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

Monthly Climate Data Importer

This behavior allows you to import montly climate data directly. This behavior will then use that data to calculate all of the temperature and precipitation based climate variables used in SORTIE: Annual Precipitation, Mean Annual Temperature, Seasonal Precipitation, and Water Deficit. If you use this behavior, any values entered in the Plot for those variables will be ignored.

Parameters for this behavior

Parameter nameDescription
Available Water Storage in Top 100 cm SoilMaximum available water storage in the top 100 cm of the soil, in mm.
January Radiation (cal/cm2)Global radiation received during the month of January, in cal / cm2.
February Radiation (cal/cm2)Global radiation received during the month of February, in cal / cm2.
March Radiation (cal/cm2)Global radiation received during the month of March, in cal / cm2.
April Radiation (cal/cm2)Global radiation received during the month of April, in cal / cm2.
May Radiation (cal/cm2)Global radiation received during the month of May, in cal / cm2.
June Radiation (cal/cm2)Global radiation received during the month of June, in cal / cm2.
July Radiation (cal/cm2)Global radiation received during the month of July, in cal / cm2.
August Radiation (cal/cm2)Global radiation received during the month of August, in cal / cm2.
September Radiation (cal/cm2)Global radiation received during the month of September, in cal / cm2.
October Radiation (cal/cm2)Global radiation received during the month of October, in cal / cm2.
November Radiation (cal/cm2)Global radiation received during the month of November, in cal / cm2.
December Radiation (cal/cm2)Global radiation received during the month of December, in cal / cm2.
Precipitation for timestep XPrecipitation for each month for that timestep, in mm. You must provide data for all months and all timesteps. SORTIE can read this data from a file - see the Edit Monthly Climate Data Importer Window for more.
Temperature for timestep XMean temperature for each month for that timestep, in degrees C. You must provide data for all months and all timesteps. SORTIE can read this data from a file - see the Edit Monthly Climate Data Importer Window for more.

How it works

Each timestep, this behavior retrieves the monthly precipitation and temperature data and uses them to calculate each climate variable in SORTIE. If the length of the timestep is more than one year, the calculated values will be used for the entire duration of the timestep for those processes that repeat annually.

Radiation values and soil water storage are required to calculate Water Deficit and Seasonal Precipitation. If your run does not require either Water Deficit or Seasonal Precipitation, you can leave those parameters at 0.

Annual Precipitation is calculated by summing the monthly precipitation values for the current timestep.

Mean Annual Temperature is calculated by taking the mean of the monthly temperature values for the current timestep.

Water Deficit is calculated using the same method as the Seasonal Water Deficit behavior.

Seasonal Precipitation is calculated as the sum of soil water storage, growing season precipitation, and potential evapotranspiration (PET) during the non-growing-season portion of the year.

PET for each month is calculated as:

PETi = 0.013 * (Ti/(Ti+15) * (Rs+50)

where:

  • PETi is monthly potential evapotranspiration in mm
  • Ti is monthly temperature in degrees C
  • Rs is the [month i] Radiation (cal/cm2) parameter

If Ti ? 0, then PETi = 0.

Any month where PET > = precipitation is considered part of the growing season.

Seasonal precipitation = AWS + Σ PPTg + Σ PETng

where:

  • PPTg is the precipitation, in mm, for months in the growing season
  • PETng is potential evapotranspiration, in mm, for the months not in the growing season
  • AWS is the Available Water Storage in Top 100 cm Soil parameter

How to apply it

Add this behavior to the run. You do not need to assign this behavior to trees.