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Discussion (GRWG Joint Session). From R. Iacovazzi Articles to Quarterly Technical Memorandum series To GDWG Requests, questions, concerns, … From GDWG Guidance, recommendation, …. Overview of GRWG-II. Goals VISNIR algorithm Critical features, main logics Relation with IR algorithms
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Discussion (GRWG Joint Session) • From R. Iacovazzi • Articles to Quarterly • Technical Memorandum series • To GDWG • Requests, questions, concerns, … • From GDWG • Guidance, recommendation, …
Overview of GRWG-II • Goals • VISNIR algorithm • Critical features, main logics • Relation with IR algorithms • Implementation strategy • AIRS-GEO algorithm • Adequate for the given tasks? • Missed opportunities? • Other suggestions? • GRWG operations • Work as a team while … • … consistent with member’s priority/expertise
Discussion (GRWG Breakout Session) • GPRC’s responsibility • Analyze the co-located data and provide routine inter-calibration information for its GEO – yes • Perform co-location for its GEO – yes • Get the data to GPRC • Subset for each GPRC • All granule whose center is within 20° from GEO nadir (0E, 63E, 57.5E, 86.5E, 105E, 140E) • < 3GB – must be within GPRC’s communication capability • Provide the granule map and starting time • 2-5 days of data • Inform me of your NEdR • Spectral • Use Kato for >10 um and Tobin for other
Discussion (GRWG Breakout Session) • Spectral • Use Kato for >10 um and Tobin for other • Average ratio of all AIRS channels within GEO channel • NESDIS provides prox_rad with clouds at 700, 500, 300 mb. For people to study whether clear radiance is a good proxy • GRWG prepares a prioritized list of research topics • Covers 3000 cm-1
Discussion (GRWG Breakout Session) • Visible • GEO vs MODIS • DCC within 30N-30S (30 E/W?) • Histogram (rad vs freq) for GEO & LEO • Relative calibration • Initial implementation by Doelling (By GRWG-III?) • Monthly • Research • Use POLDER on A-Train and MODIS to quantify how Lambertian is DCC • How about 1.6 um for MSG. Co-location? Sunglint? • POLDER characterization of desert in sight of GOES & MTSAT, FY, COMS (midterm) • Desert • >20 km to cover all detectors and account for nav error • Errors due to sand dune orientation and sol zen angle <3%. Monitor many targets to minimize this effect • Moon • Search GEO archive to find lunar image – recommend for research
Discussion (GRWG Breakout Session) • Format • Content for each co-location GEO-hyperspectral • GEO & LEO ID • GSICS version • Date, time (sec) for geo & leo • lat/lon of pixel, geo, leo, sun, • zenith, azimuth • Radiance: env mean & stdv, fov mean & stdv • Convoluted hyperspectral radiance • Record for GEO & LEO
GSICS GEO-AIRS Algorithm • Match AIRS granule with GEO image • Fixed Space (GEO domain, ~20°) – find the matching AIRS granule • Fixed Time (AIRS granule) – find the matching GEO image • Collocation • Spatial – find the GEO pixel at the center of AIRS FOV • Temporal – time difference < 5 min • Geometric – abs[cos(geo_zen)/cos(leo_zen)-1)] < 0.01 • Azimuth angle is computed but not constrained • Uniformity – stdv of radiance within “environment” < 10*NEdR • “Environment” is ~3X3 AIRS FOV – sufficient for nav error • Normality – n*abs(fov_mean-env_mean) < 2*env_stdv, • N is the number of GEO pixels inside of AIRS FOV • Mean for AIRS FOV is not an outlier • Found if at least one channel passes all the test • Save all channel data for “complete picture” • Save all test results for later down select • Spectral Correction (Koji Kato, JMA)
Discussion (GRWG Breakout Session) • Improve Collaboration – Work as a team • Common goal • Manageable database that helps to • Characterize differences among sensors and • Identify instrument performance issues • Steps towards the goal • Consensus algorithm • Ability to exchange and use data and algorithm • Verified by benchmark data, code, and results • Distributed Research – Member take a lead in a coordinated ways • Solar bands • Broadband sensors (e.g., MODIS with GEO) • Narrow band instruments (GOES Sounder, HIRS) • Technical Issues • Data issues that GDWG should know • Output data format • Spectral convelotion • Next Meeting • When – ~six month? Avoid certain months (e.g., December)? • Where – rotate among members? • Other Topics
Distribution of ISCCP tasks ? Central requests for data Acquisition Acquisition Acquisition Central computation of reference inter-calibration coefficients
feedback Distribution of GSICS tasks for LEO-GEO Research Research Research Central provision of LEO reference data Colocated GEO Acquisition Colocated GEO Acquisition Colocated GEO Acquisition All colocated GEO Acquisition Central comparison(inter-calibrationprocessing) Routine GEO-LEOprocessing Routine GEO-LEOprocessing Routine GEO-LEOprocessing GCC functions GPRC functions