Application of Multi-Processors to Operational Analysis and Forecasts at the French Weather Service

Abstract

The aim of the French Weather Service is, for a major part, to make and deliver products about the current meteorological situation and its expected evolution up to a few days, with an update twice daily. These features have always required a lot of computing facilities, and especially a high-level computing power. For these reasons, the French operational weather models have been running on a Cray-1S since January 1985. This machine is a vector and remote computer, which is shared with other French scientists in the framework of an economic group (G.C.C.V.R.). However, this computer has shown its limits (!) and will be replaced in the first quarter of 1987 by a Cray-2, which is also a vector computer, quicker in this mode, including a much larger core memory (256 MW instead of 1) and 4 processors, with the possibility of running multitasked jobs. As this feature is especially well-suited to run time-critical and big codes, we are particularly concerned with use of multi-tasking for our operational suite.