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MODIS Winds Applications to NWP/Data Assimilation studies; Fairbanks, 10/08/2003 Lars Peter Riishojgaard Yan-Qiu Zhu Global Modeling and Assimilation Office NASA Goddard Space Flight Center Preparation for operational assimilation MODIS winds in the DAO
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MODIS Winds Applications to NWP/Data Assimilation studies; Fairbanks, 10/08/2003 Overview Data assimilation at Goddard and the JCSDA Characteristics of the MODIS winds Results from pre-operational testing Summary and outlook
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MODIS Winds Applications to NWP/Data Assimilation studies; Fairbanks, 10/08/2003 GMAO New Office at Goddard, formed via a merger of the DAO and NSIPP (NASA Seasonal to Interannual Prediction Project) Head of Office: Michele Rienecker Modeling New model targeted for 04; based on fv dynamical core, but with NWP-tuned physics Analysis Last PSAS-based system being frozen Next system will be based on GSI developed at EMC
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MODIS Winds Applications to NWP/Data Assimilation studies; Fairbanks, 10/08/2003 MODIS winds pilot period assimilation experiments in the DAO Control (all standard observations; no MODIS winds) MODIS winds used “as is”; no filtering, no modification Interactive height assignment with p max =150 hPa Interactive height assignment with p max =75 hPa
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MODIS Winds Applications to NWP/Data Assimilation studies; Fairbanks, 10/08/2003 Preparation for operational assimilation of MODIS winds Extensive experimentation with near-real time winds provided by CIMSS starting 07/02/2002 with versions 1.3r6 and 1.4r1 of the fv-DAS Main changes with respect to 1.2r5 (pilot period) Increased weight given to ITOVS Additional ITOVS data in polar areas Modified background error covariance Main metrics Consistency of data delivery Quality of MODIS winds Contribution to forecast skill
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MODIS Winds Applications to NWP/Data Assimilation studies; Fairbanks, 10/08/2003 MODIS experiments I.Basic - MODIS winds used "as is" II.Height adjustment - the heights of MODIS winds are adjusted by minimizing a cost function III. Quality indicator-based selection; only MODIS winds with q i larger than 0.80 are used IV.Retuned o ; error for MODIS wind is tuned using maximum likelihood technique V.“ECMWF filtering”: over land winds used above 400 hPa; over sea, IR winds above 700 hPa and WV winds above 550 hPa VI.DAOTOVS exclusion: Interactive TOVS retrievals beyond 65S removed
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MODIS Winds Applications to NWP/Data Assimilation studies; Fairbanks, 10/08/2003 Experimental results Innovations (observation minus forecast residuals) RAOB heights and winds ITOVS heights MODIS winds Impact Troposphere Stratosphere Forecast skill
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MODIS Winds Applications to NWP/Data Assimilation studies; Fairbanks, 10/08/2003
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MODIS IR U, V innovations for NH control (solid), MODIS; Arctic
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MODIS Winds Applications to NWP/Data Assimilation studies; Fairbanks, 10/08/2003 MODIS WV U, V innovations for NH control (solid), MODIS; Arctic
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MODIS Winds Applications to NWP/Data Assimilation studies; Fairbanks, 10/08/2003 RAOB U, V innovations for control (solid), MODIS; Arctic
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MODIS Winds Applications to NWP/Data Assimilation studies; Fairbanks, 10/08/2003 RAOB U, V innovations for control (solid), MODIS; SP
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MODIS Winds Applications to NWP/Data Assimilation studies; Fairbanks, 10/08/2003 RAOB height innovations for control (solid), MODIS; Arctic region
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MODIS Winds Applications to NWP/Data Assimilation studies; Fairbanks, 10/08/2003 RAOB height innovations for control (solid), MODIS; South Pole
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MODIS Winds Applications to NWP/Data Assimilation studies; Fairbanks, 10/08/2003 ITOVS height innovations; Arctic region
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MODIS Winds Applications to NWP/Data Assimilation studies; Fairbanks, 10/08/2003 ITOVS height innovations; Antarctic region
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MODIS Winds Applications to NWP/Data Assimilation studies; Fairbanks, 10/08/2003 Mean analyzed 500 hPa geopotential heights for July, 2002, for MODIS I run; NH (top left) and SH (bottom left); RHS shows difference fields (MODIS minus control).
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MODIS Winds Applications to NWP/Data Assimilation studies; Fairbanks, 10/08/2003 NCEP mean anlyzed 500 hPa heights, July 2002, Anarctica
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MODIS Winds Applications to NWP/Data Assimilation studies; Fairbanks, 10/08/2003 Control minus NCEPMODIS minus NCEP
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MODIS Winds Applications to NWP/Data Assimilation studies; Fairbanks, 10/08/2003
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Summary: MODIS winds complement other observations at the highest latitudes; more so in the SH than in the NH due to the current data sparsity Consistency of data delivery is acceptable Based on independent verification and innovation statistics, the quality of the information is acceptable Positive contribution to forecast skill, but not where one would expect it the most Current version of fv-DAS is hostile to high- latitude wind information
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MODIS Winds Applications to NWP/Data Assimilation studies; Fairbanks, 10/08/2003 Outlook MODIS winds experiments with new GMAO assimilation system based on GSI (next-generation EMC analysis ) Impact Background error covariance Timeliness MODIS winds from Aqua ECMWF verification if possible
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