Lecture 7 Precipitation (4)

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Lecture 7Precipitation (4)
Precipitation Data Analysis

• Purpose
• Mean and Standard Deviation
• Characteristics of Individual Storms
• Envelope Curves
• Reoccurrence Intervals

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Precipitation Statistical Analysis
The analysis serves for multiple purposes
Ø    Agriculture Ø      Ecology Ø     
Geomorphology Ø      Agro-engineering Ø     
Civil engineering
Ø     
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Simple Precipitation Statistics
1. Mean
2. Standard Deviation
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Characteristics of Individual Storms (1)
The maximum rainfall averaged for an area in a
given period generally decreases with the size of
the area
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Characteristics of Individual Storms (2)
The return period for a rainfall intensity is
longer for an area than for a point
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Probable maximum precipitation
i)    PMPMean precipitation coefficient ?
Standard deviation ii)                  
PMPObs. Max. Precip? Max. Pos. Water Content in
Clouds
Water content in clouds of concern
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Intensity-duration-frequency relationships
Rainfall (mm)