectral Shortwave Internal Module (SSWIM) • Mirror Attenuator Mosaic (MAM) Solar Diffuser • General Design • Detectors - transition to Thermopiles, increased responsivity, Minimal Thermal Control req’d. • Replace WN channel with True LW - Increased Redundancy • Alternative Mirror Coatings - (Al, Ag, Al-Ag hybrid) • Reduced FOV - 10 km vs. 20km • Programmatics • Improved Ground Characterization • Implement automated Data Acquisition System on Calibration Chamber • Establish collaborations with NIST • Handling Procedures • Minimize Possibility of Contamination • Develop inspection and cleaning procedures • Even Stronger emphasis on calibration during test program • Increase weighting/influence of Radiometric Performance in cost/schedule trades