The Surface Heat / TemperatureExchange frame provides a drop down list for Surface Heat Exchange Submodels, with options including: Atmospheric linkage, Full Heat Balance, External Equilibrium Temperature, Constant Equilibrium Temperature and Equilibrium temperature (CE-QUAL-W2 method, EFDC_DSI only).

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The EFDC_DSI version of the model has two different approaches for the bed heat sub-models. If the standard EFDC full heat balance (ISTOPT(2)=1) sub-model is used, the water/sediment bed heat exchange model of the pre-GVC version is used. If the user has selected the equilibrium temperature sub-model (ISTOPT(2)=4) then the bottom heat exchange is computed using the heat exchange coefficient and the user can assign spatially varying sediment thicknesses and initial temperatures using the TEMB.INP file.
Various atmospheric parameters can be adjusted using the Settings button in the Heat/Temperature form. An example of the Atmospheric Parameters values box is shown in Heat Temperature Figure 1. The parameters shown in Figure 1 change slightly depending on which heat sub-model is being used.

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Figure 1  Atmospheric Parameters.

Evaporation Options

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