Title: Extreme flood frequency trends inferential analysis in Nalon River (Asturias, NW Spain)
Authors: Elena Fernandez Iglesias - University of Oviedo (Spain) [presenting]
Gil Gonzalez-Rodriguez - University of Oviedo (Spain)
Veronica Moro Garcia - University of Oviedo (Spain)
Abstract: Economic losses due to the effect of river floods are one of the largest natural hazard costs in the world. Those are expected to increase due to the growth of population and, according to different studies, to climate change. Several researches show that climate change may alter the frequency and magnitude of river floods in Europe, including Spain. Due to the lack of long records of maximum flows only a few studies at regional scales are available. In order to analyse the flood trends in the Nalon river, the biggest fluvial basin in Northwest of Spain, flow records are extended with other kind of historical flood data to obtain a time series of extreme events, with a return period over 25 years to the period 1938--2020. A simple descriptive analysis shows fairly symmetric distributions for the time between extreme events. In addition, the extreme floods events frequency has been doubled since 2000. A Bootstrap isotonic test in strict sense was applied showing that, indeed, there is an effective increase of the frequency of extreme floods.