Package net.simplace.sim.components.soil.temperature

Class STMPsimCalculator

java.lang.Object
net.simplace.sim.model.FWSimComponent
net.simplace.sim.components.soil.temperature.STMPsimCalculator
All Implemented Interfaces:
net.simplace.sim.util.FWSimFieldContainer
public class STMPsimCalculator extends net.simplace.sim.model.FWSimComponent
Calculates the soil temperature in n layers depending on climate and soil conditions.

STMP

Soil temperature of the soil layers is calculated using the formula:

\[ \begin{eqnarray} STMP&=&LAG \cdot STMP0+(1.0-LAG) \cdot (FZ \cdot (AVT-DST0)+DST0) \label{stmp} \end{eqnarray} \]

Reference:

Williams, J.R., Izaurralde, C.A., 2005. The APEX model, Blackland Research Center Reports, Vol. 2. Blackland Research Center, USDA, Temple, Texas, USA

STMP calculation

Daily average soil temperature at the center of each soil layer is simulated for use in nutrient cycling and hydrology. The basic soil temperature equation is shown in Eq \(\eqref{stmp}\) with

\[ \begin{eqnarray} FZ&=&\frac{X1}{X1+\exp(-0.8669-2.0775 \cdot X1)} \\ X1&=&0.5 \cdot \frac{Z(l)+Z(l-1)}{DD} \label{x1} \end{eqnarray} \]

where STMP is the soil temperature at the center of a soil layer in °C, Z is the depth from the surface to the bottom of the soil layer l in m, LAG is a coefficient ranging from 0.0 to 1.0 that allows proper weighting of yesterday's temperature STMP0, AVT is the long-term average annual air temperature at the site, DST0 is the soil surface temperature, and DD is the damping depth in m. Thus, given yesterday's temperature, Eq \(\eqref{stmp}\) estimates today's temperature as a function of soil surface temperature, depth, and a lag coefficient. It is assumed that the temperature remains almost constant at the damping depth and is approximately AVT. Obviously, Eq \(\eqref{stmp}\) makes near surface temperatures a strong function of DST0. As depth increases, AVT has more influence until finally at the damping depth, the temperature is within 5% of AVT.

The damping depth is a function of soil bulk density and water content as expressed in the equation

\[ \begin{eqnarray} DD&=&DP \cdot \exp(\ln(\frac{0.5}{DP}) \cdot \frac{1.-WC}{1.+WC} \cdot 2) \\ DP&=&1.+\frac{2.5 \cdot ABD}{ABD+\exp(6.53-5.63 \cdot ABD)} \\ WC&=&0.001 \cdot \frac{ST}{Z(n) \cdot (0.356-0.144 \cdot ABD)} \end{eqnarray} \]

where DP is the maximum damping depth for the soil in m, ABD is the average soil bulk density of the profile in t m-3, n is the number of soil layers in the profile, and ST is the water stored in the profile in mm.

To complete the solution of Eq \(\eqref{stmp}\), the soil surface temperature must be estimated. The first step is to estimate the bare soil surface temperature.

\[ \begin{eqnarray} DST&=&0.5 \cdot (TMX+TMN)+(TMX-TMN) \cdot \frac{RA \cdot (1.0-AB)-14.}{20} \label{dst} \end{eqnarray} \]

The first term in \(\eqref{dst}\) estimates bare soil temperature to equal average daily air temperature. The second term adjusts the basic estimate using the net radiation as a driver and half the temperature difference as a range. The adjustment changes signs at a net radiation value of 14 MJ m-2 d-1. If the soil surface is not bare, the surface temperature can be affected considerably by the amount of cover (crop residue or snow). This effect can be simulated by combining the estimated bare surface temperature for the day with the previous day's temperature in the second soil layer (the top 10 mm layer is considered too thin for this purpose).

\[ \begin{eqnarray} DST0&=&(1.-BCV) \cdot DST+BCV \cdot STMP(2)) \end{eqnarray} \]

where DST0 is the final estimate of soil surface temperature in °C and BCV is a lagging factor for simulating residue and snow cover effects on surface temperature.

This is done using the SnowCoverCalculator SimComponent that can therefore be linked using the outputted SoilTemperature array and delivering the SoilSurfaceTemperature (DST0)

Author:
Andreas Enders, Gunther Krauss

Component Variables

Content TypeNameDescriptionData TypeUnitMin ValueMax ValueDefault Value
constantcABDMean bulk densityDOUBLEt/m31.04.02.0
constantcAVTConstant Temperature of deepest soil layer - use long term mean air temperatureDOUBLE°C-10.020.0-
constantcDampingDepthInitial value for damping depth of soilDOUBLEm1.520.06.0
constantcFirstDayMeanTempMean air temperature on first dayDOUBLE°C-40.050.0-
constantcSoilLayerDepthDepth of soil layerDOUBLEARRAYm0.0320.0-
inputiDoInitializeSwitch to re-initialize the model with initial values.BOOLEAN1--false
inputiSoilSurfaceTemperatureTemperature at soil surfaceDOUBLE°C1.520.0-
inputiSoilWaterContentWater content, sum of whole soil profileDOUBLEmm1.520.05.0
stateSoilTempArrayArray of soil temperatures in layers DOUBLEARRAY°C-40.050.0-
raterSoilTempArrayRateArray of daily temperature changeDOUBLEARRAYdegree_Celsius_per_day-20.020.0-

  • Nested Class Summary

    Nested classes/interfaces inherited from class net.simplace.sim.model.FWSimComponent

    net.simplace.sim.model.FWSimComponent.TEST_STATE

  • Field Summary

    Fields inherited from class net.simplace.sim.model.FWSimComponent

    iFieldMap, iFrequence, iInputMap, iJexlRule, iMasterComponentGroup, iName, iOrderNumber, isComponentGroup, iSimComponentElement, iSimModel, iVarMap

  • Constructor Summary

    Constructors
    Constructor
    Description
    STMPsimCalculator()
    Empty constructor used by class.forName()

  • Method Summary

    Modifier and Type
    Method
    Description
    protected net.simplace.sim.model.FWSimComponent
    clone(net.simplace.sim.util.FWSimVarMap aVarMap)
     
    HashMap<String,net.simplace.sim.util.FWSimVariable<?>>
    createVariables()
    create the FWSimVariables as interface for this SimComponent
    HashMap<String,net.simplace.sim.util.FWSimVariable<?>>
    fillTestVariables(int aTestIndex, net.simplace.sim.model.FWSimComponent.TEST_STATE aDefineOrCheck)
    called for single component test to check the components algorithm.
    protected void
    init()
    initializes the fields by getting input and output FWSimVariables from VarMap
    protected void
    process()
    process the algorithm and write the results back to VarMap TMX = Maximum air temperature at 2 m (°C) TMN = Minimum air temperature at 2 m (°C) RA = RA(t) = Mean daily solar radiation on day t (kJ/m2*d) PREC = Precipitation on day t (mm) CV = Crop residues plus above ground biomass (kg/ha) SNO = Water content in snow layer (mm) SW = ST(t) = Soil water stored in the soil profile at day t (mm) SLA = Leaf area index (m*m-1) PEVAP = Potential soil evaporation (mm)
    protected void
    reInitialize()
     

    Methods inherited from class net.simplace.sim.model.FWSimComponent

    addVariable, bind, checkCondition, createSimComponent, createSimComponent, createSimComponent, createSimComponent, doProcess, getConstantVariables, getContentType, getCreateFormXML, getDescription, getEditFormXML, getFieldMap, getFrequence, getFrequenceRuleScript, getInputs, getInputVariables, getMasterComponentGroup, getName, getOrderNumber, getOutputVariables, getVariable, getVariableField, getVarMap, initialize, isConditionCheck, isVariableAvailable, performLinks, performLinks, readInputs, removeVariable, reset, runComponentTest, setVariablesDefault, toComponentLinkingXML, toDocXML, toGroupXML, toOutputDefinitionXML, toResourcesDataXML, toResourcesDefinitionXML, toString, toXML, writeVarInfos

    Methods inherited from class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

  • Constructor Details

    • STMPsimCalculator

      public STMPsimCalculator()
      Empty constructor used by class.forName()

  • Method Details

    • createVariables

      public HashMap<String,net.simplace.sim.util.FWSimVariable<?>> createVariables()
      create the FWSimVariables as interface for this SimComponent
      Specified by:
      createVariables in interface net.simplace.sim.util.FWSimFieldContainer
      Specified by:
      createVariables in class net.simplace.sim.model.FWSimComponent
      See Also:
      • FWSimComponent.createVariables()

    • init

      protected void init()
      initializes the fields by getting input and output FWSimVariables from VarMap
      Specified by:
      init in class net.simplace.sim.model.FWSimComponent
      See Also:
      • Z(IndexOfSoilLayer) = Depth to the bottom of the soil layer L (m) ABD = Average bulk density over all layers in the soil profile (t m-3) AVT = Annual mean air temperature at 2 m (°C) STMP = SoilTemperature of layer (°C)

    • reInitialize

      protected void reInitialize()

    • process

      protected void process()
      process the algorithm and write the results back to VarMap TMX = Maximum air temperature at 2 m (°C) TMN = Minimum air temperature at 2 m (°C) RA = RA(t) = Mean daily solar radiation on day t (kJ/m2*d) PREC = Precipitation on day t (mm) CV = Crop residues plus above ground biomass (kg/ha) SNO = Water content in snow layer (mm) SW = ST(t) = Soil water stored in the soil profile at day t (mm) SLA = Leaf area index (m*m-1) PEVAP = Potential soil evaporation (mm)
      Specified by:
      process in class net.simplace.sim.model.FWSimComponent
      See Also:
      • FWSimComponent.process()

    • fillTestVariables

      public HashMap<String,net.simplace.sim.util.FWSimVariable<?>> fillTestVariables(int aTestIndex, net.simplace.sim.model.FWSimComponent.TEST_STATE aDefineOrCheck)
      called for single component test to check the components algorithm. aParamIndex: Used to set up different test cases. Start with 0 - result check with 1 aso
      Specified by:
      fillTestVariables in class net.simplace.sim.model.FWSimComponent
      See Also:
      • net.simplace.sim.util.FWSimFieldContainer#fillTestVariables(int aParamIndex, TEST_STATE aDefineOrCheck)

    • clone

      protected net.simplace.sim.model.FWSimComponent clone(net.simplace.sim.util.FWSimVarMap aVarMap)
      Specified by:
      clone in class net.simplace.sim.model.FWSimComponent
      See Also:
      • FWSimComponent.clone(net.simplace.sim.util.FWSimVarMap)