Weather PredictionECMWF leads the world in global Numerical Weather Prediction with advanced computer observation-analysis modelling technique used to predict the weather. The comprehensive earth-system model developed at ECMWF forms the basis for all the data assimilation and forecasting activities. All the main applications required are available through one integrated computer software system (a set of computer programs mainly written in FORTRAN) called the Integrated Forecast System or IFS. The IFS software is a major European resource representing many years of investment by ECMWF’s Member States. The ECMWF IFS is currently available to the National Meteorological Services of its Member States, and research collaborations are pursued with several European research institutions.

Numerical weather prediction and climate simulations share a common ancestry and also build on the same physical principles, albeit using models with different geospatial resolution and simulation time steps. The climate modelling community relies on NWP developments for the gradual improvements of climate simulations, and ECMWF’s IFS as a world-leading NWP application is very well positioned to contribute to progress in climate modelling. For example, IFS has been chosen as a central building block of the EC-Earth earth system model, being developed by a consortium of organisations from several European countries that aims to implement the emerging concept of seamless prediction of weather and climate. The EC-Earth model is envisaged to be used for various national and European projects and to give input to climate change assessments.

The long-term strategy of ECMWF envisages this trend of increasing resolution and complexity of the forecasting system continuing to bring benefits into the cloud-resolving scales (~ 1km). As the IFS model is currently based on a 16 km horizontal resolution and as the cost of the computations scale approximately like the cube of the resolution increase, this requirement easily leads the IFS into the exascale computing domain. Learn more in this video: