AMSR-E Team Leader Science Computing Facility

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AMSR-E Team Leader Science Computing Facility
Science Software Status
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AMSR-E Science Software Status

• L2A Brightness Temperatures V10
• April 2009
• Compute a checksum from Latitudes, Longitudes,
  and Tb's, attach it to the L2A file as a global
  attribute, and report it in the QA file. This
  aids in corrupted file recognition.
• RSS added the glint angles of the DirecTV 10 and
  11 satellites to the Geostationary_Satellite_Glint
  _Angles field.
• L2B Ocean V06
• October 2007
• Last algorithm updates version V05, April 2007

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AMSR-E Science Software Status

• L2B Land V09
• December 2008
• Promote the product maturity status to Validated
• Modify TLSCF software to accommodate an
  incompatible shell command on the Science Team's
  hardware
• Last algorithm update version B05, March 2006
• L2B Rain V10
• October 2007
• First Linux version
• No algorithm changes
• Significant algorithm update expected soon

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AMSR-E Science Software Status

• L3 Ocean V04
• May 2010
• Add RFI filtering for DirecTV this affects the
  United States west coast and the Caribbean
  Islands
• Add RFI filtering for Atlantic Bird 4 in the
  Mediterranean Sea
• Add RFI filtering for the Ascension Islands and
  in the Gulf of Aden
• Update RFI filter for Hotbird/Astra
• Update Aral Sea filters
• Include the RFI angle grid in the product

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AMSR-E Science Software Status

• L3 Land V06
• December 2008
• Promote the product maturity status to Validated
• Modify TLSCF software to accommodate an
  incompatible shell command on the Science Team's
  hardware
• Last algorithm update was version B04, May 2007

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AMSR-E Science Software Status

• L3 Snow V09
• December 2008
• Promote the product maturity status to Validated
• Modify ancillary file format
• Last algorithm update version B07, April 2006
• L3 Rain V06
• April 2008
• Promote the product maturity status to Validated
• Skip duplicate (overlapping) scans in consecutive
  L2A files

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AMSR-E Science Software Status

• L3 Rain V06 continued
• Improve L2A Brightness Temperature binning for
  monthly ocean grids
• Update the leap second ancillary file to include
  the leap second which occurred at the end of 2005
• Adapt the software package to run under Linux
• Add a shell script which is used during
  installation.
• Use larger system stacksize parameter
• Update expected soon

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AMSR-E Science Software Status

• L3 Sea Ice V12
• March 2010
• Update a result of anomalies observed by the
  science team during reprocessing
• Significant changes to TLSCF software to manage
  intermediate files and ensure correct
  reprocessing
• Production rules updated
• Multi-year sea ice mask and snow melt mask now
  stored within the 12.5 km product file
• Known bug in code that calculates the sea ice
  concentration difference arrays

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AMSR-E Science Software Status

• L3 sea ice multi-year mask used in snow depth
  over sea ice processing in version T08 V11
• Initiated on October 1st of each year by the
  science code
• The algorithm then generated a dynamic multi-year
  ice mask each day (intermediate file) to be used
  in the next days processing
• Used default file when an intermediate file was
  not available
• Used default at start of any reprocessing stream

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AMSR-E Science Software Status

• Multi-year sea ice mask issues
• The science team noticed anomalies in products
  whose reprocessing streams started on dates other
  than October 1st
• Due to the dynamic nature of the mask
• Reprocessed data whose processing streams began
  in the middle of a sea ice season (January, for
  instance) were compromised due to the use of the
  default mask file
• The SCF discovered that incorrect intermediate
  files were being used at the SIPS to generate the
  final products
• Result of preliminary and final products
  processed in same location
• The intermediate mask files are overwritten each
  time the code is executed, causing inappropriate
  intermediate files to be used when a final
  product was made

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AMSR-E Science Software Status

• Multi-year sea ice mask software resolutions
• Use default mask to initiate the data processing
  ONLY for beginning of mission (June 2002)
• Store the mask in the daily 12.5 km product
• Write the data date to the mask file when it is
  created and check the date before using in
  processing
• Require that the mask date precede the data date
• Add a command line argument to accommodate large
  data gaps
• Command line argument is a 12.5 km product file
  from which the mask file is extracted
• This is an override condition the default
  condition is to use the intermediate mask file

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AMSR-E Science Software Status

• Multi-year sea ice mask software resolutions
  (continued)
• Under default conditions, if the intermediate
  mask file is more than 7 days old, processing
  stops without making a product
• Under override conditions, i.e., if a previous
  12.5 km product is given on the command line, the
  mask within the product will be extracted,
  processing will continue, and the metadata
  science quality flag will be set to Suspect if
  the masks are more than seven days old.

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AMSR-E Science Software Status

• Multi-year sea ice mask production rules
• Sea ice shall be reprocessed from the beginning
  of mission forward
• If there is a data gap, then the mask file
  immediately preceding the gap is to be used
• Process preliminary and final products in
  separate locations

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AMSR-E Science Software Status

• Multi-year sea ice mask
• Lots of exception code
• October 1st, missing data on October 1st, data
  gaps, intermediate files, date checking,
• Additional QA code
• Numerous scenario testing
• Close coordination with the SIPS concerning
  processing rules
• Similar issues and resolutions for the snow melt
  mask

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AMSR-E Science Software Status
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New AMSR-E Product

• L3 Sea Ice Drift
• B01
• TLSCF code
• Metadata
• QA
• Integration and test at TLSCF
• DAP delivery to the SIPS
• Integration and test at SIPS
• ESDT testing between SIPS and NSIDC

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New AMSR-E Product

• L3 Sea Ice Drift
• Daily sea ice motion in the Arctic derived from
  AMSR-E 89 GHz 6.25 km resolution Tbs
• Uses the 6.25 km and 12.5 km AMSR-E sea ice
  products as input
• Uses a 5 day window, so that for each output day
  it requires the current day, the two previous
  days and the two following days
• Initially for northern hemisphere southern
  hemisphere will added later

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New AMSR-E Product

• L3 Sea Ice Drift File Sample (header)
• Arrow number 292 (Number of vectors in the
  file)
• Tracking period (day) 4
• Tracking method Grid
• Grid Size (pix) 16 (There is a vector every 16
  pixels)
• Contour threshold 0.040 (Maximum range in pixels
  that the ice is tracked)
• Contour Size limit (pix) 100
• Contour X-axis limit (pix) 25
• Contour Y-axis limit (pix) 25
• Tracking range (pix) 16
• Moving limit (pix) 8.000000
• Frequency (GHz) 89
• Resolution (km) 6.25
• Row 1024 (Output grid is a subset of the 6.25
  km grid, 1024 x 1024)
• Column 1024

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New AMSR-E Product

• L3 Sea Ice Drift File Sample (data)

212 580 218.000 588.000 10.000 228 564
228.833 566.833 2.953 228 580 232.500
585.250 6.915 228 628 232.333 632.333
6.128 228 660 232.000 666.000 7.211
The first two numbers are the x,y coordinates of
the starting grid point, the next two are the x,y
coordinates of the ending grid point, the last is
the displacement of the ice template in pixels
(the distance from the first to second
coordinates).
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Algorithm Updates - LANCE

• AMSR-E Real-time processing support
• Update metadata generation routines for all
  science software to recognize the product
  maturity code R for real-time processing
• Update the metadata input pointers to accurately
  reflect the product maturity code
• Update the L3 science software to recognize file
  names with a product maturity code of R
• New delivery of all DAPs to SIPS

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Algorithm Updates

• L2 Rain significant changes
• L3 Rain significant changes
• L3 Sea ice bug fix that affects the difference
  arrays
• L3 Snow
• L2 Land ?
• L3 Land ?
• New L3 sea ice drift

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AMSR-E L2A Quality Flags

• L2A Flags
• Scan_Quality_Flag
• 4-byte
• Per scan
• Pertain to all observations of a scan including
  all Level-1A and resampled channels.
• Identical flag repeated in each swath
• Channel_Quality_Flag
• 2-byte
• Per scan
• 12 channels for the Low Resolution Swath
• 2 channels for each of the High Resolution Swaths
• The summary bit 0 of the Channel_Quality_Flag is
  automatically set whenever any of the bits in the
  Scan_Quality_Flag are set.

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AMSR-E L2A Scan Quality Flag
Bit Flag Description (nominal value0)
0 Summary flag Set if any of the other bits are set
1 Antenna Spin Rate Set if spin rate is out of range
2 Navigation Set if the position or velocity of the navigation data for that scan is out of bounds
3 RPY Variability(only AMSR-A) Set if the roll, pitch, or yaw variability from scan to scan is out of bounds
4 Roll, Pitch, Yaw Set whenever the roll, pitch, or yaw exceeds 2.0 degrees
5 Earth Intersection Set if any of the observation locations fail to fall on the Earth
6 Hot Load Thermistors Set whenever the thermistors on the AMSR hot load are out of bounds
7-31 Not used
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AMSR-E L2A Channel Quality Flag

• Bit 0 is set if any of the bits 2 through 15 are
  set, also set whenever any of the bits in the
  Scan_Quality_Flag are set.
• Bit 1 set if no TB was computed for this channel
• Bit 2 set for first and last scans
• Bit 3 set if there are serious calibration
  problems
• Bits 4,5, 7-10 quality of thermistors, hot /
  cold counts
• Bit 11 set if there is a geolocation error as
  reported by the Scan_Quality_Flag
• Bit 6 indicates if Teff is dynamic or static
• Bit 12 set if Teff is not available

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AMSR-E L2A Quality Flags

• L2A Quality Flags
• Extremely useful to end users
• Easy to incorporate in algorithms
• Duplicate per scan (copy from L2A)
• Read, interpret, and include in your quality
  flags
• Updates to include these flags are welcome at any
  time