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901.
The South Saskatchewan River Basin (SSRB) of Alberta, Canada, is semiarid and under severe water stress due to increasing human demands. We present the first examination of projected changes in SSRB runoff from a large set of North American Regional Climate Change Assessment Program regional climate models (RCMs) plus one Coordinated Regional Climate Downscaling Experiment RCM. We used six different runoff estimation methods: total surface and subsurface runoff (total runoff), surface runoff, and four estimations based on Budyko functions. Most RCM estimations showed substantial biases and distribution differences when compared to observed data; thus bias correction was necessary. Total runoff was the best of the six variables in modeling observed runoff for each of the four SSRB subbasins. Projected total runoff for 2041–2070 shows a geographic gradient in the SSRB, with possible drying in the southern Oldman River subbasin and possible increased runoff in the northernmost Red Deer River subbasin. A shift to an earlier spring peak in runoff and drier late summer, with a need for increased irrigation, should be expected. In a first examination of the important question of projected changes in interannual variability, we show increasing magnitude. This result further adds to adaptation challenges over the course of this century in this basin, which is already largely closed to further allocation.  相似文献   
902.
It is increasingly expected that private actors play the role as entrepreneurs and front-runners in implementing climate measures, whereas empirical studies of the position, role and engagement of private actors are scarce. Situated in the context of urban planning, a critical arena for triggering climate transitions, the aim of this paper is to explore how Swedish property developers respond to climate change. Qualitative analyses of corporate policy documents and semi-structured interviews with property developers reveal a vast divergence between the written policies, where leadership ambitions are high, and how the practice of property development is discussed in interviews. In the latter, there is little evidence of property developers pursuing a forward-looking or cutting-edge climate change agenda. Instead, they are critical of increased public regulation for climate-oriented measures. Explanations both confirm previous studies, highlighting lack of perceived customer demand, uncertainty of financial returns and limited innovations, and add new elements of place-dependency suggesting that innovative and front-runner practices can only be realized in the larger urban areas. Municipalities seeking to improve their climate-oriented profile in urban planning by involving private property developers need to develop strategies to maneuver the variance in responses to increase the effectiveness of implementation.  相似文献   
903.
This paper introduces the terminology of (mal)adaptation opportunism – a situation in which projects undertaken in the name of climate change adaptation (CCA) are overrun by interests other than the stated or intended objectives of the CCA project. A goal of CCA projects is to reduce poverty and promote social justice. The case of the threat of displacement of the community of Kewunor by the Trasacco Estate Development Company (TEDC), after the construction of the Ada Sea Defense System (AdSDS) of Ghana as a CCA, is illustrative of this concept of (mal)adaptation opportunism. Through a narrative presentation of eight different accounts concerning this issue, I demonstrate how (mal)adaptation opportunism arises and is often motivated by economic interests. This case illustrates how economic interests can take over not only CCA projects but also their maladaptive effects.  相似文献   
904.
Urban areas worldwide are challenged by climate change and urban flooding. Within the academic literature, adaptive measures that can be integrated into other issues such as recreation, nature reserves, and social issues are considered the way forward. Adaptation has recently become a mandatory planning theme for Danish municipalities, which in the absence of established practices are struggling to find the best institutional set-up to address adaptation as an integrated issue. Based on a case study of an integrated project organised as a partnership, this article identifies and discusses governance challenges that must be addressed if municipalities are to benefit from synergies through integrated projects. The municipality in question has established a partnership with housing organisations, foundations, and a utility company as well as facilitated a dialogue with citizens and institutions to address flooding threats and social issues at the neighbourhood scale. Because of strong political and leadership support, funding from partners, and good project facilitation both partners and politicians are enthusiastic about the project and its potential. Several challenges, however, needed to be addressed, particularly in relation to clashing norms from different governance paradigms. This is an issue requiring more attention both in research and practice.  相似文献   
905.
Government agencies in cities across Asia recognise that municipalities must take steps to adapt to projected climate changes if people and places are to be kept above water. This paper focuses on planning for climate change in Bangkok because it ranks among the top 10 port cities vulnerable to climate change related flooding. It is also understood that the most devastating impacts of climate change will be suffered by the city's most vulnerable residents: the poor. Not only do impoverished people occupy physically vulnerable space, such as riverbanks, but they are also the least equipped to recover from the disruption of their livelihoods.

Several scholars have identified “institutional traps” that prevent the Thai government from successfully aiding poor and marginalised flood victims in the past. These include poor coordination, lack of monitoring and evaluation, rigidity, crisis management and elite capture. Lebel, Manuta, and Garden (2011, 56) Lebel, L., J.B. Manuta, and P. Garden. 2011. “Institutional Traps and Vulnerability to Changes in Climate and Flood Regimes in Thailand.” Regional Environmental Change 11 (1): 4558.[Crossref], [Web of Science ®] [Google Scholar] pose the crucial question: “How have individuals – from local community leaders through to national level politicians and bureaucrats – successfully influenced policy and programmes to avoid institutional traps and improve adaptive capacities to climate change?”

In this paper, we begin to address this question through examining emergent methods of “community based adaptation” and reviewing case studies of adaptation action from other vulnerable communities in the Global South. These lessons – such as overcoming institutional rigidity and avoiding elite capture – are important for Bangkok and other cities in the Global South that face many different challenges by global environmental change.  相似文献   
906.
The aim of this experiment was to determine the impacts of climate change on soil profile concentrations and diffusion effluxes of methane in a rice–wheat annual rotation ecosystem in Southeastern China. We initiated a field experiment with four treatments:ambient conditions(CKs), CO_2 concentration elevated to ~ 500 μmol/mol(FACE),temperature elevated by ca. 2°C(T) and combined elevation of CO_2 concentration and temperature(FACE + T). A multilevel sampling probe was designed to collect the soil gas at four different depths, namely, 7 cm, 15 cm, 30 cm and 50 cm. Methane concentrations were higher during the rice season and decreased with depth, while lower during the wheat season and increased with depth. Compared to CK, mean methane concentration was increased by 42%, 57% and 71% under the FACE, FACE + T and T treatments, respectively, at the 7 cm depth during the rice season(p 0.05). Mean methane diffusion effluxes to the 7 cm depth were positive in the rice season and negative in the wheat season, resulting in the paddy field being a source and weak sink, respectively. Moreover, mean methane diffusion effluxes in the rice season were 0.94, 1.19 and 1.42 mg C/(m~2·hr) in the FACE,FACE + T and T treatments, respectively, being clearly higher than that in the CK. The results indicated that elevated atmospheric CO_2 concentration and temperature could significantly increase soil profile methane concentrations and their effluxes from a rice–wheat field annual rotation ecosystem(p 0.05).  相似文献   
907.
In this study we present a novel research approach to obtaining behavior-based evidence of regional climate change attitudes, using the 2011 Fukushima nuclear plant incident as a natural experiment. Our approach allows us to produce the first non-survey-based empirical evidence of a trans-Atlantic divide in public opinion on the environment and climate change that investors assign to fossil-based and renewable energy. This value is based on the perceived potential of these fuel types to substitute for nuclear generation in the aftermath of the Fukushima crisis. We carry out an event study to examine differences in abnormal returns of global coal and renewable energy companies on European and American stock exchanges. We find that investors trading on U.S. markets exhibit a significantly more favorable perception of coal stock profitability, while investors trading on European exchanges display a more favorable perception about profitability of renewable energy stocks.  相似文献   
908.
This paper addresses methodological issues in estimating carbon (C) sequestration potential, baseline determination, additionality and leakage in Khammam district, Andhra Pradesh, southern part of India. Technical potential for afforestation on cultivable wastelands, fallow, and marginal croplands was considered for Eucalyptus clonal plantations. Field studies for aboveground and belowground biomass, woody litter, and soil organic carbon for baseline and project scenarios were conducted to estimate the carbon sequestration potential. The baseline carbon stock was estimated to be 45.3 t C/ha, predominately in soils. The additional carbon sequestration potential under the project scenario for 30 years is estimated to be 12.8 t C/ha/year inclusive of harvest regimes and carbon emissions due to biomass burning and fertilizer application. Considering carbon storage in harvested wood, an additional 45% carbon benefit can be accounted. The project scenario has a higher benefit/cost ratio compared to the baseline scenario. The initial investment cost requirement, however, is high and lack of access to investment is a significant barrier for adoption of agroforestry in the district.
N. H. RavindranathEmail:
  相似文献   
909.
Abstract: Unsustainable fishing simplifies food chains and, as with aquaculture, can result in reliance on a few economically valuable species. This lack of diversity may increase risks of ecological and economic disruptions. Centuries of intense fishing have extirpated most apex predators in the Gulf of Maine (United States and Canada), effectively creating an American lobster (Homarus americanus) monoculture. Over the past 20 years, the economic diversity of marine resources harvested in Maine has declined by almost 70%. Today, over 80% of the value of Maine's fish and seafood landings is from highly abundant lobsters. Inflation‐corrected income from lobsters in Maine has steadily increased by nearly 400% since 1985. Fisheries managers, policy makers, and fishers view this as a success. However, such lucrative monocultures increase the social and ecological consequences of future declines in lobsters. In southern New England, disease and stresses related to increases in ocean temperature resulted in more than a 70% decline in lobster abundance, prompting managers to propose closing that fishery. A similar collapse in Maine could fundamentally disrupt the social and economic foundation of its coast. We suggest the current success of Maine's lobster fishery is a gilded trap. Gilded traps are a type of social trap in which collective actions resulting from economically attractive opportunities outweigh concerns over associated social and ecological risks or consequences. Large financial gain creates a strong reinforcing feedback that deepens the trap. Avoiding or escaping gilded traps requires managing for increased biological and economic diversity. This is difficult to do prior to a crisis while financial incentives for maintaining the status quo are large. The long‐term challenge is to shift fisheries management away from single species toward integrated social‐ecological approaches that diversify local ecosystems, societies, and economies.  相似文献   
910.
In this article we develop a concept for the assessment of state’s susceptibility to drought based on a political science perspective. Different sources of capacities and sensitivities need to be taken into account to assess the overall susceptibility of states as political systems. We argue that the overall susceptibility of a society depends on an interplay of state capacity and readiness as main elements of political susceptibility, wealth and economic sensitivity as elements of economic susceptibility and the degree of social integration. To transform the conceptual model into a susceptibility assessment we developed an inference model in order to generate quantitative indices. For this purpose we apply fuzzy set theory using data from our case study regions, namely Andhra Pradesh (India), the Volga region (Russia) and (Southern) Portugal. The resulting computed trends for Portugal suggest that the society will be able to deal even with severe natural conditions due to existing political, economic, and social conditions. The assessment results for the Indian and Russian case study regions, in contrast, give reason for precaution since the occurrence of drought-induced crisis events seems much more likely in the light of more crucial, overall conditions, namely lower degrees of state capacity and readiness as well as, in the case of India, a high economic susceptibility. However, further improvements are possible given the improved availability of data and the integration of more qualitative information. Additionally, the expansion to further case study regions could help validate the overall concept.  相似文献   
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