Effective rainfall: Defined as that part of the rainfall ...damanhour.edu.eg/pdf/agrfac/حاسب...
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Average monthly rainfall: Mathematically determined average for a series of rainfall records to be used for CWR calculation Dependable rainfall: The dependable rainfall (having probability of 80%) is used for the design of the irrigation system capacity. Rainfall in wet, normal and dry years: Effective rainfall: Defined as that part of the rainfall which is effectively used by the crop after rainfall losses due to surface run off and deep percolation Rainfall in wet, normal and dry years wet normal dry 80 % probability 50 % probability 20 % probability
Transcript of Effective rainfall: Defined as that part of the rainfall ...damanhour.edu.eg/pdf/agrfac/حاسب...
Average monthly rainfall: Mathematically determined average
for a series of rainfall records to be used for CWR calculation
Dependable rainfall: The dependable rainfall (having
probability of 80%) is used for the design of the irrigation
system capacity.
Rainfall in wet, normal and dry years:
Effective rainfall: Defined as that part of the rainfall which is
effectively used by the crop after rainfall losses due to surface
run off and deep percolation
Rainfall in wet, normal and dry years
wet normal dry
80 %
probability
50 %
probability
20 %
probability
For programming of irrigation water supply and management,
rainfall data of normal, wet and dry years are used.
i.Tabulate yearly rainfall totals for a given period.
ii. Arrange data in descending order of magnitude.
iii. Tabulate plotting position according to:
Fa = 100 * m / (N + 1) where: N = number of records
m = rank number , and Fa = plotting position
Rainfall Data Processing
iv.Plot values on log-normal scale and obtain the logarithmic regression
equation, as shown in the following figure
(2) Input Rain Data
(2)Press New
Exportation CilmWat Data To CropWat
Double Click (in Desktop ) CLIMWAT 2.0 for
CROPWAT
You have two Options (1) Coordinates (2) Country
❑Select Egypt❑Click “ Display all stations within selected country
You have two Options (1) Coordinates (2) Country
The window composes from two parts:(1) metrological stations (white points)(2) their coordinates
❑Select Egypt❑Click “ Display all stations within selected country
Location of all available Metrological Stations Display as White Circle
Selection meteorological stations
Color of Location of Selected Metrological Stations Changes from white to red
c:\Program Files\CLIMWAT 2.0 for CROPWAT V2.0
C:\ My_CLIMWAT_Files
1. Select « My_CLIMAT_Files »
2. Double Click « My_CLIMAT_Files »
3. Click « Export .PEN and .CLI files ».
Create the folder “ My_CLIMWAT_Files at Drive C
Export Selected Stations to folder
Export Selected Stations to CropWat
OK
Exit
Display Egypt Coordinates
More … More
Options to display Metrological Stations
As Station number
As Names
As Altitude
Latitude and Longitude
