Symons Rain Gauge - Diagram | Advantages | Disadvantage

 Symons Rain Gauge

Precipitation (of all kinds) is measured in terms of depth of water (in millimeters) that would accumulate on a level surface if the precipitation remained where it fell. A variety of instruments have been developed for measuring precipitation (or precipitation rate) and are known as precipitation gauges or, simply, rain gauges which are classified as either recording or non recording rain gauges.

Non-recording rain gauges only collect rain water which, when measured suitably, gives the total amount of rainfall at the rain gauge station during the measuring interval. The Indian Meteorological Department has adopted Symon’s rain gauge (Fig. 1.). A glass bottle and funnel with brass rim are put in a metallic cylinder such that the top of the cylinder is 305 mm above the ground level. Rain water falls into the glass bottle through the funnel. The

water collected in the bottle is measured with the help of a standard measuring glass jar which is supplied with the rain gauge. The jar measures rainfall in millimeters. At each station, rainfall observations are taken twice daily at 8.30 a.m. and 5.30 p.m.

Fig 1. Symon’s rain gauge

Advantage of Symon's Rain Gauge

1.     It helps to measure all forms of precipitation or rainfall which comprised snow and rain.

2.     Removing its funnel collector permits the accumulation of solid rainfall and also plays a significant role in estimating cold climates.

3.     Rainwater collected is measured on daily basis.

 Disadvantage of Symon's rain gauge 

1.     This type of gauge only collects rain.

2.     This gauge does not record and measure the rainfall simultaneously.

3.     Symons rain gauge only shows how much rain has fallen.

4.     One of the main disadvantages of Symons rain gauge is that we cannot determine when the rain began, the intensity with which the rain was falling, when the rain stopped and variation in the intensity of rain throughout the rainy period.