The Colorado Climate Center at CSU. residents of the state through its threefold

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1 The CoAgMet Network: Overview History and How It Overview, Works N l Doesken Nolan D k and d Wendy W d Ryan R Colorado Climate Center Colorado State University

2 First -- A short background In 1973 the federal government abolished the State Climatologist program nationwide leaving Colorado without Later that same year, Colorado re-established established the State Climate program with support through the Colorado Agricultural Experiment Station at Colorado State University.

3 Our Mission The Colorado Climate Center at CSU provides valuable climate expertise to the residents of the state through its threefold program of: 1) Climate Monitoring (data acquisition, analysis, and archiving), 2) Climate Research 3) Climate Services.(providing data, analysis, climate education and outreach)

4 Monitoring our Climate Elements: temperature, precipitation, snow, wind, solar, evaporation, soil temperatures, humidity, clouds, etc. Fort Collins CSU Historic Weather Station Continuous monitoring since the 1880s

5 Vail Mountain Snotel

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9 Montrose Annual Precipitation ( )

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12 CoAgMet = Colorado Agricultural Meteorological Network

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14 History of CoAgMet In the early 1990 s, CSU extension plant pathologists and USDA Ag. Research Service scientists decided to collaborate efforts to collect agricultural weather data. Standard automated instruments and data collection platforms were selected and a small network of stations was deployed in fully irrigated agriculture. As the network grew, the Colorado Climate Center became increasingly interested in using the data, began daily data collection, quality control and built a web interface to distribute data and products to users across the state.

15 CoAgMet 1992

16 CoAgMet 1997

17 CoAgMet 2002

18 CoAgMet Today

19 Overview Currently there are 65 stations Data are collected on hourly and daily time steps and include: temperature, humidity, solar radiation, wind speed and direction, and soil temperatures. Data and graphics are available online: ccc.atmos.colostate.edu/~coagmet t t coagmet

20 What do the stations measure?

21 Cup anemometer and wind vane: Wind speed, direction and gusts 2 m Above all else facing South Pyranometer: Solar radiation Temperature/Humidity sensor in radiation shield Solar panel powers the station 2 m 1-3 m Tipping bucket rain gage Data collection platform (DCP) -5/-15 cm Soil temperatures

22 Data Collection Platform Power supply Datalogger Communications device (cellular modem) Incoming sensor cables

23 Why these measurements? The main goal of CoAgMet is to calculate evapotranspiration (ET) from meteorological measurements. Several models exist that vary by input data and complexity: Penman-Monteith physically based Kimberly-Penman physically based Hargreaves empirical temperature based Standardized ASCE Equation attempts to standardize calculations to make them more comparable The standard d CoAgMet station collects the elements needed to calculate evapotranspiration.

24 Temperature/Humidity Temperature: During the growing season, higher temperatures during daylight hours cause the plant stomata to open more resulting in greater transpiration. Humidity: The higher the humidity the less transpiration will occur (more transpiration occurs in dryer air)

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26 Wind Movement As air movement across plant canopies increase, higher transpiration rates occur as the saturated air (from transpiration) ti around the plant is mixed with and replaced by and dryer air.

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28 Solar Radiation Alfalfa only reflects about 25% of incoming solar energy which leaves ample solar energy to drive ET rates. ET trends follow a similar pattern as seasonal solar radiation and air temperature.

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30 Precipitation Precipitation data are not used explicitly in the ET equations, but precipitation data are essential in determining crop water needs Monitoring precipitation also provides an idea of soil moisture availability at the station.

31 Soil Temperatures Having the temperature of the soil aids in knowing when the soil has warmed enough to plant. Soil temperature also gives an indication of the amount of ground cover at the station.

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33 CoAgMet example ET Data Growing season Alfalfa reference ET for 2011 growing season comparing an unirrigated site near Delta to a partially irrigated site near Olathe

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35 Please note: CoAgMet instrumentation are high quailty and the CoAgMet data are easily accessibly..... However

36 Problems with CoAgMet Missing data Site exposure Routine maintenance

37 Missing/Questionable Data Due to various problems that occur to remote weather stations, missing data causes problems for users. Battery failure and communications problems are the most common. Even if the whole station doesn t fail, sensors go bad and can leave some elements missing until the station is serviced.

38 Unfortunately, data are not complete at all stations Peckham, Mean Monthly Wind Run (May Sept) p) Missing Data Mean Wind Run (m mi) March April May June July August September October Month

39 Some Data are Questionable CSU Fruita Experimental Station, Monthly Vapor Pressure ( ) Vapor Pressure ( mb) Vapor Pressure (mb) March April May June July August September October Month Lamar 01, Mean Monthly Vapor Pressure ( ) Mean Mean Solar Radiation (Lgly) Avondale, Mean Monthly Solar Radiation ( ) March April May June July August September October Month Mean March April May June July August September October Month

40 Site Exposure One of the assumptions s of the evapotranspiration a at o equations is that water is not limited (i.e. in full irrigation). Some stations are not located in ideal reference conditions. Some stations have obstructions (buildings/crops) that affect the amount of wind in certain directions. The exposure of the site can have an impact on the data and over/under estimate reference ET.

41 Siting and Exposure The Good and the Not so Good FTC01 Fort Collins AERC has appropriate p citing for reference ET calculations HOT01 Hotchkiss is not ideally cited for reference ET calculations

42 Routine Maintenance Due to the fact that CoAgMet is run by collaborations and operates on a limited budget, routine maintenance is difficult with such a large network. There is no full time CoAgMet technician. Our goal is to visit each station once a year to make sure the station is operating properly. Sensor are swapped out once every 2 years. Data users should be cautious and thoroughly quality control the data they are using.

43 Possible Solutions? Efforts are being made to fill in missing data using relationships with nearby stations. This data would be flagged when presented on the website. Our website now color codes stations according to their irrigation are classified as: full irrigation, partial irrigation and dryland. Making this information available to the public allows them to know more about their data source.

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45 Possible Solutions? We do our best with limited funds to keep a maintenance schedule but it is very difficult. If we are not able to keep high standards for our weather stations, some current stations may need to be discontinued in the near future.

46 CoAgMet Website Demonstration

47 The Colorado Climate Center Home Page

48 Hourly Climate Data Plots Click Here

49 Hourly Climate Data Plots Temperature GLY03 Greely June 9, 2007 through h June 15, 2007 Relative Humidity

50 Click Here Daily Climatic Summary

51 Daily Climatic Summary

52 Monthly Station Summaries Click Here

53 Monthly Station Summaries KSY01 Kersey Aug. 2007

54 Daily Regional Climatic and ET Comparison Click Here

55 Daily Regional Climatic and ET Comparison North Central Region, May 30, 2007

56 Click Here Crop Specific ET Reports

57 Crop Specific ET Reports Calculates multi-day ET for: alfalfa, corn, dry beans, small grain, sugar beets, potatoes, t onion, winter wheat, turf grass, and reference ET, via Penman-Monteith or Kimberly-Penman

58 CoAgMet web access: