Specifications

TEAM Climate Monitoring Protocol 3.1
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3.3.1 Temperature/Relative Humidity Sensor – Vaisala HMP45C
The TEAM Climate Protocol uses two Vaisala HMP45C sensors, which measures both relative humidity
(%) and air temperature (ºC). These sensors are housed in an aspirated radiation shield to avoid the
influence of solar radiation on the measurements. The shield type used for this sensor is the
MetOne
076B-5
, which stabilizes readings by allowing air to move past the sensor. Two temperature/RH
sensors are housed in the aspirated radiation shield.
3.3.2 Precipitation Gauge – Hydrological Services TB4
The use of an automatic but sensitive precipitation gauge with low error in recording intense rainfall
events (very common in tropical areas) is essential. The
Hydrological Services TB4 rain gauge funnels
rain into a tipping bucket mechanism that tips when 0.25 mm of rain has been collected. Each tip is
marked by a dual reed switch closure that is recorded by the data logger. After measurement, the
water drains through two orifices in the base, allowing the measured water to be collected in a
separate container if desired.
The rain gauge includes a siphoning mechanism that allows the rain to flow at a steady rate to the
tipping bucket mechanism regardless of rainfall intensity which reduces typical rain bucket errors,
enabling the gauge to record intense rainfall events. As a backup, we recommend installing a regular,
manual precipitation gauge to double check heavy precipitation measurements (>50 mm/hour). Both
precipitation gauges should be mounted at least 6 m from the main climate station tower and at least
30 cm above the ground (see Section 5.6.3).
There is also a windscreen manufactured by Novalynx that will need to be installed around the
precipitation gauge to prevent inaccuracies in measurements caused by strong winds (see Section
5.6.3).
3.3.3 Solar Radiation – Licor LI200X
This is a silicon-photovoltaic pyranometer that measures global solar radiation (both direct and diffuse
radiation). Although less sensitive than the most sophisticated thermopile pyranometers, the
Licor
LI200X
has medium stability (± 2% per year) and acceptable accuracy (3%-5%) for baseline
measurements. The
LI200X should be mounted in an area with near complete view of the sky (no
obstacles 5 degrees above the horizon), which in many cases might require it to be installed in a
separate location from the rest of the sensors (see Section 4 for siting information). Sensors are
mounted in duplicate (one facing north and one facing south) to account for seasonal movements in
the solar path and to serve as a backup (see Section 5.6.2 for more installation details).
3.4 Power supply
3.4.1 Solar Panel – Yingli YL-85
A solar panel provides the energy needed to keep the station running and charging the battery for
night operation. The solar panel will still provide some power on cloudy days, but not as much as on
sunny days. Still, one should not be concerned about losing data due to power failure unless there is
an exceptionally long period of cloudiness. The recommended solar panel is the
Yingli YL-85 because
of its ability to produce 85 Watts of power (enough to run the station during the day) and because it
can be mounted either on the side of the
UT10 tower (see Section 5.5 for installation instructions) or, if
there is not enough light, on a pole near the station.