Clarus Quality Checking

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Clarus Quality Checking
Kevin R. Petty National Center for Atmospheric
Research ICC 4 Falls Church, Virginia August
8, 2006
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Clarus Quality Checking

• GOALS
• Document the scientific merit of the proposed QCh
  tests
• Identify Gaps in current Algorithms
• Propose supplemental QCh processes that would
  improve the QCh service
• Recommend the most robust combination of QCh
  tests for the Clarus system

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Clarus Quality Checking Proposed Algorithms

• Nine QCh procedures being implemented as part of
  the Clarus Proof of Concept
• Manually Change QCh Flag
• Sensor Range Test
• Climate Test
• Barnes Spatial Test
• Step Test
• Persistence Test
• Like Instrument Test
• Dew Point Temperature Test
• Sea Level Pressure Test

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Clarus Quality Checking Proposed Algorithms

• Seven supplemental QCh algorithms that were
  included in the Clarus Detailed Requirements
  Document
• Optimal Interpolation Spatial Test
• Potential Temperature Test
• Theoretical Solar Radiation Test
• Precipitation Amount Test
• Wind Direction Test
• Soil Moisture Change Test
• Soil Moisture Freeze Test

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Clarus Quality Checking Scientific Merit

• Algorithms have be used for decades
• Proven
• Fast and efficient
• Original constraints/limitations have changed
• Spatial distribution of data
• Computational power
• Data types
• Data availability and acquisition

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Clarus Quality Checking Gaps

• Topographic Features
• Mountains
• Coastal Areas
• Oceans
• Lakes
• Rivers
• Data sparse regions
• Beyond state variables (e.g. precipitation, cloud
  cover)
• Low temporal resolution data
• Mobile data

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Clarus Quality Checking Supplemental Algorithms

• Algorithms based on ancillary data
• Radar (NEXRAD, TDWR, ARSs, Etc.)
• Satellite (GOES, A-TRAIN CONST., Etc.)
• Cameras
• Cosmic
• Numerical Model
• Fuzzy Logic based algorithms
• Alleviate the need to threshold
• Ability to provide one flag
• Computationally efficient

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Clarus Quality Checking
User Perspectives

• Diverse End User Community
• Data Contributors
• Academic Institutions
• State, County, Local Maintenance Managers
• Traffic Operations Center
• Transit
• Emergency Managers
• Etc.
• Diverse Requirements