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Status of Navy Activities in support of MISST. 28 Nov 2005. NAVOCEANO Activity Status. NAVO Operational Use of Satellite SST. Satellite SST. Mission Planning: Surface Analysis. 10km Analysis. Satellite Altimetry SSH. Tactical Support: Sound Speed Profiles And Currents
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Status of Navy Activitiesin support of MISST 28 Nov 2005
NAVO Operational Use of Satellite SST Satellite SST Mission Planning: Surface Analysis 10km Analysis Satellite Altimetry SSH Tactical Support: Sound Speed Profiles And Currents @ each grid point @t0, t1, t2, …72hr MODAS 3D Daily Analysis • In Situ Profile • XBT • Float • CTD NCOM or SWAFS Daily 72 hr Forecast
NAVO Satellite SST Data Flow FNMOC NESDIS NCEP NASA-JPL NASA-JPL Operational Models and Archive RSS AMSRE AVHRR GAC AVHRR LAC GOES Orbital DEF Files Satellite Processing System AATSR MTSAT Binary Global database Matchup Database (SSES) OcnQC ASCII FNMOC Windsat NAVO Operational Models MSG Medspiration L2P ASCII 10km Analysis FNMOC GODAE Server Fleet Support World Wide Web Public
NAVO L2P File Status • Making N-18 GAC and LAC L2P files since 10/2005 • Sent example files to MeteoFrance and JPL for feedback. Received and implemented feedback. New sample files available • XML metadata file in progress
NAVO L2P File Status • Contents of NAVO L2P files include…. Latitude Solar Irradiance SI Source Longitude SI time diff Sea ice source File time Wind speed AOD source SST WS time diff Sat zenith angle Time diff Sea ice fraction Rejection flag Bias Aerosol Optical Depth Conf flag StDev AOD time diff Proximity conf Clim diff WS source
SSES Calculation Status • Making SSES for N-16, N-17, and N-18 AVHRR GAC and AVHRR LAC • Making SSES for GOES-West and GOES-East • Obtaining AMSR-E, Windsat, MSG, and GOES-9 SST data sets from various sources. Calculating SSES for evaluation and intercomparison. • Obtaining AATSR SST data sets.
NAVO L2P File Status (Plans) • Generate N-17 GAC/LAC L2P • Partition GAC global L2P orbit files into smaller regional data files so that XML metafile makes more sense? • Evaluate/intercompare satellite SSES values for operational use • Generate METOP AVHRR L2P files • Generate GOES-West and GOES-East L2P files?
Status Navy Activities in Support of MISST Global Real-time Sea Ice / SST Analyses (IR + in situ) • 9-12 km resolution, 6 hour update cycle • available on GODAE server in NRT http://usgodae2.fnmoc.navy.mil/ftp/outgoing/fnmoc/models/ghrsst New Observing Systems Added to Ocean Data QC • orbital AMSR-E microwave SST data from RSS • MSG SST data from CMS Blended MW/IR SST Analyses • measurement error specified by reported SSES • representation error from background SST gradients • error consistency and validation studies performed
Navy ocean data quality control system upgraded to handle orbital AMSR-E MW SST data from RSS • QC Procedures: • background field check (with appropriate errors) • climate • global/regional analysis • water mass classification • diurnal warming detection • Examples of sequential orbits processed for 30 Sep 2005 • rejections (perr>0.99) in red
Global SST analysis backgrounds used in QC of sample AMSR-E orbits 9-12 km resolution, 6 hour update cycle 30 Sep 2005 18Z 1 Oct 2005 00Z AVHRR GAC in situ AVHRR GAC in situ
Global SST background error standard deviations (°C) valid 30 Sep 2005 used to QC AMSR-E orbits x = observed SST = background SST = background error SD p = probability error reject if p>0.99, ~3 • Background Error Variances in Navy Analysis System • vary by position, depth, and analysis variable • evolve with time, updated continuously using analyzed increment fields • error growth parameterization in data void areas • function of age of data on grid and temporal autocorrelations • errors asymptote at climate variability in long term absence of observations
AMSR-E SST data very consistent with AVHRR/in situ analysis backgrounds - analysis differences ~ +/- 2°C climate background differences ~ +/- 4°C 20 UTC 21 UTC Frequency distributions of AMSR-E SST minus background SST for 30 Sep 05 sample orbits Red - global 9-12 km analysis Green - regional 9 km north pole analysis Blue - GDEM SST climatology 23 UTC
Locations AMSR-E Rejections 1 July - 1 October 2005 # retrievals = 512,939,677 # rejections = 1,384,503 (0.26%) Frequency distribution rejected AMSR-E anomalies from global analysis Binning interval = 0.5°C Max frequency = 339,191at -1.5°C 17,940 retrievals with anomalies > 4°C Bias rejected observations = -1.95°C Temperature °C
Water Mass Classification AMSR-E SST Frequency distribution of AVHRR GAC SST in Brazil Malvinas Current region for month of July (2001-2004) with mixture of normal probability distribution functions that best describes observed frequency distribution • Water mass classified AMSR-E SST retrievals for 16-17 July 2005 • clearly shows fronts and eddies • water mass classification categories used in analysis data thinning procedures • maintains SST gradients in analysis
Snapshot Blended MW-IR-In situ SST Analysis 27 Aug 2005 00Z 9-12 km resolution 12-hr update cycle Satellite SST In Situ SST AVHRR/GAC AMSR-E Ship, Buoy (fixed, drifting) Analysis Increments Analyzed SST
Blended MW/IR Analysis Verification - August 2005 12-hr update cycle, 9 km resolution North Atlantic Basin • cold start from climatology on 1 Aug 2005 • systematic reduction in RMS error from climate to innovation (previous analysis) to residual (current analysis) • analysis residuals unbiased • innovation biases show diurnal variability
Analysis Observation Error Standard Deviations • sum of a measurement error (em) and a representation error (er) • eo = em + er • measurement errors specified by SSES from data providers • computed from buoy match-ups, varies with retrieval type and time • representation errors function of resolution model and resolution of observing system • satellite retrieval error computed as function background horizontal gradient (b) when retrieval resolution (rs) exceeds grid resolution (rg) • er = b· (rs / rg) rs > rg • primarily affects AMSR-E 25-km retrievals at analysis grid resolutions of 9-12 km (AVHRR 8-km GAC retrievals not affected) • AMSR-E errors increased 2-fold in western boundary currents
Jmin Diagnostic MW/IR Analysis - August 2005 • measures consistency of specified error variances (observation and background) with innovation vector • expected value is one if consistent • < 1 error variances too large • > 1 error variances too small or erroneous data assimilated • AMSR-E SSES plus gradient representation error very consistent
Plans Navy Activities in Support of MISST Impact Studies Blended MW/IR SST Analyses • NOGAPS forecasts (T239, ~55 km resolution), focus on 2005 hurricane season (Jun-Oct) • add AMSR-E MW data to real-time GHRSST analyses Ocean Data QC • work with RSS to understand AMSR-E rejections • improve background error statistics in QC • evaluate AMSR-E diurnal warming estimates Jmin Diagnostic • continue evaluation of gradient representation error • feedback to data providers on inconsistencies in SSES measurement errors