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| | Temperature | | Temperature | ||
| + | | Maximum and minimum temperature | ||
| + | | Some ET<sub>0</sub> calculation methods use average temperature only. AgrometShell needs both minimum and maximum temperatures. | ||
| + | |- | ||
| + | |- | ||
| + | | Radiation (MJ/m<super>2</super> | ||
| | Maximum and minimum temperature | | Maximum and minimum temperature | ||
| | Some ET<sub>0</sub> calculation methods use average temperature only. AgrometShell needs both minimum and maximum temperatures. | | Some ET<sub>0</sub> calculation methods use average temperature only. AgrometShell needs both minimum and maximum temperatures. | ||
Revision as of 08:25, 4 August 2006
Chapter 11. Development of ET0 computation procedure.
Potential evapotranspiration (ET0) is a vital input to Water Balance calculations, which in turn are a vital part in Crop forecasting. The parameters needed to calculate ET0 are the following:
Parameter group Parameters Remarks Temperature Maximum and minimum temperature Some ET0 calculation methods use average temperature only. AgrometShell needs both minimum and maximum temperatures. Radiation (MJ/m<super>2</super> Maximum and minimum temperature Some ET0 calculation methods use average temperature only. AgrometShell needs both minimum and maximum temperatures.
- Temperatures : minimum and maximum in degrees celcius
- Radiation. Radiation can be calculated quite accurately from the number of sunshine hours (or sunshine fraction) accompanied by Day number in the year