net.simplace.sim.components.evapotran.fao56.ReferenceETPMHourly

Calculates reference evapotranspiration ET0 by Penman-Monteith with the FAO56 approach.

FAO Penman-Monteith equation determines the evapotranspiration from the hypothetical grass reference surface. (FAO 56)

Uses daily max/min temperature, actual vapour pressure, net radiation and wind speed. Checks for valid actual vapour pressure values.

For documentation of the formulas please check the orginal reference (FAO 56)

References

[http://www.fao.org/docrep/x0490e/x0490e00.htm (FAO 56): Allen, Crop evapotranspiration - Guidelines for computing crop water requirements - FAO Irrigation and drainage paper 56, 1998]

Component Variables

Content Type	Name	Description	Data Type	Unit	Min Value	Max Value	Default Value
constant	cAltitude	elevation above sea level	DOUBLE	m	-	-	0.0
constant	cLatitude	latitude	DOUBLE	°	-90.0	90.0	0.0
input	iActualVapourPressure	actual vapour pressure	DOUBLEARRAY	kPa	-	-	null null null null null null null null null null null null null null null null null null null null null null null null
input	iNetRadiation	net radiation	DOUBLEARRAY	megajoule_per_square_metre_hour	-	-	null null null null null null null null null null null null null null null null null null null null null null null null
input	iT	hourly daily temperature	DOUBLEARRAY	°C	-	-	null null null null null null null null null null null null null null null null null null null null null null null null
input	iWindspeed	wind speed at 2m height	DOUBLEARRAY	m/s	-	-	null null null null null null null null null null null null null null null null null null null null null null null null
out	ReferenceCropEvapotranspiration	hourly reference evapotranspiration (ET0)	DOUBLEARRAY	mm/h	-	-	null null null null null null null null null null null null null null null null null null null null null null null null
out	ReferenceCropEvapotranspirationDaily	daily reference evapotranspiration (ET0)	DOUBLE	mm/d	-	-	0.0

public class ReferenceETPMHourly extends net.simplace.sim.model.FWSimComponent {
// Public Constructors
public ReferenceETPMHourly();

// Public Instance Methods

public HashMap createVariables(); // Defines
net.simplace.sim.model.FWSimComponent

Create the FWSimVariables as interface for this SimComponent

// Protected Instance Methods

protected void init(); // Defines net.simplace.sim.model.FWSimComponent

Initializes the fields by getting input and output FWSimVariables from VarMap

protected void process(); // Defines net.simplace.sim.model.FWSimComponent

Process the algorithm and write the results back to VarMap

protected FWSimComponent clone(FWSimVarMap aVarMap);
// Defines net.simplace.sim.model.FWSimComponent

creates a clone from this SimComponent for use in other threads

}

Hierarchy: java.lang.Object - net.simplace.sim.model.FWSimComponent (net.simplace.sim.util.FWSimFieldContainer) - ReferenceETPMHourly