Specifications

18
TEAM Climate Monitoring Protocol 3.1
4.3.2 Siting the Radiation Sensor
In many cases, although the clearing for the climate station is not appropriate to site the solar radiation
sensor, there might be a structure within the immediate vicinity of the climate station (roof top, pole,
water tower) where the radiation sensor can be installed, fulfilling its siting requirements (no obstacles
above 5 degrees from the horizon, Table 2). If this is the case, the radiation sensors can be mounted
at this location and connected to the data logger with a cable up to a 100 m long. Since the sensor
produces voltage signals that are very small (mV), the resistance encountered by the signal in longer
cables might compromise its integrity, so this needs to be taken into account when ordering the sensor.
Use the following guidelines when siting the radiation sensor:
 Consult with the TEAM Technical Liaison or Technical Director on an appropriate site for
the sensor if there is one within 50-60 from the proposed location of the climate station.
Do this before ordering the equipment since the specs for the sensor are slightly different
(longer cable length).
 Make sure the location for the radiation sensor meets the required siting guidelines (Table
2). Mount it properly making sure it is leveled (see Section 5.6.2).
 If the radiation sensor is mounted on a pole, make sure the structure is solid and stable in
the wind. If the structure sways too much in the wind, the reading will be invalid.
 The radiation sensor might be mounted on a rooftop, but h
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, since the sensor will pick up radiation
reflected from the structure (WMO 2008).
Another possibility is to mount the climate sensor on the tower as high as possible. Perhaps a 6-10 m
tall mounting pole can be attached to the side of the tower and the sensors mounted on the top of this
pole rather than on the tower itself.
4.4 Level 3 Siting
In many sites it might be difficult to find a clearing that complies with the requirements for Level 1
(siting requirements for all three sensors are met) or Level 2 (siting requirements for precipitation and
temperature are met). In such cases, it is suggested that the station is located in a clearing that is the
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to a Level 2 clearing (see Section 4.3) and that the site conditions are
carefully documented and monitored annually (see Section 5.7.2). In particular, watch for the
following:
 Make sure the Temperature/RH sensor is as far as possible from surrounding vegetation to
minimize microclimatic conditions that could affect the readings.
 Ensure that the precipitation gauge has a clear view of the sky and is as far as possible from
surrounding obstacles to avoid water ‘bouncing in’ from other sources, thus influencing the
readings.
 Locate the radiation sensor following the guidelines for Level 2 (within 50-60 m of the climate
station). If this is not feasible, install the radiation sensors as high as possible in the current
climate base and document carefully the site conditions (see Section 5.7.2).
 Always document carefully the site conditions following the guidelines in Section 5.7.2 and
monitor site conditions annually.