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Ostrom proposed the underpinnings of a framework for the systematic study of the governance of complex social–ecological systems. Here we hypothesize that Ostrom's social–ecological system framework can be useful to build a classification system for small-scale benthic fisheries, regarding their governance processes and outcomes. The purpose of this paper is to contribute to knowledge accumulation of benthic fisheries. To tailor the framework, we relied on discussions among experts and a systematic literature review of benthic fisheries from 1980 to 2010. This literature review helped us refine variable definitions and provide readers with illustrative reference papers. We then illustrate the approach and its potential contributions through two studies of the emergence of self-organization in Mexico and Chile. We highlight synthetic lessons from the cases and the overall approach as well as reflect on remaining challenges to the development of a social–ecological system framework as a diagnostic tool for knowledge accumulation and synthesis.  相似文献   

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Based on observational meteorological data since A.D. 1864 and tree-ring records of debris-flow activity, this paper assesses changes in rainfall characteristics and their impact on the triggering of geomorphic events in a high-elevation watershed of the Swiss Alps since the end of the Little Ice Age. No trends are visible in the frequency of heavy rainfall events, but we observe a reduced number of heavy, short-lived rainfalls in summer and a concentration of advective storms is recorded in late summer and early fall since the late 1980s. These changes in triggering meteorological conditions resulted in a cluster of debris flows in the early decades of the twentieth century and a lowering of debris-flow activity since the mid 1990s, and may be mirroring the observed changes in persistent high-pressure systems over the Alps. We also observe intra-seasonal differences in debris-flow system response reflecting the state of the permafrost body in the source area of debris flows, allowing for very small debris flows to be released by limited rainfall inputs (<20 mm) in June and July. The same quantities of rain will not trigger debris flows in August or September, when a thick active layer of the permafrost body is capable of absorbing water. With the projected amplitude of climatic change, seasonality, return intervals and volumes of debris flows are likely to be altered. RCM projections based on the IPCC A2 scenario suggest a decrease in heavy summer rainfalls which will most likely result in a (further) reduction of the overall frequency of debris flows, leaving more time for sediment to accumulate in the channel. Such an increase of channel accumulation rates along with the projected destabilization of the steep rock-glacier body is likely, in turn, to exert control ultimately on sediment volumes released from the source areas during future events. Observations from adjacent catchments suggest that extremely large debris flows, beyond historical experience, could occur at the study site and in similar debris-flow systems of the Valais Alps originating from periglacial environments.  相似文献   

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《Climate Policy》2013,13(1):752-767
Policy-makers and scientists have raised concerns about the functioning of the Clean Development Mechanism (CDM), in particular regarding its low contribution to sustainable development, unbalanced regional and sectoral distribution of projects, and its limited contribution to global emission reductions. Differentiation between countries or project types has been proposed as a possible way forward to address these problems. An overview is provided of the different ways in which CDM differentiation could be implemented. The implications for the actors involved in the CDM are analysed, along with a quantitative assessment of the impacts on the carbon market, using bottom-up marginal abatement cost curves. The discounting of CDM credits, quota systems, or differentiated eligibility of countries could help to address several of the concerns raised. Preferential treatment may also make a limited contribution to achieving the aims of CDM differentiation by increasing opportunities for under-represented host countries. The impact on the carbon market appears to be limited for most options.  相似文献   

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Temperature reconstructions from Europe for the past 500 years based on documentary and instrumental data are analysed. First, the basic documentary data sources, including information about climate and weather-related extremes, are described. Then, the standard palaeoclimatological reconstruction method adopted here is discussed with a particular application to temperature reconstructions from documentary-based proxy data. The focus is on two new reconstructions; January–April mean temperatures for Stockholm (1502–2008), based on a combination of data for the sailing season in the Stockholm harbour and instrumental temperature measurements, and monthly Central European temperature (CEuT) series (1500–2007) based on documentary-derived temperature indices of the Czech Republic, Germany and Switzerland combined with instrumental records from the same countries. The two series, both of which are individually discussed in greater detail in subsequent papers in this special edition, are here compared and analysed using running correlations and wavelet analysis. While the Stockholm series shows a pronounced low-frequency component, the CEuT series indicates much weaker low-frequency variations. Both series are analysed with respect to three different long-period reconstructions of the North Atlantic Oscillation (NAO) and are compared with other European temperature reconstructions based on tree-rings, wine-harvest data and various climate multiproxies. Correlation coefficients between individual proxy-based series show weaker correlations compared to the instrumental data. There are also indications of temporally varying temperature cross-correlations between different areas of Europe. The two temperature reconstructions have also been compared to geographically corresponding temperature output from simulations with global and regional climate models for the past few centuries. The findings are twofold: on the one hand, the analysis reinforces the hypothesis that the index-data based CEuT reconstruction may not appropriately reflect the centennial scale variations. On the other hand, it is possible that climate models may underestimate regional decadal variability. By way of a conclusion, the results are discussed from a broader point of view and attention is drawn to some new challenges for future investigations in the historical climatology in Europe.  相似文献   

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This paper synthesizes the results from the model intercomparison exercise among regionalized global energy-economy models conducted in the context of the RECIPE project. The economic adjustment effects of long-term climate policy are investigated based on the cross-comparison of the intertemporal optimization models ReMIND-R and WITCH as well as the recursive dynamic computable general equilibrium model IMACLIM-R. A number of robust findings emerge. If the international community takes immediate action to mitigate climate change, the costs of stabilizing atmospheric CO2 concentrations at 450?ppm (roughly 530?C550?ppm-e) discounted at 3% are estimated to be 1.4% or lower of global consumption over the twenty-first century. Second best settings with either a delay in climate policy or restrictions to the deployment of low-carbon technologies can result in substantial increases of mitigation costs. A delay of global climate policy until 2030 would render the 450?ppm target unachievable. Renewables and CCS are found to be the most critical mitigation technologies, and all models project a rapid switch of investments away from freely emitting energy conversion technologies towards renewables, CCS and nuclear. Concerning end use sectors, the models consistently show an almost full scale decarbonization of the electricity sector by the middle of the twenty-first century, while the decarbonization of non-electric energy demand, in particular in the transport sector remains incomplete in all mitigation scenarios. The results suggest that assumptions about low-carbon alternatives for non-electric energy demand are of key importance for the costs and achievability of very low stabilization scenarios.  相似文献   

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In situ buoy observation data spanning four years(2008-2011) were collected and used to perform a composite analysis of the monsoon onset process in the Bay of Bengal(BoB).The sea surface temperature(SST) in the central BoB increases dramatically during the monsoon transition period and reaches its annual maximum just before the onset of the monsoon.This process is illustrated by the northward-propagating deep convection phase of the intraseasonal oscillation and the establishment of a steady southwest wind.It is argued that the SST peak plays a potential role in triggering the onset of the monsoon in the BoB and its vicinity.The general picture of the BoB monsoon onset summarized here reveals the possibility of regional land-ocean-atmosphere interaction.This possibility deserves further examination.  相似文献   

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《大气与海洋》2013,51(2):133-149
Abstract

A new mesoscale version of the regional forecast system became operational at the Canadian Meteorological Centre on 18 May 2004. The main changes to the regional modelling system include an increase in both the horizontal and vertical resolutions (15‐km horizontal resolution and 58 vertical levels instead of 24‐km resolution and 28 levels) as well as major upgrades to the physics package. The latter consist of a new condensation package, with an improved formulation of the cloudy boundary layer, a new shallow convection scheme based on a Kuo‐type closure, and the Kain and Fritsch deep convection scheme, together with a subgrid‐scale orography parametrization scheme to represent gravity wave drag and low‐level blocking effects. The new forecast system also includes a few changes to the regional data assimilation such as additional radiance data from satellites.

Objective verifications using a series of cases and parallel runs, along with subjective evaluations by CMC meteorologists, indicate significantly improved performance using the new 15‐km resolution forecast system. We can conclude from these verifications that the model exhibits a marked reduction in errors, improved predictability by about 12 hours, better forecasts of precipitation, a significant reduction in the spin‐up time, and a different implicit‐explicit partitioning of precipitation. A number of other features include: sharper precipitation patterns, better representation of trace precipitation, and general improvements of deepening lows and hurricanes. In mountainous regions, several aspects are better represented due to combined higher‐resolution orography and the low‐level blocking term.  相似文献   

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The Arctic Council is an intergovernmental forum promoting cooperation, coordination and interaction among Arctic States, Indigenous communities and peoples on issues of common importance. The rising geo-political importance of the Arctic and the onset of climate change has resulted in the Council becoming a focus of increasing interest from both inside and beyond the Arctic. This has resulted in new demands placed on the Council, attracted an increasing number of participants and instigated a period of transformation as Arctic states work to find a way to balance conflicting demands for improving the effectiveness of the Council and taking care of national interests. This paper considers if during this time of change the Council is having an impact upon the issues it was formed to address i.e. environmental protection and sustainable development. To provide answers it looks at how the Council operates and through the lens of biodiversity identifies drivers and barriers to the Councils institutional effectiveness; providing an understanding of the norms and rules which constitute the Council and which are central its problem-solving abilities. It is clear that the Council is changing and how it operates is evolving in response to the increasing attention paid to all things Arctic. However, challenges to ensuring effective outcomes from its activities remain and without clear strategies many of the Councils efforts can appear ad-hoc and without due recourse to forward planning. However, when clear and detailed plans are in place to guide the work of the Council as for biodiversity then glimpses can be seen of its potential to act as an agent of change.  相似文献   

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Adaptation gaps are shortcomings of a system responding to climate change, whereas adaptation deficits are shortcomings in providing services. These two drivers for adaptation are often in conflict in many secondary cities in the global south (SCGS). It is possible to align these seemingly conflicting drivers into a productive unity, a conceptual alignment, which is the first step in achieving harmony while implementing adaptation actions. This paper focuses on the practical aspects of implementing aligned adaptation action that leads to improvements in liveability, sustainability, and resilience of SCGS. At an abstract level, the nature of the adaptation problem is similar to the complex problems identified in various domains, such as software development, manufacturing, and supply chain management. The widely accepted “agile principles”—used in the above domains—is the basis for developing a set of twelve principles for urban adaptation, which are synthesized from numerous recent studies that have implicitly proposed or applied most of these principles to climate change adaptation in urban settings. These principles lead to four essential objectives appertaining to the process of sustainable urban adaptation. The urban agile principles are used to analyze the current state of adaptation of Can Tho City in Vietnam and to ascertain the agile ways of addressing its adaptation challenges. Analysis of the outcomes shows that harmonized approaches can simultaneously address both adaptation deficits and gaps.  相似文献   

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A five-member ensemble of regional climate model (RCM) simulations for Europe, with a high resolution nest over Germany, is analysed in a two-part paper: Part I (the current paper) presents the performance of the models for the control period, and Part II presents results for near future climate changes. Two different RCMs, CLM and WRF, were used to dynamically downscale simulations with the ECHAM5 and CCCma3 global climate models (GCMs), as well as the ERA40-reanalysis for validation purposes. Three realisations of ECHAM5 and one with CCCma3 were downscaled with CLM, and additionally one realisation of ECHAM5 with WRF. An approach of double nesting was used, first to an approximately 50 km resolution for entire Europe and then to a domain of approximately 7 km covering Germany and its near surroundings. Comparisons of the fine nest simulations are made to earlier high resolution simulations for the region with the RCM REMO for two ECHAM5 realisations. Biases from the GCMs are generally carried over to the RCMs, which can then reduce or worsen the biases. The bias of the coarse nest is carried over to the fine nest but does not change in amplitude, i.e. the fine nest does not add additional mean bias to the simulations. The spatial pattern of the wet bias over central Europe is similar for all CLM simulations, and leads to a stronger bias in the fine nest simulations compared to that of WRF and REMO. The wet bias in the CLM model is found to be due to a too frequent drizzle, but for higher intensities the distributions are well simulated with both CLM and WRF at the 50 and 7 km resolutions. Also the spatial distributions are close to high resolution gridded observations. The REMO model has low biases in the domain averages over Germany and no drizzle problem, but has a shift in the mean precipitation patterns and a strong overestimation of higher intensities. The GCMs perform well in simulating the intensity distribution of precipitation at their own resolution, but the RCMs add value to the distributions when compared to observations at the fine nest resolution.  相似文献   

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The latest iteration of Intergovernmental Panel on Climate Change (IPCC) uncertainty guidance is simpler and easier to use than the previous version. However, its primary focus remains assessing “what is at risk” under climate change, thus is most suitable for dealing with the scientific uncertainties in Working Group I and part of Working Group II findings. I distinguish between tame and complex risks, arguing that the guidance is most suited to assessing tame risks. Climate change is a complex risk, and as such as can be divided into idealized, calculated and perceived risks. While science has claims to objectivity, risk has a specific value component: when measuring gain and loss, calculated risks compete with risky options to manage those risks. The IPCC is charged with calculating risk (IPCC 2007, p22) but the communication of key findings takes place in an environment of competing perceived risks. Recommendations for managing this complex environment include separating scientific and risk-based findings, treating uncertainties for each separately; strengthening the philosophical basis of uncertainty management; application of a methodical scientific research program; clearly communicating competing findings, especially in the social sciences; and application of multiple frame to policy-relevant findings as reflected in the literature.  相似文献   

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