STUDIES IN NUMERICAL WEATHER PREDICTION AND THE DYNAMICS OF FRONTS.
Abstract
The prognostic equations in primitive form for a mathematical model atmosphere, employing two material surfaces, are given. The equations are written in finite difference form, using a generalization of the 'improved Euler-Cauchy method' for ordinary differential equations to partial differential equations. The balance equation is solved to obtain initial winds, by an iteration method which under certain circumstances may not converge, according to Arnason. A way of restoring convergence is proposed. Results of 12 and 24 hour predictions for the two-level model are presented for three cases: with geostrophic initial winds, with balanced initial winds, and with balanced initial winds and orography. The performance of the model is not bad for the first 12 hours, but deteriorates later, probably because of the development of considerable undulations and slope of the upper material surface. This indicates that a redefinition of the upper surface should be made at least after 12 hours. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 01, 1964
- Accession Number
- AD0610127
Entities
People
- Arnt Eliassen
Organizations
- University of Oslo