Importance of snow and glacier meltwater for agriculture on the Indo-Gangetic Plain
Biemans, H. ; Siderius, C. ; Lutz, A.F. ; Nepal, S. ; Ahmad, B. ; Hassan, T. ; Bloh, W. von; Wijngaard, R.R. ; Wester, P. ; Shrestha, A.B. ; Immerzeel, W.W. - \ 2019
Nature Sustainability 2 (2019)7. - ISSN 2398-9629 - p. 594 - 601.
Densely populated floodplains downstream of Asia’s mountain ranges depend heavily on mountain water resources, in particular for irrigation. An intensive and complex multi-cropping irrigated agricultural system has developed here to optimize the use of these mountain water resources in conjunction with monsoonal rainfall. Snow and glacier melt thereby modulate the seasonal pattern of river flows and, together with groundwater, provide water when rainfall is scarce. Climate change is expected to weaken this modulating effect, with potentially strong effects on food production in one of the world’s breadbaskets. Here we quantify the space-, time- and crop-specific dependence of agriculture in the Indo-Gangetic Plains on mountain water resources, using a coupled state-of-the-art, high-resolution, cryosphere–hydrology–crop model. We show that dependence varies strongly in space and time and is highest in the Indus basin, where in the pre-monsoon season up to 60% of the total irrigation withdrawals originate from mountain snow and glacier melt, and that it contributes an additional 11% to total crop production. Although dependence in the floodplains of the Ganges is comparatively lower, meltwater is still essential during the dry season, in particular for crops such as sugar cane. The dependency on meltwater in the Brahmaputra is negligible. In total, 129 million farmers in the Indus and Ganges substantially depend on snow and glacier melt for their livelihoods. Snow and glacier melt provides enough water to grow food crops to sustain a balanced diet for 38 million people. These findings provide important information for agricultural and climate change adaptation policies in a climate change hot spot where shifts in water availability and demand are projected as a result of climate change and socio-economic growth.
The need for bottom-up assessments of climate risks and adaptation in climate-sensitive regions
Conway, Declan ; Nicholls, Robert J. ; Brown, Sally ; Tebboth, Mark G.L. ; Adger, William Neil ; Ahmad, Bashir ; Biemans, Hester ; Crick, Florence ; Lutz, Arthur F. ; Campos, Ricardo Safra De; Said, Mohammed ; Singh, Chandni ; Zaroug, Modathir Abdalla Hassan ; Ludi, Eva ; New, Mark ; Wester, Philippus - \ 2019
Nature Climate Change 9 (2019)7. - ISSN 1758-678X - p. 503 - 511.
Studies of climate change at specific intervals of future warming have primarily been addressed through top-down approaches using climate projections and modelled impacts. In contrast, bottom-up approaches focus on the recent past and present vulnerability. Here, we examine climate signals at different increments of warming and consider the need to reconcile top-down and bottom-up approaches. We synthesise insights from recent studies in three climate-sensitive systems where change is a defining feature of the human-environment system. Whilst top-down and bottom-up approaches generate complementary insights into who and what is at risk, integrating their results is a much-needed step towards developing relevant information to address the needs of immediate adaptation decisions.
South Asian river basins in a 1.5 °C warmer world
Lutz, Arthur F. ; Maat, Herbert W. ter; Wijngaard, René R. ; Biemans, Hester ; Syed, Abu ; Shrestha, Arun B. ; Wester, Philippus ; Immerzeel, Walter W. - \ 2019
Regional Environmental Change 19 (2019)3. - ISSN 1436-3798 - p. 833 - 847.
1.5 degrees - Brahmaputra - Climate change - Ganges - Indus - Paris agreement - South Asia
In 2015, with the signing of the “Paris Agreement”, 195 countries committed to limiting the increase in global temperature to less than 2 °C with respect to pre-industrial levels and to aim at limiting the increase to 1.5 °C by 2100. The regional ramifications of those thresholds remain however largely unknown and variability in the magnitude of change and the associated impacts are yet to be quantified. We provide a regional quantitative assessment of the impacts of a 1.5 versus a 2 °C global warming for a major global climate change hotspot: the Indus, Ganges, and Brahmaputra river basins (IGB) in South Asia, by analyzing changes in climate change indicators based on 1.5 and 2 °C global warming scenarios. In the analyzed ensemble of general circulation models, a global temperature increase of 1.5 °C implies a temperature increase of 1.4–2.6 (μ = 2.1) °C for the IGB. For the 2.0 °C scenario, the increase would be 2.0–3.4 (μ = 2.7) °C. We show that climate change impacts are more adverse under 2 °C versus 1.5 °C warming and that changes in the indicators’ values are in general linearly correlated to average temperature increase. We also show that for climate projections following Representative Concentration Pathways 4.5 and 8.5, which may be more realistic, the regional temperature increases and changes in climate change indicators are much stronger than for the 1.5 and 2 °C scenarios.
Climate change vs. socio-economic development : Understanding the future South Asian water gap
Wijngaard, René Reijer ; Biemans, Hester ; Friedrich Lutz, Arthur ; Bhakta Shrestha, Arun ; Wester, Philippus ; Willem Immerzeel, Walter - \ 2018
Hydrology and Earth System Sciences 22 (2018)12. - ISSN 1027-5606 - p. 6297 - 6321.
The Indus, Ganges, and Brahmaputra (IGB) river basins provide about 900 million people with water resources used for agricultural, domestic, and industrial purposes. These river basins are marked as "climate change hotspots", where climate change is expected to affect monsoon dynamics and the amount of meltwater from snow and ice, and thus the amount of water available. Simultaneously, rapid and continuous population growth as well as strong economic development will likely result in a rapid increase in water demand. Since quantification of these future trends is missing, it is rather uncertain how the future South Asian water gap will develop. To this end, we assess the combined impacts of climate change and socio-economic development on the future "blue" water gap in the IGB until the end of the 21st century. We apply a coupled modelling approach consisting of the distributed cryospheric-hydrological model SPHY, which simulates current and future upstream water supply, and the hydrology and crop production model LPJmL, which simulates current and future downstream water supply and demand. We force the coupled models with an ensemble of eight representative downscaled general circulation models (GCMs) that are selected from the RCP4.5 and RCP8.5 scenarios, and a set of land use and socio-economic scenarios that are consistent with the shared socio-economic pathway (SSP) marker scenarios 1 and 3. The simulation outputs are used to analyse changes in the water availability, supply, demand, and gap. The outcomes show an increase in surface water availability towards the end of the 21st century, which can mainly be attributed to increases in monsoon precipitation. However, despite the increase in surface water availability, the strong socio-economic development and associated increase in water demand will likely lead to an increase in the water gap during the 21st century. This indicates that socio-economic development is the key driver in the evolution of the future South Asian water gap. The transgression of future environmental flows will likely be limited, with sustained environmental flow requirements during the monsoon season and unmet environmental flow requirements during the low-flow season in the Indus and Ganges river basins.
Turning the tide? : The role of participation and learning in strengthening Tidal River Management in the Bangladesh Delta
Mutahara, Mahmuda - \ 2018
Wageningen University. Promotor(en): A.E.J. Wals, co-promotor(en): J.F. Warner; P. Wester. - Wageningen : Wageningen University - ISBN 9789463432375 - 220
This thesis analyses the role of participation and learning in enabling more sustainable land and water management processes in the southwest coastal delta of Bangladesh. A large portion of this coastal delta is frequently flooded, in part due to the waterlogging and drainage congestion caused by large-scale structural engineering (e.g. the creation of embankments and polders). To relieve drainage congestion and restore rivers and conserve tidal nature in this area, the Tidal River Management (TRM) approach has become the formally accepted strategy of Bangladesh’s public-sector water management. Local communities had earlier established the TRM process, which has its roots in indigenous knowledge, without the support of government authorities, but in 2001 it was approved formally as a novel re-interpretation of the polder concept. This thesis aims to explore whether this new shift in emphasis towards a centring of learning and participation for developing stakeholders’ capacity to flood risk reduction in Bangladesh delta. It focusses on innovative ‘delta triangular’ (Δ) relationships using a socio-eco-technical systems approach, social learning orientation, conflict and co-operation dynamics and multi-stakeholder process for exploring TRM as a modality of adaptive delta management.
The people of the southwest part of Bangladesh delta have adapted to the forces of nature (storm surges-salinity-flooding) for generations. They have traditional wisdom and some practical knowledge to face the hazards. It would stand to reason that the community people have the right to take part in the delta management system in this area. However, effective participation and sustainable stakeholder co-ordination is still challenging in the existing management approach which is theoretically introduced as multi-stakeholder process, but is not functional in practice.
Within this thesis, the General Introduction (Chapter 1) is concerned with defining the aim of the overall thesis as it intends to contribute to an understanding of how learning and change processes have developed (or, as the case may be, failed to develop) in adapting a delta management system and how multi-stakeholder approaches are utilized. The overall strategy includes documentary research, local surveys, multi-stakeholder focus groups both with subgroups and all aforementioned communities to enable social learning, dialogue and co-ordination. A historical analysis is made of the origins of TRM and the continuing struggles local stakeholders face with government agencies concerning this innovation.
Chapter 2 explores the transitions of delta management in Bangladesh, following the history of the waterlogging hazard in the Southwest and strategies to deal with it. Transformation of the dynamic delta system is also outlined here under a multi-dimensional socio-eco-technical approach that shows bio-physical restoration, socio-economic transformation and socio-institutional adaptation due to TRM implementation in the southwest delta in Bangladesh. Evolution and formalization of Tidal River Management (TRM) has restored the river’s capacity, reduced waterlogging and improved agricultural land in the study area. The developed land reforms made tremendous changes in the production system, introducing large-scale agro-fisheries mixed cultivation in most of the beel (depression) areas. Due to the intensive shrimp aquacultures in saline water, severe environmental degradation and ecological imbalance occurred in this sensitive area. This chapter also discusses community institutionalization, change in conflict and complexities within adaptive delta management.
To improve the understanding of Tidal River Management in the Southwest delta in Bangladesh, Chapter 3 analyzes four cases of TRM from a social learning perspective. Formal and informal TRM cases were investigated following an integrated participatory evaluation based on individual and organizational learning outputs regarding the adaptation of TRM. Individuals and groups of community stakeholders have gained and shared knowledge through their experiences and efforts. Although government agencies and other involved organizations leave some space for experimenting and monitoring, they rarely practice knowledge sharing and exchange with others due to their entanglement in a complex bureaucratic system. Social learning processes in most cases of TRM that seem to dominate, represent individual and single-loop learning, that is, learning to improve existing practices. Only a few instances of double-loop learning were found. Hence, a rethinking of assumptions and strategies to change the process was rare. It was found hard to ascertain double or triple-loop learning particularly, because of stakeholders’ fixation on pre-determined TRM goals, leaving little room for deeper reflection.
Chapter 4 analyses the conflicts and cooperation in a local (and regional) delta management system with planning and practicing Tidal River Management (TRM) by applying a modified Transboundary Water Interaction Nexus model which provides a clearer understanding of the conflict and co-operation dynamic in local water governance. Applying the model, revealed that the recently the conflict continuum has become more “powerized” and “violized” than before while co-operation has declined significantly. This research indeed found conflict and cooperation to coexist, with a predominance of conflict, and recommends incorporation of multiple-scales of analysis of conflict and cooperation (i.e. political, local/regional and policy scale) in this complex delta management system.
Since Chapter 3 showed that social learning only took place sporadically in formal and informal TRM cases, Chapter 5 looked at the presence of social learning in stakeholder participation in management transitions and at the levers and obstacles that emerge. Using a participatory evaluation methodology, problems and prospects of effective stakeholder participation in the delta management focusing on Tidal River Management in Bangladesh were investigated. The result shows that multi-stakeholder partnerships have rarely functioned in government-implemented delta management projects. In regional water governance, trust and commitment is even declining in the social network due to a gap in learning integration. It appears that a generative learning partnership needs to exist both horizontally and vertically, and needs to be more equitable to enable more effective participation, successful social learning and, ultimately, sustainable delta management.
Chapter 6 delineates and integrates main findings, reflections and recommendations. The thesis, as a multi-purposive learning process, led to a clearer understanding of the complexities of implementing and supporting multi-stakeholder networks and communities, and of creating societal impact in the context of TRM adaptation. The challenges in this delta management are connected as much to or even more to institutional, social and political aspects than to the physical domains. The final chapters of the thesis focus on some of the cross-cutting issues that are emerging and on some of the difficulties encountered during the research. The major restrictions this research reveals are the gaps in actions and interactions between communities, authorities and other development agencies, but also the limitations of learning between individuals’ and organizations. This chapter recommends to integrate social learning in multi-stakeholder partnerships within the delta management system as a way to facilitate multi-actor participation and to improve the effectiveness of delta water management practices.
Social learning for adaptive delta management : Tidal River Management in the Bangladesh Delta
Mutahara, Muhmuda ; Warner, Jeroen F. ; Wals, Arjen E.J. ; Shah Alam Khan, M. ; Wester, Flip - \ 2018
International Journal of Water Resources Development 34 (2018)6. - ISSN 0790-0627 - p. 923 - 943.
adaptive delta management - Bangladesh - participation - social learning - Tidal River Management
The article analyzes Tidal River Management in Bangladesh from a social learning perspective. Four cases were investigated using participatory assessment. Knowledge acquisition through transformations in the Tidal River Management process was explored as an intended learning outcome. The study finds that social learning occurred more prominently at the individual stakeholder level and less at the collective level. For Tidal River Management to be responsive and sustainable, especially in times of increased uncertainty and climate vulnerability, more attention needs to be paid to coordination and facilitation of multi-level learning that includes all stakeholders.
Commercial farmers’ strategies to control water resources in South Africa : an empirical view of reform
Méndez-Barrientos, Linda Estelí ; Kemerink, Jeltsje Sanne ; Wester, Flip ; Molle, François - \ 2018
International Journal of Water Resources Development 34 (2018)2. - ISSN 0790-0627 - p. 245 - 258.
Commercial farmers - irrigation boards - South Africa - water reform - water resources - water rights - water user association
This article shows how large-scale commercial farmers, individually and collectively, are responding to land and water reform processes in the Thukela River basin, KwaZulu-Natal, South Africa. With a high degree of innovative agency, commercial farmers have effectively executed four strategies, enabling them to adapt and use their access to resources to neutralize multiple water reform efforts that once promised to be catalysts for inclusive change in the post-apartheid era. It is likely that policy alone will not facilitate the envisioned transformation, if local practices are not sufficiently understood and anticipated by the governmental officials charged with the implementation of water reform processes.
Bringing in the floods : a comparative study on controlled flooding in the Dutch, Bangladesh and Vietnamese deltas
Staveren, Martijn F. van - \ 2017
Wageningen University. Promotor(en): J.P.M. Tatenhove, co-promotor(en): J.F. Warner; P. Wester. - Wageningen : Wageningen University - ISBN 9789463437035 - 174
water management - flooding - deltas - hydraulic engineering - rivers - environmental management - environmental policy - environmental control - netherlands - vietnam - bangladesh - waterbeheer - inundatie - delta's - waterbouwkunde - rivieren - milieubeheer - milieubeleid - milieubeheersing - nederland - vietnam - bangladesh
This thesis investigates contested initiatives to restore controlled flooding in the deltas of the Dutch, Bangladesh and Vietnamese (Mekong) deltas. Restoring controlled flooding is a seemingly contradictory measure in densely populated delta areas, where approaches based on full flood prevention has been typically dominant for decades. This has instigated the question how the emergence of restored controlled flooding initiatives can be explained. Related, this study reflects on how controlled flooding could contribute to long-term flood risk management and sustainable development in deltas, which are simultaneously attractive and vulnerable places for humans to live in. In order to answer this question, a case study approach has been used to investigate social, environmental and technological factors that have shaped controlled flooding initiatives. Cases have been identified that materialized under different conditions: from very dynamic delta environments to relatively stable ones, and from interventions driven by “top-down” policies to “bottom-up” action to modify or remove embankments. This thesis has an article-based structure, which means that individual chapters (2-5) have been designed for publication with peer reviewed academic journals. Chapter 1 provides the general background information, problem definition, and objectives. Chapter 6 ties together the findings of the individual case study chapters and presents the conclusions.
Chapter 2 conceptualizes deltas as interacting social-ecological-technological systems. It argues that a better understanding of how hydraulic infrastructure influences social processes and environmental dynamics in deltas is critical to understand how deltas evolve over time. By means of the delta trajectories concept, the chapter presents a way to understand this interaction. It also presents a way to understand the sustainability of a delta trajectory, and discusses how new flood management concepts might contribute to “realigning” the development trajectory towards more sustainable system states.
In Chapter 3, the first controlled flooding case is investigated. The Noordwaard is an agricultural polder, located at the junction of tides and riverine discharge in the Netherlands. As part of the Room for the River programme, the northern embankments were lowered which enables the inflow of water during high water levels in the river Merwede. This reduces peak water levels in the river, supports the adjacent freshwater Biesbosch wetland by means of restored water dynamics, but also affects the possibilities for agricultural production. The chapter highlights that a strong coupling can be observed between the domains of water safety and nature development objectives, and that a top-down decision concluded a long stakeholder negotiation processes. From the perspective of “subsiding polder lands,” controlled flooding is not regarded for its strategic importance, as excessive sedimentation would hamper the intended design discharge of the area.
Chapter 4 explores the Tidal River Management concept. In the coastal zone of Bangladesh, community-enforced embankment breaches have opened up some of the polders or low-lying areas called “beels,” and exposed them to tidal influence again. Besides stimulating agricultural production and providing safer places to live in, the extensive network of polder embankments also caused increased sedimentation in the region’s rivers, and water logging in enclosed areas due to insufficient drainage possibilities. The chapter highlights that policy debates in Bangladesh have revolved around adopting “open” or “closed” approaches, where TRM represents a hybrid form. The case showed that TRM involves water management and sediment management, and that it represented a “social opening up” for local communities and NGOs to get involved with water projects and embankment removal.
Plans to restore seasonal flooding in the Mekong delta are center stage in Chapter 5. The Mekong delta system is very dynamic and dealing with the delta’s water resources, in connection with intensive rice production, have been heavily debated by Vietnamese and international policy makers. This chapter investigates a number of older and more recent long-term development plans for the Mekong delta. This analysis highlights how ideas about controlled flooding and flood control have gradually evolved over time. The most recent delta management plan suggests to restore seasonal flooding in some parts of the delta, as a way to safeguard downstream urban areas from peak flows, and as a way to improve the conditions for agricultural production.
Chapter 6 summarizes the findings of the case study chapters one by one, and concisely answers the research questions. It highlights key similarities and differences when it comes to social, environmental and technological dimensions, and discusses these findings with the literature on flood risk management policy, complex adaptive systems research, and delta studies. The findings demonstrate that environmental dynamics have been critical to emphasize the potential of restoring controlled flooding, but that social and technological factors have been important enablers or constrainers for controlled flooding initiatives to take shape. In itself, controlled flooding reconciles ecosystem-based ideas about flood management with more mainstream policies based on flood control. For this reason controlled flooding can be seen as a “niche-development” with limited influence on how flood management policies, and environmental delta systems, evolve. At the same time, controlled flooding has been acknowledged for its strategic opportunities, for example when it comes to diverting peak water discharges, land heightening by means of capturing suspended sediment, and by providing nutrient for agricultural. This offers opportunities for further thinking about and conceptual development of controlled flooding.
Climate adaptation approaches and key policy characteristics : Cases from South Asia
Vij, Sumit ; Moors, Eddy ; Ahmad, Bashir ; Uzzaman, Arfan ; Bhadwal, Suruchi ; Biesbroek, Robbert ; Gioli, Giovanna ; Groot, Annemarie ; Mallick, Dwijen ; Regmi, Bimal ; Saeed, Basharat Ahmed ; Ishaq, Sultan ; Thapa, Bhuwan ; Werners, Saskia E. ; Wester, Philippus - \ 2017
Environmental Science & Policy 78 (2017). - ISSN 1462-9011 - p. 58 - 65.
Adaptation - Climate change - Long-term - Policy approaches - South Asia
This paper analyses and assesses how existing policies and approaches in South Asia consider long-term climate change adaptation. Presently, it is unclear what approaches are used in the existing policies to cope with the future climatic changes. Our research framework consists of two components. First, we identify and define key characteristics of adaptation policy approaches based on a review of scientific journal articles. The key characteristics identified are institutional flexibility, adaptive nature, scalability and reflexivity. Second, we analyse the presence of these characteristics in the climate change adaptation policies of Bangladesh, India, Nepal, and Pakistan. Our findings show that the four South Asian countries contribute to only 8% of the total journal articles on adaptation policy, with least papers representing Pakistan and Nepal. Reviewing the adaptation policies, we find that except for the Climate Change Policy of Nepal, none of the policies discusses transboundary scale adaptation approaches. The identified adaptation policies lack focus on shared transboundary resources between the countries, and instead focus at national or sub-national scale. This is reflected by relatively low scores for the scalability characteristic. All the countries show high scores for institutional flexibility, suggesting that changing roles and responsibilities between government agencies for adaptation planning and implementation is accepted in the four countries. We conclude that to prevent a loss of flexibility and to promote scalability of shared transboundary resources, policy approaches such as anticipatory governance, robust decision-making, and adaptation pathways can be useful for long-term climate change adaptation.
Regulating groundwater use : The challenges of policy implementation in Guanajuato, Central Mexico
Hoogesteger van Dijk, Jaime ; Wester, Flip - \ 2017
Environmental Science & Policy 77 (2017). - ISSN 1462-9011 - p. 107 - 113.
Energy pricing - Groundwater management - Mexico - User self-regulation - Water markets - Water policy
Around the world it has proven very difficult to develop policies and interventions that ensure socio-environmentally sustainable groundwater use and exploitation. In the state of Guanajuato, Central Mexico, both the national government and the decentralized state government have pursued to regulate groundwater use through direct state control, groundwater markets, energy pricing, and user self-regulation. We present and analyze these regulatory mechanisms and their outcomes in the field. We argue that the close interdependencies of these regulatory mechanisms have pre-empted the effectiveness of these policy instruments as well as that of other measures aimed at reducing groundwater use in order to advance towards sustainable exploitation levels.
Governing the water user : experiences from Mexico
Rap, Edwin ; Wester, Flip - \ 2017
Journal of Environmental Policy and Planning 19 (2017)3. - ISSN 1523-908X - p. 293 - 307.
governmental technologies - Governmentality - Mexico - NRM - policy - power and knowledge - water governance
This article traces a policy shift that makes the ‘water user’ the main subject of water governance. From a Foucauldian perspective on governmentality these new subjectivities accompany neo-liberal governmental technologies to devolve autonomy from state institutions to an active user base, whilst retaining some ‘control at a distance’. The expectation is that individual subjects will incorporate control mechanisms and internalize norms and that this leads to new publicly auditable forms of self-regulation. The article questions the underlying assumption that policy necessarily accomplishes its strategic effects through governmentality. For this purpose, it draws on an ethnographic case study of how policy produced a new power/knowledge regime and how different societal actors and ‘user’ groups responded to that. The study specifically investigates the Mexican policy of irrigation management transfer during the 1990s, by which government transferred the public control over irrigation districts to locally organized water users’ associations (WUAs). The article argues that governmental technologies make and govern the ‘water user’ by discursively and materially constituting an organizational arrangement for user management (WUA), more than by directly acting on individuals’ self-regulated conduct. The analysis contributes to a broader reflection on the role of power/knowledge in natural resources management and decentralized resources governance.
Towards characterizing the adaptive capacity of farmer-managed irrigation systems : learnings from Nepal
Thapa, Bhuwan ; Scott, Christopher ; Wester, Flip ; Varady, Robert - \ 2016
Current Opinion in Environmental Sustainability 21 (2016). - ISSN 1877-3435 - p. 37 - 44.
Small-scale irrigation systems managed by farmers are facing multiple challenges including competing water demand, climatic variability and change, and socioeconomic transformation. Though the relevant institutions for irrigation management have developed coping and adaptation mechanisms, the intensity and frequency of the changes have weakened their institutional adaptive capacity. Using case examples mostly from Nepal, this paper studies the interconnections between seven key dimensions of adaptive capacity: the five capitals (human, financial, natural, social, and physical), governance, and learning. Long-term adaptation requires harnessing the synergies and tradeoffs between generic adaptive capacity that fosters broader development goals and specific adaptive capacity that strengthens climate-risk management. Measuring and addressing the interrelations among the seven adaptive-capacity dimensions aids in strengthening the long term sustainability of farmer-managed irrigation systems.
Selecting representative climate models for climate change impact studies: an advanced envelope-based selection approach : Advanced envelope-based climate model selection approach
Lutz, Arthur F. ; Maat, Herbert W. ter; Biemans, Hester ; Shrestha, Arun B. ; Wester, Philippus ; Immerzeel, Walter W. - \ 2016
International Journal of Climatology 36 (2016)12. - ISSN 0899-8418 - p. 3988 - 4005.
Climate change impact studies depend on projections of future climate provided by climate models. The number of climate models is large and increasing, yet limitations in computational capacity make it necessary to compromise the number of climate models that can be included in a climate change impact study. The selection of climate models is not straightforward and can be done by following different methods. Usually, the selection is either based on the entire range of changes in climatic variables as projected by the total ensemble of available climate models or on the skill of climate models to simulate past climate. The present study combines these approaches in a three-step sequential climate model selection procedure: (1) initial selection of climate models based on the range of projected changes in climatic means, (2) refined selection based on the range of projected changes in climatic extremes and (3) final selection based on the climate model skill to simulate past climate. This procedure is illustrated for a study area covering the Indus, Ganges and Brahmaputra river basins. Subsequently, the changes in climate between 1971–2000 and 2071–2100 are analysed, showing that the future climate projections in this area are highly uncertain but that changes are imminent.
Hydrosocial territories: a political ecology perspective
Boelens, Rutgerd ; Hoogesteger, Jaime ; Swyngedouw, Erik ; Vos, Jeroen ; Wester, Philippus - \ 2016
Water International 41 (2016)1. - ISSN 0250-8060 - p. 1 - 14.
governmentality - hydrosocial territories - political ecology - scalar politics - water governance
We define and explore hydrosocial territories as spatial configurations of people, institutions, water flows, hydraulic technology and the biophysical environment that revolve around the control of water. Territorial politics finds expression in encounters of diverse actors with divergent spatial and political-geographical interests. Their territory-building projections and strategies compete, superimpose and align to strengthen specific water-control claims. Thereby, actors continuously recompose the territory’s hydraulic grid, cultural reference frames, and political-economic relationships. Using a political ecology focus, we argue that territorial struggles go beyond battles over natural resources as they involve struggles over meaning, norms, knowledge, identity, authority and discourses.
Development of a sustainable livelihood security model for storm-surge hazard in the coastal areas of Bangladesh
Mutahara, Muhmuda ; Haque, Anisul ; Khan, M.S.A. ; Warner, Jeroen F. ; Wester, Flip - \ 2016
Stochastic environmental research and risk assessment 30 (2016)5. - ISSN 1436-3240 - p. 1301 - 1315.
Bangladesh - Coastal zone - Community - Hazard - Livelihood security - Multi- criteria analysis - Storm-surge
Coastal communities in Bangladesh are at great risk due to frequent cyclones and cyclone induced storm-surges, which damages inland and marine resource systems. In the present research, seven marginal livelihood groups including Farmers, Fisherman, Fry (shrimp) collectors, Salt farmers, Dry fishers, Forest resource extractors, and Daily wage labourers are identified to be extremely affected by storm- surges in the coastal area of Bangladesh. A livelihood security model was developed to investigate the security status of the coastal livelihood system in a participatory approach. In the model, livelihood security consists of five components: (1) Food, (2) Income, (3) Life & health, (4) House & properties, and (5) Water security. Analytical hierarchy process was followed to assess the livelihood security indicators based on respondents’ security options. The model was verified through direct field observation and expert judgment. The Livelihood Security Model yields a Livelihood Security Index which can be used for assessing and comparing the household security level (in %) of different livelihood groups in the storm-surge prone coastal areas. The model was applied with data from two major coastal areas (Cox’s Bazar and Satkhira) of Bangladesh and is applicable to other coastal areas having similar settings.
Risk assessment of chronic dietary exposure to the conjugated mycotoxin deoxynivalenol-3-β-glucoside in the Dutch population
Janssen, E.M. ; Sprong, R.C. ; Wester, P.W. ; Boevre, M. de; Mengelers, M.J.B. - \ 2015
World Mycotoxin Journal 8 (2015)5. - ISSN 1875-0710 - p. 561 - 572.
Deoxynivalenol - Exposure assessment - Grain - Masked mycotoxin - Modified mycotoxin
In this study, a risk assessment of dietary exposure to the conjugated mycotoxin deoxynivalenol-3-β-glucoside (DON-3G) in the Dutch population was conducted. Data on DON-3G levels in food products available in the Netherlands are scarce. Therefore, data on co-occurring levels of DON-3G and deoxynivalenol (DON), its parent compound, were used to estimate the DON-3G/DON ratio for several food product categories. This resulted in a DON-3G/DON ratio of 0.2(90% confidence interval (CI):0.04-0.9) in grains & grain-milling products, 0.3 (90% CI: 0.03-2.8) in grain-based products and 0.8 (90% CI: 0.4-1.8) in beer. These ratios were applied to the Dutch monitoring data of DON to estimate the DON-3G concentrations in food products available in the Netherlands. DON and DON-3G concentrations were combined with food consumption data of two Dutch National Food Consumption Surveys to assess chronic exposure in young children (2-6 years), children (7-16 years) and adults (17-69 years) using the Monte Carlo Risk Assessment program. The chronic exposure levels of DON, DON-3G and the sum of both compounds (DON+DON-3G) were compared to the tolerable daily intake (TDI) of 1 μg/kg body weight/day which is based on the most critical effect of DON, namely decreased body weight gain. The assumption was made that DON-3G is deconjugated and then fully absorbed as DON in the gastro-intestinal tract. Exposure (P97.5) of the population aged 7-16 years and 17-69 years to DON or DON-3G separately, did not exceed the TDI. However, exposure to upper bound levels of DON+DON-3G (i.e. worst-case scenario) in the same age categories (P97.5) exceeded the TDI with a maximum factor of 1.3. Exposure (P97.5) of the 2-6 year-olds to DON was close to the TDI. Within this group, exposure (P97.5) to upper bound levels of DON+DON-3G exceeded the TDI with not more than a factor 2.
The role of extreme events in reaching adaptation tipping points : A case study of flood risk management in Dhaka, Bangladesh
Ahmed, Farhana ; Gersonius, Berry ; Veerbeek, William ; Shah Alam Khan, M. ; Wester, Flip - \ 2015
Journal of Water and Climate Change 6 (2015)4. - ISSN 2040-2244 - p. 729 - 742.
Adaptation tipping point - Flood - Flood management - Flood risk - Urban growth
Adaptation tipping points (ATPs) refer to the situation where a policy or management strategy is no longer sufficient, and adjustments or alternative policies/strategies have to be considered. In developed countries, the main focus of research has been on characterising the occurrence of ATPs in the face of slow variables like climate change. In developing countries, the system characteristics that lead to ATPs are more uncertain and typically comprise a combination of drivers. It is well recognised that policies and management strategies have often shifted in the wake of extreme events like floods. By focusing on flood risk management (FRM), this paper explores the role of sudden or extreme events and other drivers that trigger ATPs. It analyses the historical flooding pattern of Dhaka and policies relevant to FRM, and determines the tipping points for policy-making. A timeline has been established between the flood events, co-drivers, policy interventions and institutional reforms over the last 50 years. ATPs in a developing country context have been found to result from hydrological factors and uncontrolled urban growth as well as foreign intervention, non-implementation or untimely implementation of planned measures and fund constraints.
Assessment of permafrost distribution maps in the Hindu Kush Himalayan region using rock glaciers mapped in Google Earth
Schmid, M.O. ; Baral, P. ; Gruber, S. ; Shahi, S. ; Shrestha, T. ; Stumm, D. ; Wester, P. - \ 2015
Cryosphere 9 (2015)6. - ISSN 1994-0416 - p. 2089 - 2099.
The extent and distribution of permafrost in the mountainous parts of the Hindu Kush Himalayan (HKH) region are largely unknown. A long tradition of permafrost research, predominantly on rather gentle relief, exists only on the Tibetan Plateau. Two permafrost maps are available digitally that cover the HKH and provide estimates of permafrost extent, i.e., the areal proportion of permafrost: the manually delineated Circum-Arctic Map of Permafrost and Ground Ice Conditions (Brown et al., 1998) and the Global Permafrost Zonation Index, based on a computer model (Gruber, 2012). This article provides a first-order assessment of these permafrost maps in the HKH region based on the mapping of rock glaciers. Rock glaciers were used as a proxy, because they are visual indicators of permafrost, can occur near the lowermost regional occurrence of permafrost in mountains, and can be delineated based on high-resolution remote sensing imagery freely available on Google Earth. For the mapping, 4000 square samples (∼ 30 km2) were randomly distributed over the HKH region. Every sample was investigated and rock glaciers were mapped by two independent researchers following precise mapping instructions. Samples with insufficient image quality were recorded but not mapped. We use the mapping of rock glaciers in Google Earth as first-order evidence for permafrost in mountain areas with severely limited ground truth. The minimum elevation of rock glaciers varies between 3500 and 5500 m a.s.l. within the region. The Circum-Arctic Map of Permafrost and Ground Ice Conditions does not reproduce mapped conditions in the HKH region adequately, whereas the Global Permafrost Zonation Index does so with more success. Based on this study, the Permafrost Zonation Index is inferred to be a reasonable first-order prediction of permafrost in the HKH. In the central part of the region a considerable deviation exists that needs further investigations.
Trends in flood risk management in deltas around the world: Are we going ‘soft’?
Wesselink, A. ; Warner, J.F. ; Syed, M.A. ; Chan, F. ; Tran, D.D. ; Huq, H. ; Huthoff, F. ; Thuy, N. Le; Pinter, N. ; Staveren, M.F. van; Wester, P. ; Zegwaard, A. - \ 2015
International Journal of Water Governance 3 (2015)4. - ISSN 2211-4491 - p. 25 - 46.
Flood-risk management (FRM) is shaped by context: a society’s cultural background; physical possibilities and constraints; and the historical development of that society’s economy, politi- cal system, education, etc. These provide different drivers for change, in interaction with more global developments. We compare historical and current FRM in six delta areas and their con- texts: Rhine/Meuse/Scheldt (The Netherlands), Pearl River (China), Mekong (Vietnam), Ganges/ Brahmaputra/Meghna (Bangladesh) Zambezi/Limpopo (Mozambique), and Mississippi (USA). We show that in many countries the emphasis is shifting from ‘hard’ engineering, such as dikes, towards non-structural ‘soft’ measures, such as planning restrictions or early warning systems, while the ‘hard’ responses are softened in some by a ‘building with nature’ approach. However, this is by no means a universal development. One consistent feature of the application of ‘hard’ FRM technology to deltas is that it pushes them towards a technological ‘lock-in’ in which fewer and fewer ‘soft’ FRM alternatives are feasible due to increased ood risks. By contrast, ‘soft’ FRM is typically exible, allowing a range of future options, including future hard elements if needed and appropriate. These experiences should lead to serious re ection on whether ‘hard’ FRM should be recommended when ‘soft’ FRM options are still open.
Intensive groundwater use and (in)equity: Processes and governance challenges
Hoogesteger van Dijk, J.D. ; Wester, P. - \ 2015
Environmental Science & Policy 51 (2015). - ISSN 1462-9011 - p. 117 - 124.
water - policies - india - sustainability - organizations - irrigation - strategies - management - highlands - depletion
Groundwater forms the basis for millions of rural and urban livelihoods around the world. Building on insights from the theory of access, in this article we present how groundwater development has brought much well-fare in many parts of the world; and how resulting intensive groundwater use is leading to ill-fare through aquifer overexploitation and processes of water accumulation and dispossession. We show the difficulty of state regulation and the modest achievements of other governance approaches that aim to solve existing groundwater problems. To study these processes we propose a framework of analysis that is based on the study of hydrosocial-networks, the political economy of groundwater and the domains and discourses that define groundwater access. Such analysis highlights the challenges of devising policies and modes of governance that contribute to social and environmental sustainability in intensively used aquifers. These we argue should build on an analysis of equity that scrutinizes the discourses, actors, powers and procedures that define groundwater access. By inciting debates on equity a first and fundamental step can be made toward advancing more inclusive groundwater governance that crucially engages the marginalized and addresses their groundwater problems, concerns and needs.