Physical Basis of Weather and Climate Models

Physical Basis of Weather and Climate Models

Portraits of Sir Issac Newton, Rudolf Clausius, Arthur Schuster, Lewis Richardson, Vilhelm Bjerknes, John von Neumann

The modeling of both weather and climate share a deep history and common pedigree based on fundamental laws of physics whose discovery goes back, in some cases, hundreds of years. The equations and calculation methods used in the models can be traced back to the work of giants in the field and direct applications of the fundamental laws of physics, such as

  • Sir Isaac Newton’s laws of motion,
  • Rudolf Clausius’ 1st law of thermodynamics, and
  • Arthur Schuster’s governing equations of radiative transfer.

These scientists deduced the basic laws of physics that are the basis of any good climate and weather model.

In the 20th century, scientists applied these fundamental laws to the atmosphere:

  • Vilhelm Bjerknes, who wrote the equations that we use to forecast the wind in weather and climate models,
  • Lewis Richardson, the father of numerical weather forecasting, and
  • John von Neumann, who led the first team of scientists that successfully ran a numerical forecast model on a computer.

From this lineage we can see how weather and climate models developed from a common heritage, rooted in fundamental physics. Some people, when they hear the word “model”, believe that the equations used to describe physical processes are loosely constrained and can be easily “tweaked” to get whatever answer the modeler wants. That is not the case.