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net.simplace.sim.transformers.DiurnalSineWeatherTransformer

Transforms daily radiation and temperature to diurnal values using sine curves.

Temperature follows a sine curve during daylight and an exponential decay curve during night between minimum and maximum temperature.

Radiation follows one of the curves specified by the user

Sine - a simple sine curve ,
SinBeta - sine of solar elevation (shifted sine curve)
SinBetaEffective - as SinBeta, but corrected for lower atmospheric transmission at lower solar elevation.

as defined by (G).

Input variables

The field names (column names) of date, radiation, min and max temperature in the resource (CHAR)
The number of steps the diurnal values are calculated (default is 24, i.e. hourly values) (INT)
Latitude of the location (DOUBLE)
The offset from noon of max temp (default 1.5, i.e. max temperature occurs at 1:30 pm) (DOUBLE)
The nocturnal time coefficient for temperature (default is 4 hours) (DOUBLE)
The radiation curve that should be used - one of Sine, SinBeta or SinBetaEffective (CHAR)

Output variables

Output variables in the following order

Key column(s) of the original resource (including date) in the same order and same datatype
Time - Array of time for each step (h) (INTARRAY)
Temperature - Array of Temperature for each step (°C) (DOUBLEARRAY)
Radiation intensity - Array of radiation intensity for each time step (J m^-2 h^-1, kJ m^-2 h^-1 or MJ m^-2 h^-1) (DOUBLEARRAY)
Radiation - Array of radiation accumulated between two time steps (DOUBLEARRAY)
DOY - day of year (d) (INT)
Daylength - (h) (DOUBLE)
Daily total radiation - (J m^-2, kJ m^-2 or MJ m^-2) (DOUBLE)

Example

First we need a resource with daily weather, including min and max temp and radiation.

|    <resource id="weather" interface="weatherfile" frequence="DAILY">
|      <header>
|        <res id="KeyValue" datatype="CHAR" key="vWeatherKey"/>
|        <res id="PolygonCode" datatype="CHAR" />
|        <res id="CURRENTDATE" datatype="DATE" key="CURRENT.DATE" />
|        <res id="Rain" unit="mm" datatype="DOUBLE" />
|        <res id="AirTemperatureMax" unit="°C" datatype="DOUBLE" />
|        <res id="AirTemperatureMin" unit="°C" datatype="DOUBLE" />
|        <res id="GlobalSolarRadiation" unit="MJ*m**-2" datatype="DOUBLE" />
|        <res id="WindSpeed" unit="m*s**-1" datatype="DOUBLE" />
|        <res id="ReferenceEvapotranspiration" unit="mm" datatype="DOUBLE" />
|      </header>
|    </resource>

The transformer needs the resource id in it's resource attribute. Output variables in the header section start with the resources key variables, followed by calculated variables. The inputs for DateField, !MinTempField, MaxTempField and RadiationField contain the names of the columns as defined in the resource above.

|    <transform id="diurnal" frequence="DAILY" resource="weather" class="net.simplace.sim.transformers.DiurnalSineWeatherTransformer">
|      <header>
|        <res id="KeyValue" datatype="CHAR" key="vWeatherKey"/>
|        <res id="CURRENTDATE" datatype="DATE" key="CURRENT.DATE" />
|        <res id="Hours" datatype="DOUBLEARRAY" />
|        <res id="Temperature" datatype="DOUBLEARRAY" />
|        <res id="RadiationIntensity" datatype="DOUBLEARRAY" />
|        <res id="Radiation" datatype="DOUBLEARRAY" />
|        <res id="Doy" datatype="INT" />
|        <res id="Daylength" datatype="DOUBLE" />
|        <res id="GlobalRadiation" datatype="DOUBLE" />
|      </header>
|      <input id="DateField">CURRENTDATE</input>
|      <input id="MinTempField">AirTemperatureMin</input>
|      <input id="MaxTempField">AirTemperatureMax</input>
|      <input id="RadiationField">GlobalSolarRadiation</input>
|      <input id="Steps">48</input>
|      <input id="Latitude" source="vLatitude" />
|      <input id="RadiationCurve">Sine</input>
|    </transform>

Temperature

Temperature is calculated according to (G) eq. 3.9 for daytime

\(12-d/2 < t_h < 12+d/2\): \[ T_a(t_h) =T_{min} + (T_{max} + T_{min})\sin(\pi \frac{t_h - 12 + \frac{d}{2}}{d + 2p}) \]

and (G) eq. 3.10 for nighttime

\(t_h \leq 12-d/2 \quad\text{or}\quad 12+d/2 \leq t_h\): \[ T_a(t_h) = \frac{T_{min}-T_{sset} e^{-\frac{n}{TC}} + (T_{sset}-T_{min})e^{-\frac{t_h - t_{sset}}{TC}}}{1-e^{-\frac{n}{TC}}} \] where \(T_a\) is the air temperature at hour \(t_h\), \(d, n\) are day- and nightlength, \(p\) is the offset from noon of max temperature and \(TC\) the nocturnal time coefficient. \(T_{sset}, t_{sset}\) are temperature and time at sunsset.

Radiation

If RadiationCurve has the value 'Sine', then the radiation intensitiy follows the curve

\[ I(t) \propto s(t) = \sin(\frac{\pi}{d} (t - (12-\frac{d}{2}))) \]

If it has the value SinBeta the curve (G), eq. 3.2 is used:

\[ I(t) \propto sin\beta(t) = a + b\cos(2\pi \frac{t - 12}{24}) \] where parameters \(a,b\) depend on latitude and daylength. Diurnal Radiation at a timestep \(t_i\) is the radiation accumulated between the previous and actual timestep. \[ R(t_i) = \int_{t_{i-1}}^{t_i}I(t)dt \]

References

(G) Goudriaan, Modeling Potential Crop Growth Processes, 1994, (revised version Nov. 2004)

public class DiurnalSineWeatherTransformer extends
net.simplace.sim.io.resources.FWSimResourceTransformer {
// Public Constructors
public DiurnalSineWeatherTransformer(FWSimSession aSession, Element
aResourceElement, Integer aOrderNumber);
public DiurnalSineWeatherTransformer(FWSimSession aSession, Integer
aOrderNumber);

// Public Instance Methods

public HashMap createVariables(); // Defines
net.simplace.sim.io.FWSimIOAdapter

public FWSimResourceCache getData(FWSimVarMap aVarMap)
throws MissingSimResourceException; // Defines
net.simplace.sim.io.resources.FWSimInputAdapter

standard method from outside

public FWSimResourceCache getData(FWSimVarMap aVarMap, FWSimResourceCache
aResourceCache) throws MissingSimResourceException;

used by test cases

aVarMap variable map
aResourceCache Cached resources (soil data)

returns delivered new data from transformer

public FWSimResourceCache calculateDiurnalValues(int aSteps, double
aLatitude, double aTimeOffset, double timeCoefficient, String
radiationCurve, String aDateField, String aMinTempField, String
aMaxTempField, String aRadiationField, String aProjectID,
FWSimResourceCache aCache) throws MissingSimResourceException;

Calculates Daylengths

aSteps
aLatitude
aTimeOffset
timeCoefficient
radiationCurve
aDateField
aMinTempField
aMaxTempField
aRadiationField
aProjectID id of the project
aCache original weather

returns the new created {@link FWSimResourceCache}

public void updateFields(FWObservable aObservable);
// Defines net.simplace.sim.io.resources.FWSimResourceTransformer

// Protected Instance Methods

protected Object[] MergeKeysAndValues(int aKeyFieldCount, Object aKeys,
HashMap aValues);

aKeyFieldCount
aKeys
aValues

returns

}

Hierarchy: java.lang.Object - net.simplace.sim.io.FWSimIOAdapter (net.simplace.sim.util.FWSimFieldContainer) - net.simplace.sim.io.resources.FWSimInputAdapter - net.simplace.sim.io.resources.FWSimResourceTransformer - DiurnalSineWeatherTransformer