Future risk of flooding: an analysis of changes in potential loss of life in South Holland (The Netherlands)

Potential loss of life is considered an important indicator of flood risk. We examine the future development of potential loss of life due to flooding for a major flood prone area in The Netherlands. The analysis is based on projections and spatial distribution of population under a high economic growth scenario and a loss of life model. Results show that the projected population growth in flood prone areas is higher than average in the Netherlands between 2000 and 2040. Due to this effect the potential number of fatalities is projected to increase by 68% on average for 10 different flood scenarios, not including impacts from climate change and sea level rise. Just sea level rise of 0.30 m leads to an average 20% increase in the number of fatalities. The combined impact of sea level rise and population growth leads to an estimated doubling in the potential number of fatalities. Taking into account increasing probability of flooding due to sea level rise and extreme river discharges, the expected number of fatalities could quadruple by 2040. The presented results give a conservative and upper bound estimate of the increase of the risk level when no preventive measures are undertaken. It is found that the consideration of the exact spatial distribution of population growth is essential for arriving at reliable estimates of future risk of flooding.     

Adjusting irrigation abstraction to minimise the impact on stream flow in the East of Scotland

Abstractions of surface and groundwater for irrigation in Scotland are currently subject to control in only two small catchments. Under the terms of the EU Water Framework Directive, it will be necessary to introduce new legislation to control abstractions elsewhere. To help in the development of appropriate policy for Scotland a study has been carried out to examine the significance of irrigation and the effectiveness of different types of control strategies in terms of the economics of potato cropping and stream hydrology in Scotland. This paper presents the findings of the hydrological study and highlights some of the spatial and temporal issues that need to be considered in the selection of control mechanisms, if they are to be successful in achieving objectives for environmental improvement.The study was focussed on two catchments in the east of Scotland, the Tyne and West Peffer. The effectiveness of several different abstraction control strategies was examined to see how stream flows in the catchment would be modified by their implementation. The results of the study demonstrated that the West Peffer catchment in particular is significantly affected by irrigation abstractions. Control mechanisms based on allowable monthly abstraction volumes and flow-based abstraction bans would be of considerable help in restoring stream flows to their natural levels, but would modify the hydrological regime in slightly different ways. A spatial analysis of stream flows demonstrated that implementation of controls based on a single monitoring point may be ineffective at maintaining acceptable levels of flow throughout the catchment and that this may require a tighter control at the monitoring point.     

Renewable energy in remote communities

This research has demonstrated that even in a small urbanised country like Britain, communities can still be remote. The paper analyses the nature of remote settlements and suggests that beyond the rural idyll, there are deprived communities. In order to obtain real data, a study area in the North Pennines was selected. The types of remote communities were evident throughout the study area and one of each type was selected for further study. It became clear that villages with an industrial base had most potential, due to high energy demand, vulnerability and community involvement. A village with a high measure of multiple deprivation and suffering from fuel poverty was chosen for a more detailed investigation. Energy demand profiles were developed and candidate technologies nominated. The latter were tested by filters that assessed fitness for application, robustness and autonomy. The most appropriate combinations of technologies were proposed. The residents and their community representatives were involved in the process and recognised the benefits of the proposals to themselves and others.     

Environmental life-cycle management emerges

Ecological economic thinking leads us to conclude that instead of being mesmerized into inaction by scientific uncertainty over our future, we should acknowledge uncertainty as a fundamental part of the system. We must develop better methods to model and value ecological goals and services and devise policies to translate those values into appropriate incentives. If we continue to segregate ecology and economics, we are courting disaster.     

COMPARATIVE EVALUATION OF STATISTICAL METHODS FOR WATER SUPPLY FORECASTING1

ABSTRACT: While the correlation coefficient and standard error of estimate are frequently used when comparing models of seasonal water yield, the following criteria may be more important in selecting one model from among several alternatives: rationality of the regression coefficients, the distribution of the residual errors, and the correctness of indicators of the relative importance of the predictor variables. These criteria were used to compare seasonal water yield models that were calibrated using multiple regression, stepwise regression, principal components regression, polynomial regression using a principal components rotation, and constrained pattern search. Hydrologic data from the Upper Sevier River basin in southern Utah were used to illustrate the comparative analysis process. The prediction equations used the April-July streamflow volume as the criterion variable.     

Flooding and schools: experiences in Hull in 2007

Hull, a city in the East Riding of Yorkshire, United Kingdom, suffered severe flooding in June 2007, affecting some 8,600 households and most schools. Despite the potential for damage in such disasters, no studies of the effects of floods on teachers and schools in the UK appear to have been published previously. This study analysed the impacts of the floods on teachers in Hull in two stages: first through correspondence with Hull City Council and a mailed questionnaire to 91 head teachers of primary, secondary, and special schools; and second, through in‐depth interviews with head teachers from six flooded schools, representing different degrees of flood experience, and a questionnaire completed by eight teachers from the same schools. The findings reveal the importance and the complexity of the role of the school in the wider community in a time of crisis. The study highlights issues concerning preparedness for floods, support for schools, and flood protection for schools.     

Response to perceived predation threat in fiddler crabs: trust thy neighbor as thyself?

Prey require information if they are to respond to predation threat in a risk-sensitive manner. One way that individuals can obtain this information is through the predator-mediated, threat-induced behavior of conspecifics. We examined such a possibility in a refuge-seeking species, the sand fiddler crab (Uca pugilator). Crabs were either exposed directly to a simulated predation threat (a moving cylinder) or the threat-induced response of a near neighbor. We found that fiddler crabs responded to the flight of their neighbors even when they, themselves, were not privy to the stimulus that induced their neighbors response. However, the wider range of behaviors exhibited by these crabs—which included no reaction, freezing, running back to the burrow entrance, and burrow retreat—suggest that non-threatened crabs either (1) perceived the gravity of the predation threat differently from their directly threatened neighbors and/or (2) engaged in behaviors that allowed them to acquire further information in the face of uncertainty. Conspecific behaviors also had an effect on the hiding duration of crabs, with individuals hiding longer if they saw both the predation threat and the flight of their neighbor. Our results suggest that cues provided by conspecifics can play an important role in guiding the antipredator response of refuge-seeking prey.     

Use of X-ray absorption imaging to examine heterogeneous diffusion in fractured crystalline rocks

Heterogeneous diffusion in different regions of a fractured granodiorite from Japan has been observed and measured through the use of X-ray absorption imaging. These regions include gouge-filled fractures, recrystallized fracture-filling material and hydrothermally altered matrix. With the X-ray absorption imaging technique, porosity, relative concentration, and relative mass of an iodine tracer were imaged in two dimensions with a sub-millimeter pixel size. Because portions of the samples analyzed have relatively low porosity values, imaging errors can potentially impact the results. For this reason, efforts were made to better understand and quantify this error. Based on the X-ray data, pore diffusion coefficients (Dp) for the different regions were estimated assuming a single diffusion rate and a lognormal multirate distribution of Dp. Results show Dp for the gouge-filled fractures are over an order of magnitude greater than those of the recrystallized fracture-filling material, which in turn is approximately two times greater than those for the altered matrix. The recrystallized fracture-filling material was found to exhibit the greatest degree of variability. The results of these experiments also provide evidence that diffusion from advective zones in fractures through the gouge-filled fractures and recrystallized fracture-filling material could increase the pore space available for matrix diffusion. This evidence is important for understanding the performance of potential nuclear waste repositories in crystalline rocks as diffusion is thought to be an important retardation mechanism for radionuclides.