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Fig. 1.2 : Standard non-recording Rain-gauge of Indian Meteorological
Department
(After S.K. Garg, 1988)
Standard rain gauges :
Standard rain gauge consists of a collector, with a gun
metal rim, a base and a polythene bottle (Fig. 1.2). Both the collector and the
base are made up of fibre glass reinforced polythene. The collector with a deep
set funnel having an aperture of either 100 or 200 sq.cm. are interchangeable
depending upon the area and expected rainfall. There are also two bases, the
smaller and the other larger and are also inter changeable, the smaller one
being used for all sizes of rain gauges except the largest. The polythene bottles
have three capacities i.e. 2 litres, 4 litres and 10 litres. By interchanging the
collector, base and the polythene bottles depending upon the rainfall pattern,
rain gauges as set up in our country can measure the rainfall more or less
accurately, subjected to corrections due to wind speed, direction of rainfall etc.
Data from these gauges are collected manually by a person who visits the site
at 8.30 am daily for recording 24 hours rainfall.
