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In this lesson we are going to learn how to measure rainfall, the instrument used in measuring rainfall and also calculations of differents aspects of rainfall

Answer Text:
Rainfall

Rain gauge is the instrument used to measure the amount of rainfall in a day.
It should be made of impermeable material which can’t absorb water. How It’s Used/Works
• It’s taken to an open space to prevent water from dropping into the funnel.
• Its sunk into the ground to prevent evaporation
• The funnel top is left 30cm above the ground to prevent splashes of water and run off.
• After 24 hours water is emptied into the measuring cylinder.
• The reading of the amount of rainfall is got from the measuring cylinder in millimetres.
• The figure represents the millimetres of water falling on each square millimetre of the ground.
• It could be used to measure snow fall by melting it before the readings are gotten.
Calculating Rainfall
1. Monthly Rainfall Total
-Sum of rainfall recorded in a month.
2. Annual Rainfall Total
- Sum of monthly rainfall totals for 12 months.
3. Mean Monthly Rainfall
-Sum of rainfall totals for a particular month over several years divided by the number of the years of observation.
4. Mean Annual Rainfall
-Sum of mean monthly rainfall for 12 months of the year.