The ECMWF Scalability Programme: Progress and Plans

The efficiency of the forecasting system on future high-performance computing and data handling systems is considered one of the key challenges for implementing ECMWF’s ambitious strategy. This was already recognised by ECMWF in 2013, and has led to the foundation of the Scalability Programme. The programme aims to address this challenge as a concerted action between the Centre and its Member States, but also draws in the computational science expertise available throughout Europe. This technical memorandum provides an overview of the status of the programme, highlights achievements from the first five years ranging from observational data pre-processing, data assimilation, forecast model design and output data post-processing, and defines the roadmap for the next five years towards a sustainable system that can operate on the expected range of hardware and software technologies. This point in time is crucial because the programme will have a strong focus on implementation and operational benefit in the next period.