How do you calculate effective rainfall?
Effective Precipitation (mm) = (RAIN – 5) x 0.75 During extended periods of cool wet weather, less evaporation takes place and the smaller rainfall events may be effective precipitation.
How is effective rainfall calculated in a hyetograph?
The effective rainfall hyetograph, for which the runoff is to be calculated using the unit hydrograph, is obtained by deducting initial and Version 2 CE IIT, Kharagpur Page 10 infiltration losses from the recorded rainfall. This effective rainfall hyetograph is divided into blocks of T-hour duration.
Why is effective rainfall calculated?
Effective precipitation is important in irrigation scheduling decisions, is used to design new irrigation systems, and is a guiding factor for planning crop production practices. Estimating the portion of a rainfall that leaves a field as runoff is difficult.
What is effective rainfall in agriculture?
In simplest terms, effective rainfall means useful or utilizable rainfall for crop production. The rainfall which is utilised by crops especially for evapotranspiration can be called as effective rainfall.
How does land topography influence effective rainfall?
These properties influence infiltration and through this the effective rainfall quantum. The amount of effective rainfall is greater when the water table is deep than when it is shallow….6. Factors influencing effective rainfall.
| Factor | Relevant characteristics |
|---|---|
| Land | Topography, slope, type of use; |
What is effective rainfall depth?
The term effective rainfall usually refers to runoff. If I measured 1 inch rainfall, and 0.2 inches was measured from the storm as streamflow, the effective rainfall would be 0.2 Inches. If there is no runoff, the effective rainfall is 0. Cite.
Which one of the followings is not true for effective rainfall?
1. Which of the following statement is not correct about Effective rainfall? Explanation: Effective rainfall is that portion of precipitation that remains in the soil and is available for consumptive use.
How do you calculate runoff from rainfall?
Simple, straightforward methods of calculating runoff can tell you the amount of water that storms bring to the earth. For a given surface area such as a roof or yard, multiply the area by the inches of rainfall and divide by 231 to obtain the runoff in gallons.
What is a rainfall hyetograph?
A hyetograph is a graphical representation of the distribution of rainfall intensity over time. The maximum intensity may not be reached as uniformly as shown in the SCS hyetographs.
What are the 4 rainfall characteristics?
The characteristics of rainfall are the amount, the intensity, the duration, the frequency or return period, and the seasonal distribution.
What are the five factors that influence rainfall?
Factors controlling the distribution of rainfall over the earth’s surface are the belts of converging-ascending air flow (see doldrums; polar front), air temperature, moisture-bearing winds, ocean currents, distance inland from the coast, and mountain ranges.
Effective rainfall. Définition. Effective rainfall (or precipitation) is equal to the difference between total rainfall and actual evapotranspiration. Effective rainfall can be calculated directly from the climatic parameters and the useable ground reserves (RU).
What is effective rainfall in hydrograph?
Effective rainfall – sometimes called excess rainfall – is the component of the storm hyetograph which is neither retained on the land surface nor which infiltrates into the soil. The effective rainfall produces overland flow that results in the direct runoff hydrograph…
What is the definition of effective rainfall?
Definition. Effective rainfall (or precipitation) is equal to the difference between total rainfall and actual evapotranspiration. Effective rainfall can be calculated directly from the climatic parameters and the useable ground reserves (RU). At ground level, water from effective rainfall is split into two fractions: surface run-off…
What is the difference between Storm and effective rainfall hyetographs?
The effective rainfall produces overland flow that results in the direct runoff hydrograph from a sub-area of a catchment. The difference between the storm and the effective rainfall hyetographs is termed the abstractions or rainfall losses. Abstractions are made up of one or more of the following three main components:-