Samuele Giampietro

Per la serie “Environmental Meteorology Seminar”, vi segnaliamo il seminario di Fatima Pillosu (European Centre for Medium-range Weather Forecasts and University of Reading, Reading, UK) dal titolo: “ecPoint, post-processing of global ensemble rainfall forecasts: current efforts and future challenges to improve the prediction of extreme localized rainfall events and flash floods at global scale”. Il seminario si terrà Giovedì 20 Ottobre 2022 alle ore 14:30, online attraverso la piattaforma Zoom (https://unitn.zoom.us/j/85796377450 – Meeting ID: 857 9637 7450, Passcode: 182580) e in presenza sarà riprodotto nell’Aula 2Q del Dipartimento di Ingegneria Civile, Ambientale e Meccanica (DICAM) presso l’Università degli Studi di Trento, in Via Mesiano 77 (38123, Trento). Vi lasciamo un abstract e la biografia di Fatima Pillosu in basso: Abstract ECMWF has always been at the forefront of numerical weather prediction (NWP) model development, often ranking as one of the world’s leading centres for weather prediction. ECMWF’s Integrated Forecasting System (IFS) covers the global domain, different time horizons (e.g., medium-range, sub-seasonal and seasonal), and consists of several components (e.g., the atmospheric general circulation model, the ocean wave model, the land-surface model, and the perturbation models for data assimilation and generation of forecast ensembles). Any NWP model divides the Earth’s surface into grid boxes and predicts one value (e.g., for rainfall or temperature) per grid box. The sizes of such grid-boxes vary depending on the model, from 1 to 5 km for regional high-resolution models to 10 to 50 km for global lower-resolution models. At ECMWF, great efforts are made to consistently increase the resolution of their NWP models to provide their users with better forecasts for specific locations, especially for extreme events (e.g., wind gusts, convective storms, and flash floods). Currently, the global ensemble forecasts (ENS) are provided at 18 km and are expected to go to 9 km next year. However, if weather varies markedly within a grid box or the predictability of the atmosphere is low, forecasts for specific sites will inevitably fail due to biases or representativeness errors in the model. By post-processing the raw NWP forecasts, it is possible to provide better predictions for specific locations. ecPoint has been one of the first post-processing projects at ECMWF, mainly to anticipate sub-grid variability and biases in rainfall forecasts. Currently, ecPoint provides global point-scale rainfall forecasts up to day 10 to ECMWF users worldwide. Furthermore, ongoing investigations are carried out on how to use ecPoint products to predict one of the most devastating natural hazards: flash floods. The seminar will provide an overview of the ecPoint post-processing technique. It will also discuss the research behind the definition of a global layer in the GloFAS platform that will use ecPoint forecasts for the global prediction of flash floods at medium ranges, which hopes to help mainly humanitarian actions in developing countries. Bio Fatima Pillosu is a researcher at the European Centre for Medium-range Weather Forecasts (ECMWF, Reading, UK) and a PhD student at the University of Reading (Reading, UK). After obtaining a bachelor’s degree in civil engineering at the University of Cagliari, she specialised in hydrology through an MSc in Hydraulic Engineering at the University of Cagliari with a thesis that analysed the change in frequency of extreme rainfall events and flash floods in Sardinia. This latter work encouraged her to gain experience in meteorological science, which led her to a 1-year internship at ECMWF in 2016. The project focused on developing an innovative post-processing technique (called ecPoint) to determine the degree of sub-grid variability and biases in short- to medium-range rainfall forecasts. In 2019, this research project became operational at ECMWF, providing global point-scale rainfall forecasts to ECMWF users worldwide. In 2017, she also started a PhD at the University of Reading to investigate the utility of such new post-processed rainfall forecasts for hydrological predictions, focusing mainly on flash flood forecasting. This series of seminars is primarily targeted to Students attending our double-degree programme of MSc in Environmental Meteorology [1]. However all those who are interested are more than welcome to join!