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Intensification of precipitation extremes is expected to occur in a warmer climate due to the associated increase in saturation vapour pressure as per the Clausius-Clapeyron (CC) relation. Observational studies of the relationship between extreme precipitation and temperature aim to provide improved understanding of potential changes in precipitation extremes with increasing temperature. However, extreme precipitation-temperature sensitivities have been found to vary significantly across the globe, differing from long term observed trends and modelled projections of systematic increases in extreme precipitation intensities. This thesis examines the relationship between extreme precipitation and temperature to quantify changes in extreme precipitation characteristics in a warming climate. It is shown that previously reported negative precipitation‐temperature sensitivities, suggesting decreases in precipitation intensity with temperature, can be attributed to several shortcomings in the sampling approaches of temperature and precipitation data. Decreasing precipitation-temperature sensitivities at higher temperatures is found to be the result of the decrease in storm duration, and not a decrease in the precipitation rate. Through conditioning precipitation events on storm duration and sampling temperature representative of the atmospheric conditions prevailing the storm, it is shown that precipitation intensities of storms increase with temperature at a rate consistent with CC across all climate zones and storm durations investigated. Analyses of the temporal patterns of precipitation reveal a clear systemic shift towards more front-loaded temporal patterns of precipitation with increasing temperature, contributing to the intensification of embedded bursts. Increased frontal-loading of storms will have implications for how catchments will respond to precipitation with potentially higher flood peaks. With increased moisture availability at higher temperatures, there are concerns of increasing risk of extremes events such as the Probable Maximum Precipitation (PMP). It is shown that historical and future increases in maximum persisting dewpoints will result in substantial increases in operational estimates of the PMP. The practical implications of increasing PMP estimates will require careful consideration in revaluation of flood risk associated with existing and planned dams. The thesis concludes by arguing that hydrological applications need to account for non-stationarity in atmospheric moisture, precipitation intensity, and the temporal patterns of precipitation in a future warmer climate.

Letter of William of Orange to his brother dated 18 oktober 1572

Letter by William of Orange regarding the situation of the Dutch rebels om 18 October 1572.

KCBBE-ALIFE presentation

Now, 10 years after the first plans, we analyse in this paper what has happened with Underground Logistic Systems (ULS). The major question in this paper is: Which barriers and enablers led to the failure of ULS and what ULS spin-offs can be found nowadays? Several factors can be classified as barriers or enablers. The main conclusions that can be drawn are that the opportunities for try-out were too limited; political support could have been gained on higher levels; the costs were too high, the catchment area was too limited; ULS in itself is a very promising system, but there was no one clear goal. In particular, the lack of a thorough and positive business model in combination with a lack of sufficient freight volumes almost immediately guaranteed the failure of the initiative. The spin-offs seem to have taken place in different directions: ranging from rather soft impacts (e.g. scientific knowledge) to more hard developments (adopting and developing transport and tunnelling technologies), and, although difficult to quantify, they are of great value.