17th HEPEX Webinar: 2004-2014 – The rise of the meteorological ensembles in the HEPEX decade
The Webinars are back after a small break over the summer. First out for the season is one of the founding fathers of HEPEX, Roberto Buizza.
Speaker: Roberto Buizza, ECMWF
Date and time: Tuesday, September 30, 2014 3:00 pm GMT Summer Time (UTC+01:00)
Preview of the seminar:17th_HEPEX_Webinar_Buizza
Abstract: In 2004, ECMWF hosted the first workshop that discussed the proposal for an International Hydrological Ensemble Prediction Experiment (HEPEX). This is how HEPEX started, with one of its main objectives being to demonstrate how to produce reliable “engineering quality” hydrological ensemble forecasts that can be used to assist the water resources sector to make decisions that have important consequences for the economy and for public health and safety. Before HEPEX, no one was producing daily, operational hydrological ensemble prediction, while weather forecasters were already using ensemble-based, probabilistic forecasts. Today, in 2014, also thanks to HEPEX, many centres, including ECMWF and NOAA, produce operational, ensemble-based, probabilistic hydrological forecasts. Progress has been made because the hydrological and meteorological communities have reached out, exchanged ideas and worked together. Developments in this area have been possible also thanks to the progress of the quality of the meteorological ensembles.
In this talk, first I will discuss why ensembles are more valuable than single forecasts and briefly review how ensembles are now used in meteorology to estimate the probability distribution function of initial and forecast states. Then I will show how the ECMWF operational ensembles perform, and I will conclude by presenting how we are planning to further improve their performance.