MEASURINNG MEATEOROLOGICAL DATA
B.W.N.C DHANAPALA
UWU/EAG/20/062
AGRICULTURAL METEOROLOGY AND CLIMATOLOGY
EXPORT AGRICULTURE DEGREE PROGRAMME EAG141-2
1ST YEAR- 1ST SEMESTER
, 01) ESTABLISHMENT CRITERIA OF A METEOROLOGICAL STATION
1. The site should contain a flat rectangular plot with 55 meters in north-south direction and
36 meters in east-west direction,
2. The site must be representative of climate, soils and agricultural (cropping) conditions of
the area and should be located at the center of the farm,
3. The site must be free from water logging and easily accessible throughout the year,
4.Site selected should be away from hills, buildings, streams and trees to avoid shade, shield
or channel affects,
5.It should be away from steep slopes, water bodies and frequent irrigation.
6.The recommendable distance from the obstacles from the rain gauge and other instruments
are at least twice and 10 times the height of the obstructions, respectively.
Below are some sensor location guidelines from weather
station manufacturer Campbell Scientific:
Wind speed and direction: Wind sensors should be
located over open, level terrain as far away from
any nearby obstructions (e.g., buildings, trees, etc.)
as possible-ideally a distance equal to 10 times the height of the closest obstruction;
Temperature and relative humidity sensors should be located over an open, level area
at least 10 m (about 30 ft.) in diameter. The surface should be covered with short grass
or another natural surface. These sensors should be located a distance of at least four
times the height of any nearby obstruction, or at least 30 m (about 100 ft.) from large
paved areas.
Sensors should be encased within a well-ventilated shield for protection from thermal
radiation. Rooftops, steep slopes, high vegetation, shaded areas, swamps, low places
that hold standing water after rains, and large industrial heat sources should be avoided
Solar radiation: Sensors should be mounted on the southernmost (in the Northern
Hemisphere) side of the station to prevent exposure to shadows. Reflective surfaces and
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