Standard Article

Weather Prediction

Physical Processes

  1. Charles Lin

Published Online: 15 SEP 2006

DOI: 10.1002/9780470057339.vaw007

Encyclopedia of Environmetrics

Encyclopedia of Environmetrics

How to Cite

Lin, C. 2006. Weather Prediction. Encyclopedia of Environmetrics. 6.

Author Information

  1. McGill University, Montréal, Quéebec, Canada

Publication History

  1. Published Online: 15 SEP 2006

Abstract

At the heart of the weather forecast procedure is the numerical weather prediction model. The governing equations are the equations for the three spatial components of momentum, temperature, humidity and mass. The model is made from a spatial discretization of the governing equations on the entire globe using numerical methods (e.g. finite difference and spectral methods). The finite model grid size means that parameterizations of physical processes such as mixing and convective adjustment are necessary. Such models typically have millions of degrees of freedom, and frequently require supercomputers for their efficient solution. The equations are integrated forward in time, again using numerical methods, starting from some initial state. Global forecasts of meteorological quantities such as surface temperature and precipitation are made for up to about two weeks.