MODIS OCEAN QA Browse Imagery (MQABI Browse Tool)

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MODIS OCEAN QA Browse Imagery (MQABI Browse Tool). NASA Goddard Space Flight Center Sept 4, 2003. MQABI/QAPS Team. Kevin Turpie - technical lead, statistics, graphics software Aumber Bhatti - web site and system software - PowerPoint PPT Presentation

Transcript of MODIS OCEAN QA Browse Imagery (MQABI Browse Tool)

  • MODIS OCEAN QA Browse Imagery (MQABI Browse Tool)

    NASA Goddard Space Flight Center Sept 4, 2003

  • Kevin Turpie - technical lead, statistics, graphics software

    Aumber Bhatti - web site and system softwareDonna Thomas - L2 graphics and operations supportRon Vogel - time series graphicsMQABI/QAPS Team

  • MQABI as a portal to MODIS Ocean DataQA browse tool provides access to 39 km resolution global maps for all Ocean products as they are produced in forward and reprocessing streams.Temporal resolutions of daily, weekly, monthly, and yearlyImages filtered for each quality level (best, good, fair, all)Quality level map image (spatial distribution of quality levels)

  • MQABI Data analysis toolsHistograms of data for all quality levels for nominal range statistics for global maps (all temporal resolutions)Full range statistics of all quality levels for global maps Time series statistics (weekly, monthly) for global and 16 oceanographic regions (all quality levels)Time series plots of weekly means (select parameters)Toggle global images between different quality levels Download Level 3 Mean and Quality HDF files directly from the web siteTime Series movie loop feature (display successive images), Movie maker feature (create a movie and download it)

  • Ocean QA WebsiteAccess to browse toolData Quality SummariesKnown ProblemsQuality Level Flags

  • All parameters displayed(weekly 39 km images)

    Thumbnail GIFs are QL = 0Pull down menu for each product has linksto statsClick on each individual product in the View All Page and you get a pop up image that has direct links to GDAAC to order data for that product, for any resolution and map type

  • Order from GDAAC 4km, 36km, 1 degree resolution: Common Flags, Std. Deviation, Number of Observations, Mean, Quality Map for this product and this data date

  • From daily to weekly tomonthly, lower quality levels are not included in the binning average, unless thats all thats available. Results in more complete coverage at better quality.

  • Time series statistics are calculated for global maps and 17 oceanographic regions

    15 regions modified from Watson Gregg

    Open ocean and coastal regions:> 1000m isobath

  • All Chlorophyll time series plots also include SeaWiFS chlorophyll on the same plot

  • Chlorophylltime seriesOverview page of all regions

  • North Atlantic weekly chlorophylls

    QL=0-1Global weekly water-leaving radiancesQL=0Terra Mission Time Series: overview of the data values for the entire mission

  • Aqua Primary ProductivityTime series

  • MQABI as part of the MODIS Ocean QA Process

  • Aspects of QARun-time QA: automatic setting of QL flags at pixel level, internal to the codeProcessing QA: Using 39 km maps, identify problems and track down system errors or processing code errors. Every single parameter (imagery and statistics) is viewed for daily weekly, monthly, yearly files as they are produced.Science QA: calibration relevant to ocean radiances, analysis of upstream products impacting downstream, refinement of algorithms, validation against in-situ measurements - ongoing by U.Miami and individual algorithm scientists

  • Processing QA

  • ConclusionMuch information for data analysis already resides on the web at MQABI of 39 km maps, statistics, time series (text listing and plots), and movie loops are availableMean and Quality HDF files can be downloadedMQABI dual use: a browse tool for the science community and for routine processing QAQA web page contains Data Quality Summaries, Known Problems, and many other documents

    Point out new features: Level 2 QA, Science Test web interface, tutorial on how to order data from GDAAC using MQABI. Mention links to OPP web site. Next slide is Level 2 pageFor the same data day, matching terra and aqua granules are selected. The web page displays all of the parameters in the level 2 file MODOCL2B and MYDOCL2B as well as the daytime SST from MOD28L2 and MYD28L2 .Next slide shows order page Text files of statistics are made for each product for each region and are used to create the time series plots which are on the next slidesAlso perform QA of Science tests to ensure that code behaves as expected before it is put into productionThe MODAPS web pages allow us to verify the successful production of data from Level 2 through Level 4. This page for example shows that all of the correct level 2 granules were produced for a data day. The top row is the Level 1B data (geolocation) and the other rows are the Oceans Level 2 data types. The small squares represent each five minute granule.