Lessons from calibrating a global flood forecasting system

Lessons from calibrating a global flood forecasting system

Contributed by Feyera Hirpa, University of Oxford. Hydrological models are key tools for predicting flood disasters several days ahead of their occurrence. However, their usability as a decision support tool depends on their skill in reproducing the observed streamflow. The forecast skill is subject to a cascade of uncertainties originating from errors in the models’ structure, parametrization, initial conditions and meteorological forcing. The Global Flood Awareness System (GloFAS) is an operational flood forecasting system that produces ensemble streamflow forecasts with…

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Nice hydrographs for everyone, from everyone: Introducing eWaterCycle II

Nice hydrographs for everyone, from everyone: Introducing eWaterCycle II

Contributed by Rolf Hut, TU Delft. “Nice hydrographs! Can you now compare your model to ‘that other hydrology groups model’?” The PhD student suppresses the urge to roll her eyes. Her supervisor is asking her to go back into code-hell. That other model is written in Fortran and she works in Python. It took her two months to get the Python model used in her group running in the first place. Realizing she needed to install an obtuse library on…

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“One thing you need to know about seasonal forecasts”

“One thing you need to know about seasonal forecasts”

Contributed by Rachel Bazile, Marie-Amélie Boucher and Chris White. “It is that they have no skill…” This is how Matt Newman from NOAA’s ESRL referred to seasonal forecasts in his opening presentation at the Second International Conference on Subseasonal to Seasonal (S2S) / Seasonal to Decadal (S2D) Prediction. Organized by NCAR, the meeting which was held from Sept. 17 to 21 in Boulder, Colorado, had gathered more than 300 international scientists from both the S2S and S2D prediction communities… but…

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Acqua Alta: Flooding and Flood Forecasting in Venice, Italy

Acqua Alta: Flooding and Flood Forecasting in Venice, Italy

Contributed by Luigi Cavaleri, Institute of Marine Science (CNR), Venice, Italy. Venice is sinking at a rate of 1-2 mm/y. Combined with the present rate of sea level rise, ~3mm/y, this leads to ever more critical conditions for the possibility of flooding. With half of the city now no more than 80 cm above the present mean sea level and a tidal spring excursion of about 1 metre, any small surge will imply flooding in large parts of the city. A…

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How writing an article can come out of the blue (KGE on log-transformed flows: a bad idea?)

How writing an article can come out of the blue (KGE on log-transformed flows: a bad idea?)

Contributed by Léonard Santos (Irstea, France). It is common to read articles in which the Kling and Gupta Efficiency (KGE, Gupta et al., 2009) or its modified version (KGE’, Kling et al., 2012) are used as a metric to evaluate the quality of streamflow simulations. They are often seen as a solution to substitute the Nash and Sutcliffe Efficiency (NSE, Nash and Sutcliffe, 1970). However, are these two criterion totally comparable? Can the KGE be used exactly in the same…

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