Level 1 Product Assessment of NPP VIIRS

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Level 1 Product Assessment of NPP VIIRS 

• Paul Menzel (PI)
• Chris Moeller (Co-I)
• Dan LaPorte
• Univ. Wisconsin
• NPP Science Team Kickoff mtg
• Nov 4-6, 2003 

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Level 1 Product Assessment of NPP VIIRS EDR/CDR
List

•      Primary focus on Level 1 data RDR/SDR
• TEB radiances
• RSB radiances/reflectances
• Performance evaluation
• Spectral characterization influence
• Detector and mirror side striping
• Crosstalk assessment in various forms
• EDR/CDR focus to evaluate importance of Level 1
  performance issues, e.g.
• Imagery
• Cloud Mask (intermediate product)
• Cloud Cover (including cloud phase)
• SST

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Level 1 Product Assessment of NPP VIIRS Role of
PI, Co-I

• Paul Menzel (PI), Chris Moeller (Co-I), Dan
  LaPorte
• Menzel, Moeller collaborate on strategy.
• Moeller Test data set and forward model
  analysis, influence on science products, L1B
  cal/val.
• LaPorte Test data set acquisition/analysis/strate
  gy. On-site presence desired during prelaunch
  testing.
• Strengths Sensor design/testing (LaPorte)
• TEB calibration (Menzel, Moeller)
  Product validation (Moeller)
• All participated in MODIS pre postlaunch
  evaluation.
• Close working relationship with MCST

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Level 1 Product Assessment of NPP VIIRS Approach

• Prelaunch
• Review/analyze test data sets to evaluate
  quality/information content, esp. when
  performance anomalies are uncovered.
• Simulate EDRs primarily with aircraft data to
  evaluate impact of SDR performance.
• Create forward model simulations to investigate
  radiometric impact of anomalous performance in
  TEB bands.
• Build corporate knowledge applicable to on-orbit
  performance investigations.
• Postlaunch
• Review on-orbit data sets for performance
  anomalies. Propose/generate correction algorithms
  when useful.
• Conduct field campaigns for L1B validation using
  aircraft-based observations. Comparisons with
  existing on-orbit sensors (e.g. MODIS, GOES)

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Level 1 Product Assessment of NPP VIIRS
Baja
11um
14.3um
Pre launch correction
Terra Experience
A known optical leak at 11um caused the image of
the earths surface (in this case, Baja
peninsula) to be present in MODIS 14.3um data.
Through testing, the pre-launch correction
coefficients were revised, removing the
contamination.
14.3um
Post launch correction
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Cirrus Detection in MODIS Band 26 Corrected
Reflectances
MODIS global thin cirrus detection has been
constrained by detector striping and out-of-band
signal from the surface of the earth in Band 26
(1.38 um). A correction procedure has been
implemented at the Univ. Wisconsin to remove
contamination in the data, allowing thin cirrus
with optical depth as low as 0.1 to be detected
in the MODIS Cloud Mask.
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MODIS Emissive Band L1B Cal/Val from ER-2
Platform

• Underfly Terra and Aqua with ER-2
• Compare MODIS with MAS and S-HIS
• SAFARI-2000, TX-2001, TX-2002

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Level 1 Product Assessment of NPP VIIRS
Resources and Contributions

• Sensor characterization data set evaluation (e.g.
  spectral knowledge, crosstalk impact).
• Forward model based sensitivity studies for
  insight into performance issues in SDR.
• Close relationship with NCST
• Contributions towards Cal/Val Plan and reports on
  RDR/SDR performance.

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Level 1 Product Assessment of NPP VIIRS
Resources and Contributions

• Questions/thoughts
• How does NPPST impact/influence/monitor prelaunch
  test data set progress/plan?
• How do validation findings evolve into
  operational algorithm improvements?