Download or read book Some Performance Comparisons Between NMC's Spectral Model and the Seven-layer Primitive Equation Model written by Donald G. Marks and published by . This book was released on 1983 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: The performance of NMC's new global spectral model is compared to the performance of the older, seven-layer, grid-point primitive equation model which it replaced. Since it has been in operation since August 1980, mean error statistics may be used to determine this performance. In general, the spectral model shows a distinct improvement in overall forecast skill. The spectral model especially shows an improvement in wave amplitudes and generally stronger flow. Much of this improvement occurs in the longer waves and leads to greatly improved medium range forecasts.