Multiyear drought assessment for long term rainfall and river flows in Italy

Abstract

<p>Long term time series of daily rainfall and daily river flows are<br>analysed in order to detect the occurrence of drought rich periods<br>through the application of the theory of runs. In detail, we consider<br>the time series of the daily rainfall in Bologna (1813-2019) and daily<br>river flows of the Po River at the closure section (1920-2017). These<br>data sets are a valuable opportunity to assess long term changes of<br>precipitation and water resources availability and the effect of recent<br>climate change. The occurrence of multiyear droughts is a major concern<br>in the context of Italy for the potential impact on irrigation as well<br>as water supply for civil and industrial use. The design suitable<br>adaptation techniques needs to be based on a careful assessment of the<br>probability of multiyear droughts and their intensity. Our results point<br>out the occurrence of critical events along the whole span of the<br>considered observation period, as well as the contingency of a number of<br>recent droughts that point out a condition of potential vulnerability.</p>