• Andresen, J. A., , and Nurnberger F. V. , 1997: A field comparison of operational temperature sensors. Preprints, 10th Conf. on Applied Climatology, Reno, NV, Amer. Meteor. Soc., 157–160.

    • Search Google Scholar
    • Export Citation
  • ASOS Program Office, 1992: Automated surface observing system site technical manual S100. AAI Systems Management Incorporated.

  • Blackburn, T. M., 1993: Effects on climate change resulting from changes in National Weather Service cooperative station instrumentation and siting conditions. Preprints, Eighth Symp. on Meteorological Observations and Instrumentation, Anaheim, CA, Amer. Meteor. Soc., J6–J11.

    • Search Google Scholar
    • Export Citation
  • Bradley, J. F., 1994: Interim results of the climatic temperature study. U.S. Department of Commerce Misc. Rep., NOAA/NWS Test and Evaluation Division, 20 pp.

    • Search Google Scholar
    • Export Citation
  • Bradley, J. T., , and Bradley J. F. , 1995: CRS-MMTS temperature comparison study. U.S. Department of Commerce Misc. Rep., NOAA/NWS Test and Evaluation Division, 20 pp.

    • Search Google Scholar
    • Export Citation
  • Brock, F. V., , Richardson J. , , and Semmer S. R. , 1995a: Passive multiplate solar radiation shields. Preprints, Ninth Symp. on Meteorological Observations and Instrumentation, Charlotte, NC, Amer. Meteor. Soc., 329–334.

    • Search Google Scholar
    • Export Citation
  • Brock, F. V., , Semmer S. R. , , and Jirak C. , 1995b: Passive solar radiation shields: Wind tunnel testing. Preprints, Ninth Symp. on Meteorological Observations and Instrumentation, Charlotte, NC, Amer. Meteor. Soc., 179–183.

    • Search Google Scholar
    • Export Citation
  • Canfield, N. L., , and McNitt J. A. , 1991: Automated Surface Observing System data for climatic analysis, research and service. Preprints, Seventh Symp. on Meteorological Observations and Instrumentation, New Orleans, LA, Amer. Meteor. Soc., 213–216.

    • Search Google Scholar
    • Export Citation
  • Croft, P. J., , and Robinson D. A. , 1993: The impact of MMTS on the New Brunswick climate record. Preprints, Eighth Symp. on Meteorological Observations and Instrumentation, Anaheim, CA Amer. Meteor. Soc., J12–J15.

    • Search Google Scholar
    • Export Citation
  • Dewitt, D. P., , and Nutter G. D. , 1989: Theory and Practice of Radiation Thermometry. Wiley Interscience, 1138 pp.

  • Doesken, N. J., , McKee T. B. , , and Harrington J. W. , 1995: MMTS—Ten years after. Preprints, Ninth Symp. Conf. on Applied Climatology, Dallas, TX, Amer. Meteor. Soc., 21–24.

    • Search Google Scholar
    • Export Citation
  • Easterling, D. R., , Quayle R. G. , , and Hughes P. Y. , 1993: The effects of thermometer changes on the temperature record of U.S. first-order stations. Preprints, Eighth Symp. on Meteorological Observations and Instrumentation, Anaheim, CA, Amer. Meteor. Soc., J3–J5.

    • Search Google Scholar
    • Export Citation
  • Fuchs, M., , and Tanner C. B. , 1965: Radiation shields for air temperature thermometers. J. Appl. Meteor, 4 , 544547.

  • Gall, R., , Young K. , , Schotland R. , , and Schmit J. , 1992: The recent maximum temperature anomalies in Tucson: Are they real or an instrument problem? J. Climate, 5 , 657665.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Gill, G. C., 1979: Development of a small radiation shield for air temperature measurements on drifting buoys. NOAA Buoy Office Rep., Contract 01-7-038-827, 23 pp.

    • Search Google Scholar
    • Export Citation
  • Gill, G. C., 1983: Comparison testing of selected naturally ventilated solar radiation shields. NOAA Buoy Office Rep., Contract NA-82-0A-A-266, 15 pp.

    • Search Google Scholar
    • Export Citation
  • Guttman, N. B., , and Baker C. B. , 1996: Exploratory analysis of the difference between temperature observations recorded by ASOS and conventional methods. Bull. Amer. Meteor. Soc, 77 , 28652873.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Holman, J. P., 1997: Heat Transfer. 8th ed., McGraw-Hill, 696 pp.

  • Karl, T. R., , Tarpley J. D. , , Quayle R. G. , , Diaz H. F. , , Robinson D. A. , , and Bradley R. S. , 1989: The recent climate record: What it can and cannot tell us. Rev. Geophys, 27 , 405430.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Kessler, R. W., , Bosart L. F. , , and Kleist J. , 1993: Recent maximum temperature anomalies at Albany, New York: Fact or fiction? Bull. Amer. Meteor. Soc, 74 , 215226.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Lin, X., 1999: Microclimate inside air temperature radiation shields. Ph.D. thesis, University of Nebraska, Lincoln, 187 pp.

  • Lin, X., , Hubbard K. G. , , and Meyer G. E. , 2001: Airflow characteristics of commonly used temperature radiation shields. J. Atmos. Oceanic Technol, 18 , 329339.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Luers, J. K., 1989: The influence of environmental factors on the temperature of the radiosonde thermistor. Ph.D. thesis, University of Tennessee, 169 pp.

    • Search Google Scholar
    • Export Citation
  • Luers, J. K., 1992: Absolute accuracy of the multi-thermistor radiosonde for measuring atmospheric temperature. NASA Goddard Space Flight Center Rep., Contract NAS5-31661, 54 pp.

    • Search Google Scholar
    • Export Citation
  • Luers, J. K., , and Eskridge R. E. , 1995: Temperature corrections for the VIZ and Vaisala radiosondes,. J. Appl. Meteor, 34 , 12411253.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • MacHattie, L. B., 1965: Radiation screens for air temperature measurements. Ecology, 46 , 533538.

  • McKay, D. J., , and McTaggart-Cowan J. D. , 1977: An intercomparison of radiation shields for auto stations. WMO Tech. Conf. on Instruments and Methods of Observation, Geneva, Switzerland, WMO No. 480, 208–213.

    • Search Google Scholar
    • Export Citation
  • McKee, T. B., , Doesken N. J. , , and Kleist J. , 1993: A preview of temperature and precipitation data continuity into the ASOS (Automated Surface Observing System) era. Preprints, Eighth Symp. on Meteorological Observations and Instrumentation, Anaheim, CA, Amer. Meteor. Soc., J16–J21.

    • Search Google Scholar
    • Export Citation
  • McTaggart-Cowan, J. D., , and McKay D. J. , 1976: Radiation shields—An intercomparison. Atmospheric Environment Service of Canada Misc. Rep., 9 pp.

    • Search Google Scholar
    • Export Citation
  • Meyer, S. J., , and Hubbard K. G. , 1992: Nonfederal automated weather stations and networks in the United States and Canada: A preliminary survey. Bull. Amer. Meteor. Soc, 73 , 449457.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • National Weather Service, 1983: Maximum/minimum temperature system operation instructions. NWS Misc. Rep., 5 pp.

  • OMEGA Engineering, Inc., 1995: The Temperature Handbook. Vol. 29. OMEGA Engineering, Inc., Stamford, CT, 1494 pp.

  • Quayle, R. G., , Easterling D. R. , , Karl T. R. , , and Hughes P. Y. , 1991:: Effects of recent thermometer changes in the cooperative station network. Bull. Amer. Meteor. Soc, 72 , 17181723.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Richardson, S. J., , and Brock F. V. , 1995: Passive solar radiation shields: Energy budget—Optimizing shield design. Preprints, Ninth Symp. on Meteorological Observations and Instrumentation, Charlotte, NC, Amer. Meteor. Soc., 259–264.

    • Search Google Scholar
    • Export Citation
  • Robinson, D. A., 1990: The United States cooperative climate-observing system: Reflections and recommendations. Bull. Amer. Meteor. Soc, 71 , 215226.

    • Search Google Scholar
    • Export Citation
  • Schmidlin, F. J., , Sang Lee H. , , and Ranganayakamma B. , 1995: Deriving the accuracy of different radiosonde types using the three-thermistor radiosonde technique. Preprints, Ninth Symp. on Meteorological Observations Instrumentation, Charlotte, NC, Amer. Meteor. Soc., 27–31.

    • Search Google Scholar
    • Export Citation
  • Sterling Research & Development Center, 1973: Test and evaluation of the Israeli instrument shelter. Lab. Interim Rep. 8/73, National Weather Service Functional Experimentation and Testing Branch, 14 pp.

    • Search Google Scholar
    • Export Citation
  • Tanner, B. D., , Swiatek E. , , and Maughan C. , 1996: Field comparisons of naturally ventilated and aspirated radiation shields for weather station air temperature measurements. Preprints, 22d Conf. on Agricultural and Forest Meteorology, Atlanta, GA, Amer. Meteor. Soc., 227–230.

    • Search Google Scholar
    • Export Citation
  • Tarnopolsky, M., , and Seginer I. , 1999: Leaf temperature error from heat conduction along thermocouple wires. Agric. For. Meteor, 9 , 185194.

    • Search Google Scholar
    • Export Citation
  • Valvano, J. W., 1992: Temperature measurements. Advances in Heat Transfer. Bioengineering Heat Transfer, Y. I. Cho, Ed., Book News, 359–436.

    • Search Google Scholar
    • Export Citation
  • Wendland, W. M., , and Armstrong W. , 1993: Comparison of maximum-minimum resistance and liquid-in-glass thermometer records. J. Atmos. Oceanic Technol, 10 , 233237.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Whitaker, S., 1972: Forced convection heat-transfer corrections for flow in pipes, past flat plates, single cylinders, single sphere, and flow in packed bids and tube baundles. AIChE J, 18 , 361371.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Wylie, R. G., , and Lalas T. , 1992: Measurement of temperature and humidity: Specification, construction, properties and use of the WMO reference psychrometer. WMO Rep. 759, 71 pp.

    • Search Google Scholar
    • Export Citation
All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 71 71 8
PDF Downloads 37 37 6

Some Perspectives on Recent In Situ Air Temperature Observations: Modeling the Microclimate inside the Radiation Shields

View More View Less
  • 1 School of Natural Resource Sciences, University of Nebraska, Lincoln, Lincoln, Nebraska
  • | 2 Biological Systems Engineering Department, University of Nebraska, Lincoln, Lincoln, Nebraska
© Get Permissions
Restricted access

Abstract

Air temperature measurement has inherent biases associated with the particular radiation shield and sensor deployed. The replacement of the Cotton Region Shelter (CRS) with the Maximum–Minimum Temperature System (MMTS) and the introduction of Automated Surface Observing System (ASOS) air temperature observing systems during the NWS modernization introduced bias shifts in federal networks that required quantification. In rapidly developing nonfederal networks, the Gill shield temperature systems are widely used. All of these systems house an air temperature sensor in a radiation shield to prevent radiation loading on the sensors; a side effect is that the air temperature entering a shield is modified by interior solar radiation, infrared radiation, airspeed, and heat conduction to or from the sensor so that the shield forms its own interior microclimate. The objectives of this study are to develop an energy balance model to evaluate the microclimate inside the ASOS, MMTS, Gill, and CRS shields, including the interior solar radiation, infrared radiation, and airspeed effects on air (sensor) temperature under day and night conditions. For all radiation shields, the model air temperature for shield effects was in good agreement between shields while the uncorrected “normal operating” temperatures were more variable from shield to shield. The solar radiation loading ratio was dramatically increased with a corresponding increase in the solar elevation angle for all shields except the ASOS shield, and are ranked as Gill > MMTS ≈ CRS > ASOS. The daytime infrared radiation effects on air temperature were ranked as ASOS > Gill > MMTS > CRS, but the nighttime infrared radiation effects were not so large and were uniformly distributed among negative and positive effects on air temperatures. For the nonaspirated radiation shields (MMTS, Gill, and CRS), increasing ambient wind speed improved the accuracy of air temperatures, but it was impossible to reach the accuracy claimed by manufacturers when the in situ measurements were taken under lower ambient wind speed (<4 ∼ 5 m s−1).

 *Nebraska Agricultural Experiment Station Journal Number 13008.

Corresponding author address: Dr. Kenneth G. Hubbard, 242 L. W. Chase Hall, University of Nebraska, Lincoln, Lincoln, NE 68583-0728. Email: khubbard1@unl.edu

Abstract

Air temperature measurement has inherent biases associated with the particular radiation shield and sensor deployed. The replacement of the Cotton Region Shelter (CRS) with the Maximum–Minimum Temperature System (MMTS) and the introduction of Automated Surface Observing System (ASOS) air temperature observing systems during the NWS modernization introduced bias shifts in federal networks that required quantification. In rapidly developing nonfederal networks, the Gill shield temperature systems are widely used. All of these systems house an air temperature sensor in a radiation shield to prevent radiation loading on the sensors; a side effect is that the air temperature entering a shield is modified by interior solar radiation, infrared radiation, airspeed, and heat conduction to or from the sensor so that the shield forms its own interior microclimate. The objectives of this study are to develop an energy balance model to evaluate the microclimate inside the ASOS, MMTS, Gill, and CRS shields, including the interior solar radiation, infrared radiation, and airspeed effects on air (sensor) temperature under day and night conditions. For all radiation shields, the model air temperature for shield effects was in good agreement between shields while the uncorrected “normal operating” temperatures were more variable from shield to shield. The solar radiation loading ratio was dramatically increased with a corresponding increase in the solar elevation angle for all shields except the ASOS shield, and are ranked as Gill > MMTS ≈ CRS > ASOS. The daytime infrared radiation effects on air temperature were ranked as ASOS > Gill > MMTS > CRS, but the nighttime infrared radiation effects were not so large and were uniformly distributed among negative and positive effects on air temperatures. For the nonaspirated radiation shields (MMTS, Gill, and CRS), increasing ambient wind speed improved the accuracy of air temperatures, but it was impossible to reach the accuracy claimed by manufacturers when the in situ measurements were taken under lower ambient wind speed (<4 ∼ 5 m s−1).

 *Nebraska Agricultural Experiment Station Journal Number 13008.

Corresponding author address: Dr. Kenneth G. Hubbard, 242 L. W. Chase Hall, University of Nebraska, Lincoln, Lincoln, NE 68583-0728. Email: khubbard1@unl.edu

Save