A UB study supports the viability of developing a drought-prediction system in Europe
Researchers of the University of Barcelona, Barcelona Supercomputing Center and the European Commission Joint Research Center (JRC) studied the predictability of summer droughts in Europe. The results of this study, published in the journal Environmental Research Letters, support the predictability of statistical and dynamic systems to predict droughts in Europe from a season to another, which are underused.
Researchers of the University of Barcelona, Barcelona Supercomputing Center and the European Commission Joint Research Center (JRC) studied the predictability of summer droughts in Europe. The results of this study, published in the journal Environmental Research Letters, support the predictability of statistical and dynamic systems to predict droughts in Europe from a season to another, which are underused.
Climate season predictions are important for risk management. But in some cases such as droughts, the existing systems are underused because their predictability is not known. Predicting droughts can be useful to manage water reserves or agriculture as well as in fire management, since it is possible to co-relate both phenomena.
Two systems are currently used to make predictions: an empirico-statistical one, the ensemble streamflow prediction (ESP), which re-lists historical data, and a dynamic one, based on the data from numerical models such as the ones in the European Centre for Medium-Range Weather Forecasts (ECMWF). Both systems combine observations and forecast. According to the study, “the results show that both systems have predictability in four or five monthsʼ time”.
With data from April, researchers made the first prognostic for the following August, and proved that these systems “had a reasonable predictability (correlations between 2.0 and0.5), with higher values in the south-east part of the studied European area”. Moreover, the correlation rises while it reaches August: “For example, the prediction for August made in June had a correlation of about 0.8”, says Marco Turco.
While there are monitoring services for droughts, such as JRCʼs the European Drought Conservatory, or CSICʼs SPEI Global Drought Monitor, “there is not an operational prediction system for droughts in Europe, and our study suggests to implement such a system using databases with almost real-time-observed data”.
Image:
The map on the left shows the drought conditions in May, the one on the right shows the prediction of a moderate drought in August. With the drought conditions observed in May, when some areas in Spain, Italy and Portugal suffered important droughts, a drought-risk prediction for August has been established (see figure), indicating a high probability of moderate-risk in some areas on southern Europe.
Article reference:
Turco et al. «Summer drought predictability over Europe: empirical versus dynamical forecasts». Environmental Research Letters, 2017. https://doi.org/10.1088/1748-9326/aa7859