1. Weather Station Data Quality and Interpolation Issues in Modeling Joe Russo International Workshop on Plant Epidemiology Surveillance for the Pest Forecasting Postgraduate Unit of the Autonomous University of San Luis Potosi San Luis Potosi, Mexico May 22, 2008

2. Data as the Basis for Modeling Activity Data Models Integration Interpretation Dissemination

3. Weather Data Sources Standard or Point Observations Remote Sensing Grid Archive Standard or Point Observations Remote Sensing Grid Archive

4. Weather Data Sources Standard or Point Observations Synoptic Weather Observations –Primary Use is Meteorology –Reporting Interval Generally 3 or 6 Hours –Variation in Regional Reporting Practices Metar Weather Observations –Primary Use is Aviation –Reporting Interval Generally One Hour –Precipitation Amounts for U.S. Only Other Government Networks Private Networks

5. Weather Data Sources

6. South America Synoptic Reports 12:00Z

7. Weather Data Sources

8. South America Metar Reports 12:00Z

9. Weather Data Sources Remote Sensing Radar Satellite Other (not operational)

10. Weather Data Sources NexRad Precipitation Estimates

11. Weather Data Sources NexRad Precipitation Estimates

12. Weather Data Sources Satellite Precipitation Estimates

13. Weather Data Sources Grid Radar Satellite Other (not operational)

14. Weather Data Sources Global Forecast System Analysis (Model)

15. Weather Data Sources Grid Versus Station Points

16. Historical Records –100 years of monthly observations –100 years of daily observations –100 years of hourly observations for select locations –Temperature, precipitation, dewpoint, wind speed, wind direction, cloud cover … –3-4 years NEXRAD online / 8 years available Source Types Weather Data Sources Archive NARRGSOD/NCDCSODCSODISH Global Reanalysis IPCCGHCNNCDCUCAR

17. Weather Data Processing Quality Assurance Quality Control Professional Inspection Replacement of Data Quality Assurance Quality Control Professional Inspection Replacement of Data

18. Pass or Fail Multiple Tests –Plausibility –Climate –Spatial Near-Neighbor –Temporal Inconsistency Weather Data Processing Quality Control

19. Statistical Combinatio n Climate - Compares observations to the envelope of climate Weather Data Processing Quality Control

20. Spatial Near-Neighbor - Compares observations to surrounding stations Weather Data Processing Quality Control

21. Spatial Near-Neighbor - Compares observations to surrounding stations

22. Temporal Inconsistency – Lack of variability relative to history Weather Data Processing Quality Control

23. Temporal Anomaly – Suspicious extreme value relative to history Weather Data Processing Professional Inspection

24. Weather Data Processing Replacement of Data Consensus of quality control tests to determine erroneous datum Analytic methods are used to correct erroneous datum –Interpolation –Correlation –Model correction –Climatology Statistical combination to compute most- likely value

25. Local Models and/or Interpretation Mesoscale Models and/or Integration of Surface Features Mesoscale/Large –Scale Models Weather Modeling Question of Scale

26. Interpolated Grid Values Using Station Data

27. Copyright (c) 2008 ZedX, Inc. Interpolated Grid Values Using Station Data

28. Copyright (c) 2008 ZedX, Inc. Interpolated Grid Values Using Station Data

29. Copyright (c) 2008 ZedX, Inc. Interpolated Grid Values Using Station Data

30. Copyright (c) 2008 ZedX, Inc. Interpolated Grid Values Using Station Data

31. Thank You! Questions?