Saskia E. Werners

Dealing with Uncertainty in Flood Management Through Diversification

This paper shows, through a numerical example, how to develop portfolios of flood management activities that generate the highest return under an acceptable risk for an area in the central part of the Netherlands. The paper shows a method based on Modern Portfolio Theory (MPT) that contributes to developing flood management strategies. MPT aims at finding sets of investments that diversify risks thereby reducing the overall risk of the total portfolio of investments. This paper shows that through systematically combining four different flood protection measures in portfolios containing three or four measures; risk is reduced compared with portfolios that only contain one or two measures. Adding partly uncorrelated measures to the portfolio diversifies risk. We demonstrate how MPT encourages a systematic discussion of the relationship between the return and risk of individual flood mitigation activities and the return and risk of complete portfolios. It is also shown how important it is to understand the correlation of the returns of various flood management activities. The MPT approach, therefore, fits well with the notion of adaptive water management, which perceives the future as inherently uncertain. Through applying MPT on flood protection strategies current vulnerability will be reduced by diversifying risk.

Individuals Matter: Exploring Strategies of Individuals to Change the Water Policy for the Tisza River in Hungary

This paper offers a novel interpretation of the introduction of floodplain rehabilitation and rural development into the water policy for the Tisza River in Hungary. It looks at the role of individuals and the strategies that they used to bring about water policy change. Five strategies are explored: developing new ideas, building coalitions to sell ideas, using windows of opportunity, playing multiple venues and orchestrating networks. Our discussion on the importance of each strategy and the individuals behind it is based on interviews, group discussions and a literature review. The international and political attention sparked by a series of floods, dike failure and a major cyanide spill, which preceded national elections, opened a window of opportunity for launching ideas. A new regional coalition successfully introduced floodplain rehabilitation into the water policy arena. Our analysis emphasizes the importance of a responsible civil servant who recognizes a new policy idea at an abstract level and a credible regional coalition that advocates the new idea regionally.

Cross-border organisations as an adaptive water management response to climate change: the case of the Guadiana river basin

In this paper we analyse the role played by cross-border organisations in the Guadiana river basin in Iberia, and the extent to which new emerging institutional arrangements carry on adaptive management practice as a response to mounting climate change risks in the river basin. Particular attention is paid to the new transboundary agencies, as promoted by the EU INTERREG programmes, and their potential for mainstreaming climate change considerations into Guadiana river basin development strategies. Results indicate that the penetration of climate change concerns into regional development policies requires a better integration of different policies and improved connectivity and coordination between multiple actors operating across sectors, and at different spatial scales. We argue that the emergence of new transboundary agencies capable of performing these bridging functions is a vital ingredient for building climate adaptive capacity in these cross-border regions.

Construction area expansion in relation to economic-demographic development and land resource in the Pearl River Delta of China

Since 1979, the Pearl River Delta (PRD) of China has experienced rapid socioeconomic development along with a fast expansion of construction area. Affected by both natural and human factors, a complex interdependency is found among the regional changes in construction area, GDP and population. A quantitative analysis of the four phases of the regional land use data extracted from remote sensing images and socioeconomic statistics spanning 1979 to 2009 demonstrates that the proportion of construction area in the PRD increased from 0.5% in 1979 to 10.8% in 2009, accompanied with a rapid loss of agricultural land. An increase of one million residents was associated with an increase of GDP of approximately 32 billion yuan before 2000 and approximately 162 billion yuan after 2000. Because the expansion of construction area has approached the limits of land resource in some cities of the PRD, a power function is found more suitable than a linear one in describing the relationship between GDP and construction area. Consequently, the Logistic model is shown to provide more accurate predictions of population growth than the Malthus model, particularly in some cities where a very large proportion of land resource has been urbanized, such as Shenzhen and Dongguan.

Managing the current and future supply of ecosystem services in the Hungarian and Romanian Tisza River Basin

Ecosystem services that sustain human well-being depend on the continued functioning of ecosystems, proper management and supporting institutions. However, the interaction between these factors and ecosystem services is poorly understood. Therefore, we assessed how ecosystem services are represented in policy measures, recognized by local population and affected by weather extremes. We studied the Hungarian and Romanian parts of the flood-exposed Tisza River Basin, where all these factors are relevant for regional land and water management. Our qualitative assessment shows that, although the two regions share similar environmental conditions, the different social and institutional settings of the two countries cause a divergence in ecosystem services. Locally produced provisioning services are better recognized in Romania, while regulating (particularly water-regulation) and cultural services are better recognized in Hungary. Food supply is most affected by climate-related weather extremes and most strongly controlled by policy measures in both countries. However, especially in Romania, policy measures support medicinal and genetic resources, and some regulating (e.g. pest regulation) and cultural services, only weakly or indirectly. We conclude that the analysis of ecosystem services in relation to climate-related weather extremes, policy measures and people’s recognition can contribute to a better management of the Tisza River Basin. We suggest that a better incorporation of ecosystem services in policy and management strategies could enhance and diversify the ecosystem service supply. A further quantification of ecosystem services can, therefore, provide a base for targeted and integrated planning and improved regional policy making.

Turning points in climate change adaptation

Concerned decision makers increasingly pose questions as to whether current management practices are able to cope with climate change and increased climate variability. This signifies a shift in the framing of climate change from asking what its potential impacts are to asking whether it induces policy failure and unacceptable change. In this paper, we explore the background, feasibility, and consequences of this new framing. We focus on the specific situation in which a social-political threshold of concern is likely to be exceeded as a result of climate change, requiring consideration of alternative strategies. Action is imperative when such a situation is conceivable, and at this point climate change becomes particularly relevant to decision makers. We call this situation an “adaptation turning point.” The assessment of adaptation turning points converts uncertainty surrounding the extent of a climate impact into a time range over which it is likely that specific thresholds will be exceeded. This can then be used to take adaptive action. Despite the difficulty in identifying adaptation turning points and the relative newness of the approach, experience so far suggests that the assessment generates a meaningful dialogue between stakeholders and scientists. Discussion revolves around the amount of change that is acceptable; how likely it is that unacceptable, or more favorable, conditions will be reached; and the adaptation pathways that need to be considered under these circumstances. Defining and renegotiating policy objectives under climate change are important topics in the governance of adaptation.

The future of the Rhine: stranded ships and no more salmon?

Climate studies show high likelihood of changing hydrological regimes in European rivers. Concerned authorities increasingly question the sustainability of current river management strategies. The aim of this paper is to apply the adaptation turning point (ATP) approach and demonstrates its potential for analysing turning points in river management strategies as a method to support authorities in decisions on adaptation to climate change. Two management strategies in the Rhine River basin were selected as case studies: (1) reintroduction of a sustainable population of Atlantic salmon and (2) inland shipping in relation to water depth variability. By applying the turning point approach, we search for answers to the following questions: when will these management strategies fail due to climate change impacts on the river’s hydrology? What adaptation measures exist to delay or avoid failure? The identification of adaption turning points is not easy, due to large scenario and model uncertainties in transient future projections of low-flow discharges and water temperatures. But the case studies demonstrate that the ATP approach is salient from a decision-maker’s perspective, because it addresses the timing of possible failure of current management strategies. Analysis of results allows policy makers to assess risks and the urgency for action and provides them with a time horizon for adaptation planning. It is also a valuable first step in the application of methods of formal appraisal of adaptation options when flexibility in planning is required.

Method selection in adaptation research : the case of the Delta Programme for the Dutch Wadden region

Many methods are available to support adaptation planning. Yet there is little guidance on their selection. A recently developed diagnostic framework offers a structured set of criteria to choose research methods for specific adaptation questions. It has been derived from science-driven cases mostly. This paper offers the first application to a policy-driven case. Thus, it aims to (1) assess the descriptive quality of the framework for adaptation planning and (2) reflect on its value in supporting method selection. The paper focuses on the research commissioned for adaptation policymaking by the Dutch Delta Programme in the Wadden region. It compares the research methods used in the Delta Programme with those suggested by the diagnostic framework. It concludes that the selection of methods in the adaptation planning process can be described quite well by the decision trees of the diagnostic framework. Deviations occurred mostly for pragmatic reasons when the selection is informed by practical limitations of the policymaking process, such as available resources, time constraints and experience of the involved experts. It is recommended to enrich the diagnostic framework with methods from adaptation practice and consult it in climate adaptation studies at an early stage.

Sectorial Water Use Trends in the Urbanizing Pearl River Delta, China

Assessing and managing water use is crucial for supporting sustainable river basin management and regional development. The first consistent and comprehensive assessment of sectorial water use in the Pearl River Delta (PRD) is presented by analysing homogenized annual water use data from 2000 to 2010 in relation to socio economic statistics for the same period. An abstraction of water use, using the concept of water use intensity, and based on equations inspired by those used in global water resource models, is developed to explore the driving forces underlying water use changes in domestic, industrial and agricultural sectors. We do this at both the level of the region as a whole, as well as for the nine cities that constitute the PRD separately. We find that, despite strong population and economic growth, the PRD managed to stabilize its absolute water use by significant improvements in industrial water use intensities, and early stabilisation of domestic water use intensities. Results reveal large internal differentiation of sectorial water use among the cities in this region, with industrial water use intensity varying from -80 to +95% and domestic water use intensity by +/- 30% compared to the PRD average. In general, per capita water use is highest in the cities that industrialised first. Yet, all cities except Guangzhou are expected to approach a saturation value of per capita water use much below what is suggested in recent global studies. Therefore, existing global assessments probably have overestimated future domestic water use in developing countries. Although scarce and uncertain input data and model limitations lead to a high level of uncertainty, the presented conceptualization of water use is useful in exploring the underlying driving forces of water use trends.

Many-objective robust decision making for water allocation under climate change

Water allocation is facing profound challenges due to climate change uncertainties. To identify adaptive water allocation strategies that are robust to climate change uncertainties, a model framework combining many-objective robust decision making and biophysical modeling is developed for large rivers. The framework was applied to the Pearl River basin (PRB), China where sufficient flow to the delta is required to reduce saltwater intrusion in the dry season. Before identifying and assessing robust water allocation plans for the future, the performance of ten state-of-the-art MOEAs (multi-objective evolutionary algorithms) is evaluated for the water allocation problem in the PRB. The Borg multi-objective evolutionary algorithm (Borg MOEA), which is a self-adaptive optimization algorithm, has the best performance during the historical periods. Therefore it is selected to generate new water allocation plans for the future (2079-2099). This study shows that robust decision making using carefully selected MOEAs can help limit saltwater intrusion in the Pearl River Delta. However, the framework could perform poorly due to larger than expected climate change impacts on water availability. Results also show that subjective design choices from the researchers and/or water managers could potentially affect the ability of the model framework, and cause the most robust water allocation plans to fail under future climate change. Developing robust allocation plans in a river basin suffering from increasing water shortage requires the researchers and water managers to well characterize future climate change of the study regions and vulnerabilities of their tools.