The Challenges of Weather Prediction for Agriculture: From Weather Rocks to Supercomputers

1. The Challenges of Weather Prediction for Agriculture: From Weather Rocks to Supercomputers Leon F. Osborne, Jr. Chester Fritz Distinguished Professor of Atmosphere Sciences University of North Dakota President Meridian Environmental Technology, Inc. Grand Forks, North Dakota National Farm Business Management Conference Fargo, North Dakota June 14, 2010

2. Perceptions & Attitudes Towards Weather & Weather Forecasting • “Weather: Everyone talks about the weather but no one ever does anything about it!” • “Weather Forecasting: . . . • where you can always be wrong and still have a job!!”

3. Ag Weather Challenges

4. The Weather Challenge:Providing reliable, timely and accurate weather and climate information to support agricultural decision-making that meets producer expectations

5. Defining Realistic Expectations • Mitigation of weather impacts on crop productivity drives the need for reliable weather information • Expectations are that information will be clearly stated, easily understood, and accurate

6. Ag Producer Challenge • Knowing what constitutes a realistic expectation of accuracy in spatial and temporal extents • How? • Understanding factors associated with defining weather and climate conditions • Awareness of forecasting limitations • Seeking out proven and trusted sources of information

7. What is ‘Risk Management’ • Definition: “Protection of life, property, and economic assets through threat minimization” • Relationship to weather: The understanding of future conditions dictated by variations in global weather patterns • Dominant Weather Sources Available: • Federal government & university services • Private-sector Tailored Weather Services

8. Major Weather & Climate Factors • Extraterrestrial forcing • Land surface variations • Ocean storage and transport

9. Latitude Elevation Water resources Ocean currents Topography Vegetation Prevailing wind currents Weather & Climate is the Interaction of the Earth and Its Atmosphere to Sunshine

10. Weather & Climate Starts with the Sun • The Earth’s surface, clouds, and the moisture in the atmosphere permits the solar radiation to warm the atmosphere

11. The surface temperature of the Earth has increased, particularly over the past 100 years. from IPPC2001

12. Sept. 2001 Nov. 10, 2009 Solar Cycles and Sunspots • Occur in 11-year cycles • 2009-10 sunspot minimum • Most dramatic in 50 years • Promoted cooler 2009 summer conditions 5 Jan 2010 10 Feb 2010

13. 2009 Sunspots Minima Over Past Century Is this a noticeable impact on our annual weather?

14. Sunspots and Solar Irradiance • Lower number of sunspots over time represents less solar output and less warming of the Earth

15. El Nino Southern Oscillation (ENSO) • Sea surface temperature variation • Leads to alteration in atmospheric circulations • Alters from warm to cold • Cycle of 2 to 7 years • El Nino (warm) & La Nina (cold) • Impacts vary • Primary direct precipitation and temperature impact on Northern Plains in winter • Indirect (and most significant) impact is influence on jet stream flow (storm track) El Nino La Nina

16. Short-Term Climate & Weather: All About the Jet Stream Pattern Split Jet Stream Pattern

17. Global Circulation Centers • Semi-Permanent features that respond to long-term solar and terrestrial forcing • Annual positioning determines seasonal weather conditions • Example - Bermuda High • Dictates moisture flow in summer east of Rockies • Responds to ocean temperatures & temperature variations between pole and equator

18. ‘Storm Track’ is related to the Orientation of the Jet Streams • Position and orientation controls short-term to seasonal . . . • Temperature • Precipitation Cold & Wet L ‘Warm’ & Dry Cool & Wet

19. Global Weather / Climate Patterns Dictate Soil Moisture Availability • Distribution of wet and dry conditions depend upon global weather conditions and/or long-term climatic conditions

20. DailyWeather Conditions • Surface conditions depend upon upper-level wind currents • Jet stream orientation defines weather patterns L

21. Making of a Weather Forecasts • Data from the . . . • Atmosphere • Ocean • Land • Proper combination of data • Use of computer models • Generation of user information

22. Weather Data

23. Weather Satellite Constitutes ~ 96% of data used for weather computer models

24. Weather Radar • Detects precipitation-size particles in clouds • Amount of radar transmitted microwave radiation reflected back provides indication of particle size and concentration Detected Weather Radar Beam Undetected Weather Weather Radar 4-18

25. Weather Radar • Readily available to the public as images • Often misinterpreted by the untrained user!! • Raw data used within weather models

26. Forecasts every mile Combination of Heterogeneous Data Fields Mapping of Solution onto Geographic Framework Satellite Data Weather Radar Data Atmospheric Winds Atmospheric Thermal Structure Surface Conditions Result of Parameter Integration is Joined with a Geospatial Domain to Produce Information for Distribution = Three-Dimensional Data Assimilation

27. Z V S X A W R C U Q T Tf Improved Weather Prediction Models • Models the atmosphere and land surface in terms of mathematical physics • Utilizes high-speed computing to generate 100s of ‘possible realities’ that can be statistically combined to produce a better ‘estimate’ as to which prediction is correct

28. Weather Information at Specific Locations • Weather Information Content • Precipitation (Type, Rate, Amount) • Wind Speed & Direction • Temperature • Sunshine Amount / Cloud Cover • Multi-Depth Soil Temperature • Multi-Depth Soil Moisture Content • Leaf Wetness

29. Data …Achilles Heel of Weather Forecasting • Only 60 years of 3-D global weather analyses • 1948-2007 • ~50 years of global sea-surface temperatures • Limited accurate global atmospheric observations • U.S. - 1221 stations with data since 1900 • > 75% of globe has less than 75 years of continuous weather observations • Even today only limited observations are collected from 10-meters to 1,000 meters above the Earth • The most crucial region to understanding the relationship between the Earth and atmosphere • Diminishes ability to provide accurate agricultural weather forecasts!!

30. Accuracy versus Predictability • The closer in time of an event the more likely accuracy will be higher • The use of longer timeframe prediction is subject to the amount of “risk” one is willing to accept

31. Use of Weather Predictions • Weather predictions are unregulated and can be provided by trained and un-trained individuals • Important to understand the difference between a weathercaster and a meteorologist (or atmospheric scientist) • No weather prediction system is perfect and likely never will be • The accuracy and skill of the prediction will always diminish the further into the future the prediction

32. Varieties of Weather Predictions And Their Risk (Accuracy) • Short-Range Weather Forecasts (0 - 10 Days) • Highest level of accuracy (lowest risk) … Typical Accuracy > 85% • Deterministic forecasts based upon physical models of the atmosphere • 30-Day Forecast Maps • Accuracy varies by season and locale with greatest accuracy along coastal regions … Typical Accuracy > 75% • Combination of deterministic and statistical models of the atmosphere • Climate (Seasonal) Outlooks • Compilations of recent historical data, climate statistics and forecast verifications … Typical Accuracy > 60% • Statistical models comparing past patterns with global weather circulation projections

33. Expected 2010 Weather • El Nino conditions of 2009-10 winter shifting to La Nina conditions for second half of 2010 • Cooler conditions across Great Basin through Northern Plains • Wet conditions from Intermountain West through the Central Plains and Midwest • Hot conditions from Kansas to North Carolina • Dry conditions along Gulf Coast States

34. Drought Outlook

35. 2010 Weather Expectations Above Normal Precipitation Below Normal Temperatures Above Normal Precipitation Above Normal Temperatures Near Normal Precipitation Above Normal Temperatures Below Normal Precipitation Early to Mid Summer 2010

36. 2010 Weather Expectations Near Normal Precipitation Below Normal Precipitation Below Normal Precipitation Near Normal Temperatures Below Normal Precipitation Above Normal Temperatures Above Normal Temperatures Mid-Summer to Mid-Fall 2010

37. Thank You! Contact Information: leono@meridian-enviro.com www.meridian-enviro.com 701-792-1800