1 March 2011iQuam GHRSST DV-WG, HL-TAG and ST-VAL Meeting 28 February – 2 March 2011, Boulder, CO In situ Quality Monitor (iQuam) Near-real time online Quality Control, Monitoring, and Data Serving tool for satellite Cal/Val Feng Xu and Sasha Ignatov NOAA/NESDIS Center for Satellite Applications and Research

1 March 2011iQuam2 Satellite SST Projects using in situ POES and GOES (including MSG, MTSAT, Electro) NPOESS (NESDIS, NGST), GOES-R SST Quality Monitor (SQUAM) Participants (L2 – NAVO, O&SI SAF; L3 – Pathfinder; L4 producers) Use of in situ SST CAL: Derive regression coefficients / Adjust bias in RTM based VAL: Monitor Accuracy/Precision of satellite SST Near-Real Time NCEP GTS Data Global Telecommunication System data available in NRT Data quality non-uniform & suboptimal. QC not available Ad hoc simplistic QC used in remote sensing community Use of in situ SSTs at NESDIS

1 March 2011iQuam3 Establish near-real time online in situ Quality Monitor (iQuam) which performs the following functions  Quality Control: Perform accurate/flexible QC for in situ SSTs, which is consistent with wider Meteorological and Oceanographic communities  Monitoring: Provide statistical summaries of in situ SSTs (stratified by ships, drifters, tropical & coastal moored; and also for individual platforms)  Data Serving: Serve QCed in situ SST data online for GHRSST community NB: although currently, only drifters and tropical moorings are used in Cal/Val, ships and coastal moorings are also included in iQuam, to explore their potential use Objectives of in situ SST Quality Monitor

1 March 2011iQuam4 Quality Control CategoryCheckType of error handledPhysical basis PreprocessingDuplicate Removal Duplicates arise from multiple transmission or data set merging Identical space/time/ID PlausibilityPlausibility checks Unreasonable field valueRange of single fields & Relationships among them Internal consistency TrackingPoints falling out of trackTravel speed exceeds limit Spike checkDiscontinuities in SST time series along track SST gradient exceeds limit External consistency Reference Check Measurements deviating far away from reference Bayesian approach (*) (Ref. SST: daily OI SST v2) Mutual consistency Cross- platform Check Mutual verification with nearby measurements (“buddies check”) Bayesian approach (*) based on space/time correlation of SST field (Correlation model: 2-scale SOAR, Martin et al., 2002) (*) Lorenc and Hammon, 1988; Ingleby and Haddleston, 2007

1 March 2011iQuam5

1 March 2011iQuam6 Monthly Statistical Summaries Outliers detected by each QC check Moments of ΔT S =T in situ - T Reynolds Histograms of ΔT S summary of statistics

1 March 2011iQuam7 Time Series of Monthly Statistics No of Platforms No of Observations Bias in ΔT S SD of ΔT S ships drifters moorings Historical Trends

1 March 2011iQuam8 Monitoring individual platforms List of platforms & individual statistics Error Rate History Time Series of ΔT S Monthly Trajectory Individual Platforms Monitor

1 March 2011iQuam9 iQuam and Black List: Recent Examples What iQuam says about these these black listed buoys? #blacklist 2009/01/ /02/10 #blacklist consolidated 2009/01/ /12/ /10/ /11/ /05/ /05/ /10/ /11/ /07/ /08/ /02/ /04/ /02/ /04/ /02/ /04/ /01/ /02/ /09/ /09/ /05/ /05/ /03/ /04/ /01/ /04/ /11/ /12/ /02/ /02/ /04/ /04/ /01/ /01/ /02/ /03/ /04/ /05/ /01/ /02/10

1 March 2011iQuam10 Data Download QCed data in HDF format available for download

1 March 2011iQuam11 Use of iQuam data in SST Quality Monitor VAL against iQuam now available in L4-SQUAM Adding VAL against iQuam in L2 and L3-SQUAM underway

1 March 2011iQuam12 Summary  NRT online in situ Quality Monitor (iQuam) implemented -QC’es in situ data. QC consistent with Meteorological and Oceanographic communities; e.g. Lorenc and Hammon, 1988; Ingleby and Haddleston, Reports statistical summaries stratified by data types (ships, drifters, tropical and coastal moored) and for individual platforms -Serves QC’ed in situ SSTs to users via ftp, in near-real time (6 hour delay)

1 March 2011iQuam13 Future Work  Documentation and enhancements -Initial version of document available at documenting in peer-reviewed literature underway  Enhancenments -Add ARGO floats & Extend time series to 1980 (currently, 1991) -Test out OSTIA vs. daily Reynolds for background check -Consider adding three-way error analyses (O’Carroll et al)  Use -Work with GHRSST to seek consensus on methodology & use -Add VAL of L2/L3 in SQUAM & explore for CAL -Explore ship & coastal moorings in satellite CAL/VAL