1 / 23

Alberta Agriculture and Food (AF)

Alberta Agriculture and Food (AF). Surface Meteorological Stations and Data Quality Control Procedures. Presentation Overview. Existing and proposed (AF) network Data QA/QC Parameter list Quality states QA/QC checks Data filling Conclusions. Meteorological Station Expansion.

kaili
Download Presentation

Alberta Agriculture and Food (AF)

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Alberta Agriculture and Food (AF) Surface Meteorological Stations and Data Quality Control Procedures

  2. Presentation Overview • Existing and proposed (AF) network • Data QA/QC • Parameter list • Quality states • QA/QC checks • Data filling • Conclusions

  3. Meteorological Station Expansion • 67 N-R-T scalable station platforms • ►all season ppt (GEONOR)►temperature ►humidity • ► GOES platform ► 2M wind speed • ► Campbell Cr10x-2m loggers • Additional sensors can be added later • Data will be freely accessible and sensors can be added by any one with dollars, with the caveat that all data would be public domain. • Currently 44 are installed and operational • 23 more will be operational by May 1, 2008

  4. AF Stations:(N = 113) • Common Elements • ►All season ppt (GEONOR) ►Temperature ►Humidity • ►Wind speed 2 m ►GOES platform ► Campbell Cr10x-2m loggers • 36 Drought Net Stations (AGDM) • Incoming short-wave solar radiation (26) • Net solar radiation (3) • Wind speed and direction at 10 m (36) • Soil moisture and temperature at 5, 20, 50, 100 cm (30) • 10 IMCIN Stations • Incoming short-wave solar radiation (10) • Wind speed and direction at 10 m (10) • 67 Agriculture Climate Monitoring Stations (AGCM) • Wind direction at 2m (15) • Incoming Short-wave solar radiation(15)

  5. ACGM (AF) IMCIN (AF) Other (AENV AES SRD) Existing and proposed stations in Alberta’s Near-Real-Time Network AGDM (AF) 20 km buffer

  6. A QA/QC and Data-Filling Decision Support System forNear Real-Time Climate Data Providing computer-assisted quality assurance, quality control and data filling

  7. Parameter List (Hourly) • Temperature • Humidity • Solar Radiation • Wind Speed • Wind Direction • Precipitation (hourly and 6 hourly) • Soil Moisture • Soil Temperature

  8. Quality States • Valid • Not needed to be checked by a human • Suspect • Needs to be checked by a human and validated or filled • Invalid • Needs to be checked by a human and filled • Missing • Needs to be checked by a human and filled

  9. QA/QC Checks • Range • within a reasonable range • Step • maximum allowable change • Persistence • minimum allowable change • Like Sensor • similar value to similar sensors • Spatial • similar value to neighboring stations (parameter dependent)

  10. Methodology for Defining QA/QC checks • We used the hourly period of record supplied by Environment Canada that contains >25 million records from 250 stations in and around Alberta • An adjustable trigger point for the “suspect” occurrences was set at 0.01% (1:10,000) for each test • Arbitrary and adjustable (default or station specific) • For 200 stations examine @ 50hourly values per day

  11. Range Checks • Three range checks • Valid • Suspect • Invalid • If the data falls within the inner range then it will be marked Valid If it falls in between the outer range and the inner range it will be marked Suspect • If data falls outside the outer range it will be marked as Invalid • If the data is missing it will be marked Missingand then filled

  12. Range Checks:Solar Radiation Invalid Suspect Valid -0 950 Hourly Solar Radiation (W m-2)

  13. Range Checks:Temperature:

  14. Data Filling • Temporal filling • Spatial filling (IDW) • Spatial-temporal filling (IDW+) • Manual filling In every parameter’s daily rollup you know how many records were filled so you can judge the validity of the daily value

  15. Conclusions • Relatively dense high quality and scalable network in the Agricultural area of Alberta • We have a state of the art QA/QC process that is both flexible and data driven • Reduces man power • Capable of generating error logs for maintenance checks

  16. valid valid susp. susp. valid Persistence Check Difference of Maximum and Minimum over n steps must be greater than y susp. Persistance Checks

  17. valid Step Difference of maximum and minimum over n steps must be at most y susp. valid valid valid valid Step Checks

  18. Other Tests • Like Sensors • Relating wind speed 2M to wind speed 10M • Relating occurrence of precipitation to humidity • Nearest Neighbors

  19. M M M M Temporal Filling:for most parameters One value missing either side Simply average of two values adjacent values Up to X values missing linearly interpolate missing values from valid end points Missing or Invalid If more than X consecutive values are missing use spatial interpolation • 3 for most parameters • 6 for Soil Temperature • 12 for Soil Moisture Data Filling

  20. Spatial filling:Inverse Distance Weighting • Adjustable parameter dependent radius • Max 8 neighbors • Rainfall = 70 km radius • Other = 120 km radius • Else use nearest station if within X radius • Else use nearest station and mark as suspect Data Filling

  21. Distribution of total ppt. by day at nearest station 0.44*16.4 0.35*16.4 0.21*16.4 Estimated ppt at Barnwell Spatial-Temporal Filling:Precipitation Total ppt. at Barnwell using IDW = 16.4 Data Filling

More Related