Potential future increase in extreme one-hour precipitation events over Europe due to climate change

Abstract

In this study the potential increase of extreme precipitation in a future warmer European climate has been examined. Output from the regional climate model (RCM) HIRHAM4 covering Europe has been analysed for two periods, a control period 1961-1990 and a scenario 2071-2100, the latter following the IPCC scenario A2. The model has a resolution of about 12 km, which is unique compared with existing RCM studies that typically operate at 25-50 km scale, and make the results relevant to hydrological phenomena occurring at the spatial scale of the infrastructure designed to drain off rainfall in large urban areas. Extreme events with one- and 24-hour duration were extracted using the Partial Duration Series approach, a Generalized Pareto Distribution was fitted to the data and T-year events for return periods from 2 to 100 years were calculated for the control and scenario period in model cells across Europe. The analysis shows that there will be an increase of the intensity of extreme events generally in Europe; Scandinavia will experience the highest increase and southern Europe the lowest. A 20 year 1-hour precipitation event will for example become a 4 year event in Sweden and a 10 year event in Spain. Intensities for short durations and high return periods will increase the most, which implies that European urban drainage systems will be challenged in the future.

Comparison of the impacts of urban development and climate change on exposing European cities to pluvial flooding

“…In the current study, the uncertainty related to climate change is addressed by including different climate scenarios, as well as high/low climate change factors, corresponding to the 90th and 10th percentiles from a set of 10 different GCMs. The resulting change factors derived for future precipitation were found to be in close agreement with the findings of other studies (Larsen et al, 2009;Willems et al, 2012;Sunyer et al, 2015a), although direct comparisons are limited by differences in key variables and methodological assumptions between these studies. These include the choice of climate scenarios, control and scenario periods, and the characteristics of the extreme events.…”

“…Climate change is expected to increase the intensity and frequency of precipitation extremes in both the short and long terms for most regions globally, including Europe (Fowler and Hennessy, 1995;Larsen et al, 2009;Field et al, 2012;Sunyer et al, 2015a). Climate projections generally suggest that the most severe extremes with the shortest (subdaily) durations are likely to be enhanced more than less severe (daily) extremes (Larsen et al, 2009;Arnbjerg-Nielsen, 2012).…”

“…Climate projections generally suggest that the most severe extremes with the shortest (subdaily) durations are likely to be enhanced more than less severe (daily) extremes (Larsen et al, 2009;Arnbjerg-Nielsen, 2012). In this analysis, we consider two different climate scenarios: RCP 4.5 and RCP 8.5.…”

Downscaling of Short-Term Precipitation Time Series for Climate Change Impact Assessment

“…Both theoretical considerations [1] and climate model projections [2,3] generally support this hypothesis. This implies an increased load on sewer systems with potential consequences in terms of increased overflow volumes and flood risks [4].…”

Assessment of the relation between atmospheric precipitation and rainwater runoff for various urban surfaces

“…Turning urban areas into impervious surfaces through the process of urbanisation is one of the main factors causing the appearance of excessive volumes of rainwater runoff [ARNOLD, GIBBONS 1996;JENNINGS, JARNAGIN 2002]. That phenomenon is amplified by the global climate change that causes the occurrence of weather anomalies, including intense atmospheric precipitations [BLAIR et al 2014;LARSEN et al 2009]. The increasing character of the phenomenon described above has had an impact on the directions of research in the field of urban hydrology, and the study of relations between the value of surface runoff and the degree of imperviousness of surfaces has become the subject-matter of numerous research works.…”