Summer 2018 in Europe: did the EFAS seasonal outlook predict low river flows?

Summer 2018 in Europe: did the EFAS seasonal outlook predict low river flows?

— this post is jointly published on the blogs of HEPEX and the European Drought Centre — Contributed by Louise Arnal (ECMWF and University of Reading), Shaun Harrigan (ECMWF) & David Lavers (ECMWF). Summer 2018 in Europe was remarkable from a hydroclimate perspective, with large regions experiencing persistent dry conditions, very little to no rainfall for extended periods, a series of heatwaves with record-breaking temperatures and numerous wildfires (in the UK, Sweden, Greece, Spain, Portugal, Latvia and Germany, among others)….

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GloFAS-Seasonal: Global Scale Seasonal River Flow Forecasts

GloFAS-Seasonal: Global Scale Seasonal River Flow Forecasts

Contributed by Rebecca Emerton. My PhD research looks into how we can provide earlier indications of flood hazard at the global scale. One way of doing this is through seasonal forecasts of high (or low) river flow. Seasonal forecasts are designed to provide an early indication that a given variable, in this case river flow, will differ from normal in the coming weeks or months. While many operational centres produce seasonal forecasts of meteorological variables, operational seasonal forecasts of hydrological…

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Skilful seasonal forecasts of streamflow over Europe?

Skilful seasonal forecasts of streamflow over Europe?

Contributed by Louise Arnal, University of Reading & ECMWF Editor’s Note: Don’t miss the brilliant cartoon summary at the bottom of this post! Over recent decades, seasonal streamflow forecasting methods have evolved and diversified, reflecting changes in our scientific understanding of streamflow predictability on seasonal timescales and our increasing computer power. The first operational model-based ensemble seasonal streamflow forecast, called the ESP1,2 (ensemble streamflow prediction), relies on the correct knowledge of the initial hydrological conditions (IHC; i.e. of snowpack, soil…

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Hydropower management in Brazil and water forecasts – Interview with Alberto Assis dos Reis

Hydropower management in Brazil and water forecasts – Interview with Alberto Assis dos Reis

Alberto is an engineer and hydrologist at Cemig, a Brazilian power company headquartered in Belo Horizonte, the capital of the state of Minas Gerais, and is currently starting a PhD work at the Federal University of Minas Gerais (UFMG). His PhD project involves also collaboration with three other organizations in Europe, strongly involved in Hepex: Irstea (France), Deltares (The Netherlands) and ECMWF (UK). He was recently visiting these organizations and, when he came to France, I took the opportunity to…

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How suitable is quantile mapping for post-processing GCM precipitation forecasts?

How suitable is quantile mapping for post-processing GCM precipitation forecasts?

Contributed by QJ Wang, University of Melbourne* Back in September 2015 at the highly successful HEPEX Seasonal Hydrological Forecasting Workshop at SMHI in Norrkoping, Sweden, I heard a number of presentations and saw posters on the use of quantile mapping for post-processing or downscaling GCM precipitation forecasts. While quantile mapping was well known to be highly effective in bias correction, I was concerned that some of its limitations might not have been apparent to some people. After discussing with Andy…

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