Modeling, parameterization, and forecasting of weather systems in the terrestrial atmosphere



Significant progress has been achieved during recent years, especially since the FGGE (First “Global Atmospheric Research Programme” Global Experiment), in numerical weather forecast up to 3–8 days ahead on the global scale. This is especially true for the large-scale features of the atmospheric circulation, and the progress is best measured by objective forecast scores for the 500-mb pressure level. However, the progress in the forecast of well-defined weather systems and of associated weather elements, such as low-level wind, surface temperature, cloudiness, and precipitation (which have the most practical and economical implications), has been relatively slower. It is felt that a lot remains to be gained in this field by a better use of basic modeling efforts aimed, for example, at understanding the physical mechanisms within specific weather systems, and by the correlative development of advanced parameterization techniques.