Application of Ensembles in Flood Forecasting

A major research challenge of the 21st century is to provide early warning for floods with potentially disastrous consequences. In 2007 floods killed 8349 people, affected 164 million and caused damage in the excess of 21 billion US$ (EM Dat, 2007). Early flood warning several days in advance could provide civil protection authorities and the public with vital preparation time and could reduce the socio-economic impacts of flooding. Unfortunately, precipitation forecasts, in most cases the driving factor for floods, are highly uncertain. In a study based on forecasts from the European Centre for Medium-Range Weather Forecasts, Buizza et al. (1999) showed that although generally the skill in weather forecasting has increased to 5-6 days, e.g. for temperature, it is only of the order of 2-3 days for precipitation. For extreme rainfalls which are of special interest to flood forecasters, the forecasting time for skilled forecasts decreases even further. The lead time for skilful precipitation forecasting can be, however, extended by exploring ensemble prediction systems (EPS). The main benefit of medium-range probabilistic flood forecasts for hydrological services is the increased lead time for warnings of a flood event.

THIELEN DEL POZO Jutta;  BARTHOLMES Jens;  PAPPENBERGER Florian; 

2008-07-21

Shinfield Park

JRC44008

http://www.ecmwf.int/publications/library/do/references/list/12052007,    http://www.ecmwf.int/publications/library/ecpublications/_pdf/workshop/2007/Ensemble_prediction/Thielen.pdf,    https://publications.jrc.ec.europa.eu/repository/handle/JRC44008,