AMSRE Team Leader Science Computing Facility

1
AMSR-E Team Leader Science Computing Facility
2
AMSR-E TLSCF

• Science Software Status
• New Sea Ice Drift Product
• Quality Flags

3
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. The low glint angles correlate
  well with the recent observed RFI artifacts. Over
  oceans, RFI can be intense 50 K for 18.7V, and
  100 K for 18.7H. Cases this large correspond to
  low wind conditions with very smooth seas.
  Initial analysis over land did not reveal
  significant RFI impacts. The affected period for
  this RFI is from July, 2007 forward.

4
AMSR-E Science Software Status

• L2B Ocean V06
• October 2007
• Last algorithm updates version V05, April 2007
• 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

5
AMSR-E Science Software Status

• L2B Rain V10
• October 2007
• First Linux version
• No algorithm changes
• Significant algorithm update expected in December
  2009
• L3 Sea Ice V09
• September 2008
• Promote the product maturity status to Validated

6
AMSR-E Science Software Status

• L3 Sea Ice V10
• January 2009
• Add multiyear sea ice mask to the snow depth
  product
• Modify the tie point tables for the Antarctic to
  match those of the Arctic
• Resulted in significant Antarctic changes (Walt
  Meier, NSIDC)
• L3 Sea Ice V11
• June 2009
• Correct an error in the snow depth over ice
  retrieval in the Southern Hemisphere. This error,
  introduced in V10, caused snow depth to be
  overestimated by a factor of about two.

7
AMSR-E Science Software Status

• L3 Ocean V03
• November 2007
• Updates expected (due to RFI)
• 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

8
AMSR-E Science Software Status

• L3 Snow T08
• July 2008
• Promote the product maturity status to
  Transitional
• L3 Snow V09
• December 2008
• Promote the product maturity status to Validated
• Modify ancillary file format
• Last algorithm update version B07, April 2006

9
AMSR-E Science Software Status

• L3 Rain V06
• April 2008
• Promote the product maturity status to Validated
• Skip duplicate (overlapping) scans in consecutive
  L2A files
• 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

10
AMSR-E Science Software Status
11
New AMSR-E Product

• L3 Sea Ice Drift
• B01
• Current code received at TLSCF May 2008
• Initial code received in March 2008
• Returned due to various issues
• 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

12
AMSR-E L2A Quality Flags
13
AMSR-E L2A Quality Flags

• Recent user question concerning L2B Rain product
• April 2, 2009 descending orbit (AMSR_E_L2_Rain_V10
  _200904021441_D.hdf)
• Geolocation issue in the middle of an orbit
• User asked if there was a flag in the data that
  would indicate what the issue was
• TLSCF confirmed the problem was due to a maneuver
• There is a flag set in the L2A data that could be
  used by the L2B and L3 algorithms that would have
  given the user this information
• In fact, there are 3 flags set in the L2A files
  that could be useful to the L2B and L3 algorithms

14
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.

15
AMSR-E L2A Scan Quality Flag
16
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

17
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