DEVELOPMENT OF A NEW LETTUCE ICE FORECAST SYSTEM FOR YUMA COUNTY

1. Paul Brown Mike Leuthold University of Arizona DEVELOPMENT OF A NEW LETTUCE ICE FORECAST SYSTEM FOR YUMA COUNTY

2. BRIEF HISTORY • Original Lettuce Ice Forecast Program • National Weather Service (NWS) • Issue Through ~1997 • NWS Reorganization (1996-97) • Closed Yuma Office & Ended NWS Ag Forecasts • Grower Interest • Request to Reestablish Program • Request to NWS for Yuma Model • “Search” of Yuma Office Records • No Model Located • About 9-11

3. HISTORY CONTINUED • AZMET Seminar • U of A Atmospheric Science Dept. • High Resolution Forecast Model • Interested In Agriculture Forecasts • USDA Specialty Crops Grant • Develop Lettuce Ice Forecast System • Using High Resolution Forecast Model • Project Funded & Initiated in Oct. 2010

4. PROGRAM GOALS Provide high resolution temperature and ice forecasts for lettuce producers in Yuma Co. Collect field data consisting of temperature, humidity and wind speed at shelter level, and temperature and leaf moisture at lettuce level to both improve and validate the accuracy of forecasts.

5. WEATHER MODELS Used To Forecast Development & Movement of the Atmosphere Wednesday @ 5pm Thursday @ 5pm

6. ANATOMY OF A WEATHER MODEL Earth Surface is Divided Into Segments or Grids. Atmosphere Above Each Grid Area Is Then Layered. Observational Data Are Used To Estimate Conditions At Each Grid Point. Model Uses Complex Mathematics Determine How Atmosphere Will Evolve.

7. WEATHER RESEARCH & FORECAST (WRF) MODEL This model is presently used by NWS to forecast weather for the region shown above. The model divides the atmosphere into 60 layers, operates on a 12 km (6.2 mile) grid spacing and forecast out to 84 hours (3.5 days).

8. UNIVERSITY OF ARIZONA MODIFICATIONS TO WRF MODEL • Model Core Adjusted For AZ Conditions • Atmosphere • Clouds • Precipitation • Much Higher Resolution • 1.5 km (0.9 miles) • Handles Complex Topography Better • Better Land Surface Characterization

9. GRID SPACING/RESOLUTION Current NWS Models Large Grid Spacing Grid-Wide Topography, Land Use & Initial Conditions Model Generates Forecast for Grid Region

10. GRID SPACING/RESOLUTION UA WRF Models Smaller Grid Spacing Better Separation of Land Characteristics Improved Assessment of Topography & Air Drainage

11. PROJECT SCHEMATIC Provide Accurate High Resolution Winter Temperature Forecasts WRF MODEL COMPUTER MONITORING REFINEMENT Initialize Model Generate Forecast Ground Truth Adjust Model Repeat Process

12. PROJECT TIMELINE YEAR 1 • Set Up Model for Yuma Co. • Prototype Forecasts • Install Monitoring Equip. • Refine Forecast Model YEAR 2 • Operational Forecasts • Continue Monitoring • Validate Model Accuracy YEAR 3 • Operational Forecasts • Industry Funded • Part of AZMET

13. PROJECT STATUS • Forecast Model • Functional & Available Via Web • Graphic Forecasts • Text Forecasts • Working on Adjustments • Monitoring Systems • Functional & Available Via Web • Graphical Summaries • Text Summaries • Raw Data

14. GRAPHIC FORECASTS • Graphic Forecasts For Next 48 Hours • Hourly Maps Providing… • Temperature @ Shelter Height (2m or 6.5’) • Dew Point @ Shelter Height • Wind Speed & Direction • Hourly Maps Providing • Surface Temperature (Crop Level)

15. SHELTER & “SURFACE” LEVELS Shelter Height (2m or 6’5”) Lettuce Height (30 cm or 1’)

16. GRAPHIC FORECAST Shelter Conditions • Elevation • Roads • Urban Area • Weather • Temperature • Color • Text • Dew Point • Wind Conditions Shelter Conditions At 6 a.m. on March 9

17. GRAPHIC FORECASTS Shelter Conditions Shelter Conditions At 8 p.m. on March 9

18. GRAPHIC FORECASTS Surface Temperatures Forecast for 6 a.m. on March 10th

19. TEXT FORECASTS • Text Forecasts For Next 48 Hours • Maximum & Minimum Tempertures • Quantitative Precipitation • Hourly Forecasts Of… • Shelter Temperature • Dew Point

20. WEATHER & PRECIPITATION FORECAST Quantitative Precipitation Forecasts Amounts Rather Than Probability

21. HOURLY FORECASTS (TEXT) Shelter Temperature, Surface Temperature & Dew Point Tomorrow Shelter: 45F Tomorrow Surface: 40F Day 2 Shelter: 45F Day 2 Surface: 40F

22. INTERNET ACCESS http://www.atmo.arizona.edu/index.php?section=weather&id=wrf

23. CLICK

25. INITIALIZATION

26. LOCAL MONITORING Model Improvement/Validation • Roll • Dome Valley • US95 & 5E • Yuma Ag Ctr • 14th & G • 18th & F3/4 • AZMET • Yuma Valley • Yuma South • Yuma N. Gila • Roll

27. MONITORING SYSTEMS Temperature Humidity Wind Speed Temperature Leaf Wetness

28. INTERNET ACCESS http://ag.arizona.edu/azmet/ls.htm

29. MONITORING DATA Graphical Output Update Each Hour Temperature, Dew Point and Wind Speed @ Shelter Height Lettuce Level Temperature, & Dew Point Leaf Wetness

30. MONITORING DATA Text Output Updated Each Hour

31. INTERNET ACCESS Raw Data Available For Use/Analysis

32. RESEARCH CHALLENGES Model Forecast: 16 m Heat Wind Radiation Condensation ?? Lettuce Level 0.3 m Soil Type, Soil Moisture, Vegetation Heat

33. INTERATIVE PROCESS WRF MODEL COMPUTER MONITORING REFINEMENT Initialize Model Generate Forecast Ground Truth Adjust Model Repeat Process

34. COLDEST TEMPERATURES

35. EXPANSION OF MONITORING • Acceptable Within Limits • Strategic: Forecast Improvement • Costs Must Be Covered • Equipment • Operations

36. GROWER MEETINGS • Feedback on Forecasts/Program • Forecast & Website Training • Expansion of Monitoring Program • Alternate Delivery Systems • Text Msgs • Twitter • Facebook

37. QUESTIONS???