SubDailyInterpolation

SubDailyInterpolation is a function module that enables fine-resolution simulation of temperature-driven biological responses by computing sub-daily (e.g., hourly) air temperatures. It does so by interpolating daily minimum and maximum temperatures using a chosen method (e.g., ThreeHourAirTemperature) or HourlySinPpAdjusted, and applying a temperature response function to each sub-daily point, aggregating the result as a sum or average. This allows temperature-dependent processes such as growth, phenology, or respiration to respond more realistically to daily temperature cycles.

Overview

The SubDailyInterpolation model enables simulation of plant and environmental processes that require sub-daily temperature information. It operates by:

  1. Interpolating sub-daily air temperatures using a child model that implements IInterpolationMethod (e.g., HourlySinPpAdjusted or ThreeHourAirTemperature).
  2. Applying a child IIndexedFunction response function to each of the sub-daily temperature values.
  3. Aggregating the responses using either the average or the sum, depending on the selected AgregationMethod (Average or Sum).

This approach is especially valuable in contexts where biological rates (e.g., enzymatic activity or stress responses) are non-linear with respect to temperature.

Inputs

The following inputs are required for SubDailyInterpolation to operate:

  • MetData: A model implementing IWeather, typically the Weather module, which supplies daily Tmin and Tmax.
  • InterpolationMethod: A child model that implements IInterpolationMethod and provides sub-daily temperature estimates (e.g., HourlySinPpAdjusted or ThreeHourAirTemperature).
  • Response: A child model implementing IIndexedFunction, which calculates a biological or physical response for each sub-daily temperature.
  • agregationMethod: A user-configurable enum determining whether the output is the Average or the Sum of the sub-daily responses.

Methodology

The function operates in two stages each day:

  1. Interpolation of Sub-daily Temperatures
    The selected InterpolationMethod model returns a list of sub-daily temperatures:
    \[ T_1, T_2, \dots, T_n \]

  2. Application of Temperature Response Function
    The response function \(f(T)\) is applied to each temperature:
    \[ R_i = f(T_i) \quad \text{for } i = 1 \dots n \]

  3. Aggregation
    Depending on the selected agregationMethod, the result is:

  • Average: \[ R = \frac{1}{n} \sum_{i=1}^n R_i \]
  • Sum: \[ R = \sum_{i=1}^n R_i \]

The result \(R\) becomes the output of the SubDailyInterpolation function for that day.

Events

Events Listened For

Event Purpose
DoDailyInitialisation Triggers the interpolation and response function application each day.

Events Raised To

No events are raised by this function.

Properties

Configurable and Reportable Properties

Property Type Description
agregationMethod enum (Average, Sum) Method used to aggregate sub-daily response values.

Read-Only Reportable Properties

No read-only properties are available for this function.

User Interface

SubDailyInterpolation can be added as a child of a function node in the model tree (e.g., [Phenology]).
Right-click the parent node, select “Add Model…”, and search for SubDailyInterpolation in the Filter Box.

Practical Example

No practical example is provided for this function.

See Also