New model cycle brings higher resolution
Hólm, Elías ; Forbes, Richard ; Lang, Simon ; Magnusson, Linus ; Malardel, Sylvie
Année de publication
On 8 March 2016, ECMWF introduced a new model cycle of the Integrated Forecasting System (IFS) into operations. Cycle 41r2 represents a significant step forward in accuracy and resolution and, at a grid spacing of 9 km, it is currently the highest-resolution global forecasting system in the world. The main change is an increase in horizontal resolution in most parts of the forecasting system. For high-resolution forecasts (HRES) and ensemble forecasts (ENS) the grid-point resolution is roughly doubled to 9 km and 18 km, respectively, while for the Ensemble of Data Assimilations (EDA) it is tripled to 18 km. In combination with several other scientific and technical changes, this has led to a significant increase in forecast accuracy and computational efficiency. This article sets out the main changes leading to improvements in forecast quality.