Campbell Scientific UT20 and UT30 Tower-based Weather Stations - Manual (Page 16)

UT20 and UT30 Tower-based Weather Stations
4.4 Solar Radiation
Pyranometers should be located to avoid shadows on the sensor at any time.
Mounting it on the southernmost (northern hemisphere) portion of the weather
station will minimize the chance of shading from other weather station
structures. Reflective surfaces and sources of artificial radiation should be
avoided. The height at which the sensor is mounted is not critical.
4.5 Soil Temperature
The measurement site for soil temperature should be at least 1 m 2 and typical
of the surface of interest. The ground surface should be level with respect to
the immediate area (10 m radius).
Standard measurement depths:
10.0 cm ± 1.0 cm (AASC)
5.0 cm, 10.0 cm, 50.0 cm, 100.0 cm (WMO)
FIGURE 4-1. Effect of structure on wind flow
4.6 Siting References
1 EPA, (1987). On-Site Meteorological Program Guidance for Regulatory
Modeling Applications, EPA-450/4-87-013. Office of Air Quality Planning
and Standards, Research Triangle Park, North Carolina 27711.
2 WMO, (1983). Guide to Meteorological Instruments and Methods of
Observation. World Meteorological Organization No. 8, 5th edition, Geneva,
Switzerland.
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