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Category: data systems

Data Drought and Data Flood

Data Drought and Data Flood

Contributed by Mark Trigg*.  It’s hot, and very, very dry. The rains have failed, and the animals are dying. Around the table people are concerned that it will be people dying next. The cycle seems to repeat every 10 years and the response is exactly the same, every time – we must do something and save lives. “Drill more boreholes and put in big pumps and generators”, someone cries, “no matter the cost!”. A timid voice rises above the ongoing…

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OpenIFS@home: Using citizen science to improve our understanding of weather and hydrological forecasts

OpenIFS@home: Using citizen science to improve our understanding of weather and hydrological forecasts

The history of HEPEX is deeply connected to ensemble forecasting and uncertainty analysis. Indeed, none of us could even imagine a forecast without uncertainties (apart from McFool). One direction of research is to investigate the value in improving forecasts using a coupled system and truly understand the interactions between the atmosphere and the land surface whilst analysing the associated uncertainties. However, any analysis is limited by the resources one has available. To run a large number of ensembles, one would…

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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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Flood memory and historical marks of high waters

Flood memory and historical marks of high waters

Contributed by Maria-Helena Ramos (Irstea, France) Last year, the Hepex Portal published a blog post by Richard Davies from floodlist.com about the UK and Ireland floods in December 2015 and January 2016. When navigating through the floodlist website, I found a page dedicated to flood and high water marks (here). I have always found these marks indicating the level reached by the waters of a river (or any other waterbody) after a flood event to be fascinating. It is not…

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Crowdsourced data for flood hydrology – Interview with flood chasers in France and Argentina

Crowdsourced data for flood hydrology – Interview with flood chasers in France and Argentina

Contributed by MH Ramos, member of the IRSTEA Columnist Team A recent paper published in the Journal of Hydrology has drawn my attention: Crowdsourced data for flood hydrology: Feedback from recent citizen science projects in Argentina, France and New Zealand. The paper deals with the use of information from social media in applied sciences and operations, with a focus on collecting photos and videos  to better assess river flows and to improve flood mapping after severe events. It prompts reflections on the way qualitative and quantitative data can…

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