SORTIE-ND
Software for spatially-explicit simulation of forest dynamics

Precipitation Climate Change

This behavior changes the value of the Annual Precipitation parameter of the SORTIE plot. This can be used to simulate the effects of climate change. If the run does not have a behavior that uses precipitation, this will have no effect.

Parameters for this behavior

Parameter nameDescription
Precipitation Change - B"B" in the function for varying precipitation through time.
Precipitation Change - C"C" in the function for varying precipitation through time.
Precipitation Change - Precip Lower BoundThe lower bound for allowed precipitation values.
Precipitation Change - Precip Upper BoundThe upper bound for allowed precipitation values.
Update Seasonal Precipitation Proportionally?Whether or not to update seasonal precipitation in the same proportion as annual precipitation.

How it works

The value for plot precipitation is a function of time elapsed since the start of the run, as follows:

P = P1 + B * tC

where:

  • P is the annual precipitation, in mm, at time t
  • P1 is the annual precipitation value at the start of the run, as assigned in the Plot parameters
  • B is the Precipitation Change - B parameter
  • C is the Precipitation Change - C parameter
  • t is the time elapsed, in years, since the start of the run

This value is then given to the Plot object which makes it available to other behaviors in the run.

You can set bounds on the possible precipitation values using the Precipitation Change - Precip Lower Bound and Precipitation Change - Precip Upper Bound parameters. Values are not allowed to go outside these limits.

If you wish, the other seasonal precipitation can be updated along with annual precipitation. They are changed in the same proportion that annual precipitation changes. If you want this behavior, set the Update Seasonal Precipitation Proportionally? parameter to true.

How to apply it

Add this behavior to the run. You can use it alone or in addition to the Temperature Climate Change behavior. You do not need to assign this behavior to trees.