Simulating Soil Moisture & Temperature Regimes with the
Newhall Simulation Model


  1. Soil Moisture & Temperature Regimes
  2. Simulating SMR and STR with the Newhall Simulation Model
  3. How does the NSM work?
  4. Limitations of the model
  5. Applications
  6. Credits
  7. Download the model


Soil Moisture & Temperature Regimes

These are concepts from the USDA Soil Taxonomy system of soil classification. The idea is that the soil climate is a soil property that affects soil use, soil ecology, and soil behaviour. Keys to Soil Taxonomy 8th edition they are defined as follows:

Several soil scientists have suggested that subdivisions of these regimes would be useful for more exact predictions of soil behaviour. One such proposed sub-division was implemented by Van Wambeke in his version of the Newhall model.

These divisions were first used in the following reports:


Simulating SMR and STR with the Newhall Simulation Model

There are two steps:

  1. The Newhall model is run on a time-sequence of monthly climate data, and the daily moisture status (in the control section) and temperature status (at the defined depth) are recorded;
  2. The time-series of moisture and temperature status are summarised according to the rules of the soil moisture & temperature regimes, thereby classifying the site.


How does the model work?

The Newhall Simulation Model for estimating soil moisture & temperature regimes, an explanation by Armand Van Wambeke (PDF, 34Kb)


Limitations of the model

The Newhall model does not take into account:

The model is not based on fundamental soil physics.



This is a list of soil climate studies that have used the Newhall model



Conceptual model
Franklin Newhall, Soil Conservation Service, USDA
FORTRAN implementation
Armand Van Wambeke (RIP), Cornell University
BASIC implementation
Michael Tolomeo, Cornell University
Paul Hastings
Armand Van Wambeke (RIP)
Web page and keeper of the flame
David G Rossiter

Contact: David G. Rossiter;

Last modified: Mon Mar 23 21:09:22 EDT 2020