4-d Digital Camera: Horizontal: Horizontal: Large area format Focal Plane detector Arrays Vertical: Vertical: Fourier Transform Spectrometer Time: Time: Geostationary Satellite EO-3 “GIFTS” GIFTS Geostationary Imaging Fourier Transform Spectrometer GIFTS - Paving the Way for HES W. P. Menzel and W. L. Smith

The road to HES-IR VAS (1980-) GOES Sounder (1994-) GIFTS (2008-) (12) (18) (~1600) HES (2012+) time VTPR, HIRS (1972, 1978-) CrIS (2009-) IASI (2005-) AIRS (2003-) HIS (1986-) IRIS (1969) (~2400) (~3600) IMG (1997) NAST-I (1998-)

Temperature & Water Vapor IR Sounder Staircase VAS (1980-) –1 st Geo Sounder (Spin-Scan) GIFTS (2008-) (30) (1200)HES, GOES-R (2013-) ITPR,VTPR (1972) / HIRS (1978-) CrIS / IASI (2006-) AIRS (2002-) IRIS / SIRS ( ) –1 st Sounders (1200) (1200/2800) GOES Sounder (1994-) – (3-Axis) (1200) ( ) (30) Spectral Resolving Power ( /  )  Resolving 14  m BLUE = Leo Purple = Geo

Temperature & Water Vapor IR Sounder Staircase VAS (1980-) –1 st Geo Sounder (Spin-Scan) GIFTS (2008-) (7-14) (<10)HES, GOES-R (2013-) ITPR,VTPR (1972) / HIRS (1978-) CrIS / IASI (2006-) AIRS (2002-) IRIS / SIRS ( ) –1 st Sounders (14) (14/12) GOES Sounder (1994-) – (3-Axis)  (4) ( /230) nadir only (30/20-10) (8)  Spatial Footprint (km) BLUE = Leo Purple = Geo

GIFTS Sampling Characteristics Two 128x 128 Infrared focal plane detector arrays with 4 km footprint size One 512 x 512 Visible focal plane detector array with 1 km footprint size Field of Regard 512 km x 512 km at satellite sub- point Ten second full spectral resolution integration time per Field of Regard ~ 80,000 Atmospheric Soundings every minute

GIFTS Overview Revolutionary step in observing from GEO Designed to deliver 16,000 4-km soundings every 11 sec from spectra at 0.6 cm -1 res. Consistent and accurate calibration (< 3-sigma) Signal-to-noise ratios of several hundred Has “raised the bar” for the Hyperspectral Environmental Suite (HES) for GOES-R

GIFTS Sensor Module Technologies

GIFTS to HES 7 key technology demonstrations (NMP) Imaging FTS - First real design of geo FTS with adequate S/N Long wave IR detectors – Larger focal plane array enabling much improved coverage rates shown to be feasible (although fabrication not completed ). Active cooling - Long lived compact “mini cooler” paving the way for active cooling, leading to improved performance on GOES-R (fabrication not completed ) Light weight optics - Minimizing mass and enhancing thermal stability for improved near local midnight performance High speed Analog to Digital conversion – Required for the fast HES sampling rates Active Pixel Sensor – Visible detector array enabling sub-pixel cloud detection Star tracker – Refining pointing control for processing image loops

GIFTS to HES Other technology areas Laser. Enabling stability for geo- interferometer systems Calibration. Proper calibration of high-spectral resolution data being demonstrated via internal, high-quality blackbodies. Processing. Preprocessing to radiances (Level 0 to Level 1) producing soundings and winds (Level 1 to Level 2) defined and processing implications evaluated.

Status of Sensor Module & Test Readiness Subsystem CDRs have been conducted and system design is nearly complete All key New Millennium technologies will be delivered within months System needs to be assembled & tested to prove the thermal/mechanical design and the Imaging FTS enabling technology Test Facilities are mainly ready

Performance Exceeds Requirement (Noise performance twice as good as required in key regions ) Estimate based on measured focal plane array detector and readout performance characteristics

EDU would provide * Demonstration of several key technologies working together (active cooling, FPA, FTS, high speed A/D, lightweight optics, operation at cryogenic temperatures) * Identification of the risks during integration * Characterization of full system (scan mechanism, beam splitter, FPA, cooler, sampling system, fast A/D, reference blackbodies) performance, including - noise from interferometry - noise from FPA detector and readouts - noise from fast A/D - non-linearities - radiometric and spectral calibration * Completion will provide many useful lessons as risk reduction for the GOES-R HES

GIFTS Science Status Products: Water vapor (soundings, fluxes, winds) Temperature (sounding, stability) Carbon monoxide concentration (2 Layers) Ozone concentration (4 Layers) Surface Temperature and emissivity Clouds (altitude, optical depth, microphysical properties, winds) Aerosol Concentration and Depth (8.8 to 14.6 microns)(4.4 to 6.1 microns)

ER-2 NAST Data Used to Demonstrate the Accuracy of the GIFTS Wind Measurement Concept (Errors < 4 mps) Direction (Degrees) Pressure (mb) Speed (mps) February 11, N, 121.6W GOES - IR X Off California Coast Doppler LIDAR NAST

December 5, 2003 NAST Used to Demonstrate the Ability to Retrieve Accurate Soundings Down to Opaque Cloud Levels and Below Optically Thin Cirrus Cloud Visible IR Flight Track Thin Cirrus

GIFTS to HES Science areas Shortwave side of the water vapor band. “Non-traditional" side of water vapor band shown to have advantages for moisture retrievals. Hyperspectral Simulations. Simulations of radiance cubes, for both clear and cloudy skies, helping to develop HES algorithms. Winds tracking in retrievals. Atmospheric motion vectors from inferred by tracking features time sequences of moisture soundings. Soundings in thin cirrus. Demonstrations of soundings in clouds with aircraft hyperspectral data. Education. HES proposals will be better evaluated by experiences and knowledge gained from GIFTS

Conclusions Sensor Module is close to being ready for assembly Testing Sensor Module in thermal vacuum and qualifying it for flight would be most valuable This would validate the Sensor Module thermal mechanical design, prove the imaging FTS system concept, and test other technologies Wind profiling measurement concept has been validated using airborne NAST-I data NAST-I has also demonstrated that clouds will not severely limit GIFTS sounding capability Geo-GIFTS remains very desirable: flight opportunities, including international partnerships, should continue to be explored