Dominik Paprotny

Trends in flood losses in Europe over the past 150 years

Adverse consequences of floods change in time and are influenced by both natural and socio-economic trends and interactions. In Europe, previous studies of historical flood losses corrected for demographic and economic growth (‘normalized’) have been limited in temporal and spatial extent, leading to an incomplete representation of trends in losses over time. Here we utilize a gridded reconstruction of flood exposure in 37 European countries and a new database of damaging floods since 1870. Our results indicate that, after correcting for changes in flood exposure, there has been an increase in annually inundated area and number of persons affected since 1870, contrasted by a substantial decrease in flood fatalities. For more recent decades we also found a considerable decline in financial losses per year. We estimate, however, that there is large underreporting of smaller floods beyond most recent years, and show that underreporting has a substantial impact on observed trends.Flooding may cause loss of life and economic damage, therefore temporal changes need assessment. Here, the authors show that since 1870 there has been an increase in area inundated by floods in Europe, but a reduction in fatalities and economic losses, although caution that smaller floods remain underreported.

Cliff Retreat Induced by Series of Storms at Międzyzdroje (Poland)

ABSTRACT Terefenko, P.; Giza, A.; Paprotny, D.; Kubicki, A., and Winowski, M., 2018. Cliff Retreat Induced by Series of Storms at Międzyzdroje (Poland). In: Shim, J.-S.; Chun, I., and Lim, H.S. (eds.), Proceedings from the International Coastal Symposium (ICS) 2018 (Busan, Republic of Korea). Journal of Coastal Research, Special Issue No. 85, pp. 181–185. Coconut Creek (Florida), ISSN 0749-0208. In Międzyzdroje, a coastal town in Poland, significant cliff retreat has been observed in recent times. It used to be considered mainly a response to storm events with particularly high water levels and wave energy. However, morphology of cliff coasts is shaped not only by the most extreme storm surges or by a number of accompanying processes such as precipitation. Much wider effects are now being linked to the occurrence of series of subsequent storms. This research uses a set of five terrestrial LiDAR surveys carried out between November 2016 and April 2017 to determine short-term cliff erosion associated with two major storm surges and several smaller storms. The surveys covered the whole cliff profile as well as the topography of the adjacent beach. Results indicate a considerable reduction in beach levels as a first important effect. Frequency of the storm events prevented the beach from recovering between the surges, allowing the waves to directly attack the cliff base. Consequently, the cliff foot line retreated up to 4.7 m. This resulted in an erosion volume exceeding 25.000 m3 within 5 sections of the coastal cliff analysed, which are 500 m long in total. This work demonstrates that the development of the coastline is not only directly linked with the rate of erosion at given storm parameters. More importantly, the frequency of extreme events has to be considered.

Characterization of Precipitation through Copulas and Expert Judgement for Risk Assessment of Infrastructure

In this paper two methodologies are investigated that contribute to better assessment of risks related to extreme rainfall events. Firstly, one-parameter bivariate copulas are used to analyze rain gauge data in the Netherlands. Out of three models considered, the Gumbel copula, which indicates upper tail dependence, represents the data most accurately for all 33 stations in the Netherlands. Seasonal variability is noticeable, with rank correlation reaching maximum in winter and minimum in summer as well as other temporal and spatial patterns. Secondly, an expert judgment elicitation was undertaken. The experts’ opinions were combined using Cooke’s classical method in order to obtain estimates of future changes in precipitation patterns. Experts predicted mostly an approximate 10% increase in rain amount, duration, intensity and the dependence between amount and duration. The results were in line with official national climate change scenarios, based on numerical modelling. Applicability of both methods was presented based on an example of an existing tunnel in the Netherlands, contributing to better estimates of the tunnel’s limit state function and therefore the probability of failure.

Measuring Central and Eastern Europe’s Socio-Economic Development Using Time Lags

This paper applies the ‘time lag’ method to a set of social and economic indicators, examining the development of Central and Eastern Europe since the first world war. Originally used to assess technology diffusion, this method allows comparison of levels of development between states and through a long period of time. It presents how many years have elapsed between achieving a certain level of development between countries. The results show that the countries of Central and Eastern Europe have only narrowly converged with a set of 23 highly-developed ‘benchmark’ states. Development in monetary terms (gross domestic product per capita) is the indicator where this region lags most. Employment structure, life expectancy or infant mortality show much smaller lags. Communist states were closest to the West in the 1960s–early 1970s and struggled thereafter. They are still mostly lagging more today than at their peak before transformation despite the progress achieved in absolute terms after the fall of centrally-planned economy.