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751.
Lotten Wiréhn Tomasz Opach Tina-Simone Neset 《Journal of Environmental Planning and Management》2017,60(1):115-134
Nordic agriculture must adapt to climate change to reduce vulnerability and exploit potential opportunities. Integrated assessments can identify and quantify vulnerability in order to recognize these adaptation needs. This study presents a geographic visualization approach to support the interactive assessment of agricultural vulnerability to climate change. We have identified requirements for increased transparency and reflexivity in vulnerability assessments, arguing that these can be met by geographic visualization. A conceptual framework to support the integration of geographic visualization for vulnerability assessments has been designed and applied for the development of AgroExplore, an interactive tool for assessing agricultural vulnerability to climate change in Sweden. To open up the black box of composite vulnerability indices, AgroExplore enables the user to select, weight, and classify relevant indicators into sub-indices of exposure, sensitivity, and adaptive capacity. This enables the exploration of underlying indicators and factors determining vulnerability in Nordic agriculture. 相似文献
752.
Catrien J.A.M. Termeer Art Dewulf G. Robbert Biesbroek 《Journal of Environmental Planning and Management》2017,60(4):558-576
Although transformational change is a rather new topic in climate change adaptation literature, it has been studied in organisational theory for over 30 years. This paper argues that governance scholars can learn much from organisation theory, more specifically regarding the conceptualisation of change and intervention strategies. We reconceptualise the divide between transformational change and incremental change by questioning the feasibility of changes that are concurrently in-depth, large scale, and quick; and the assumption that incremental change is necessarily slow and can only result in superficial changes. To go beyond this dichotomy, we introduce the conceptualisation of continuous transformational change. Resulting intervention strategies include (1) providing basic conditions for enabling small in-depth wins; (2) amplifying small wins through sensemaking, coupling, and integrating; and (3) unblocking stagnations by confronting social and cognitive fixations with counterintuitive interventions. These interventions necessitate a modest leadership. Governing transformational change thus requires transformation of the governance systems themselves. 相似文献
753.
This paper investigates the extent and the nature of how the urban planning literature has addressed climate change adaptation. It presents a longitudinal study of 157 peer-reviewed articles published from 2000 to 2013 in the leading urban planning and design journals whose selection considered earlier empirical studies that ranked them these journals. The findings reveal that the years 2006–07 represent a turning point, after which climate change studies appear more prominently and consistently in the urban planning and design literature; however, the majority of these studies address climate change mitigation rather than adaptation. Most adaptation studies deal with governance, social learning, and vulnerability assessments, while paying little attention to physical planning and urban design interventions. This paper identifies four gaps that pertain to the lack of interdisciplinary linkages, the absence of knowledge transfer, the presence of scale conflict, and the dearth of participatory research methods. It then advocates for the advancement of participatory and collaborative action research to meet the multifaceted challenges of climate change. 相似文献
754.
利用2003-2012年3~10月秦皇岛地区5个气象站雷暴监测和雷电灾害资料,采用数理统计、天气综合分析方法,得出秦皇岛地区雷暴天气的时空尺度分布特征为:全区年雷暴发生频次总体上呈递减趋势,其中,2005年35次,2008年33次,2012年20次;6月份为全年雷暴发生的峰值时段,7月、8月次之,且与秦皇岛本地主汛期相吻合;在海岸带地区由于受海洋条件影响,个别年份雷暴最早出现在2月份,最晚出现在11月中旬;雷暴天气的日时段主要出现在下午至傍晚,占70%,夜间占20%,其他时段为10%;北部山区的雷电频次大于沿海地区,对应电力、化工等行业雷电灾害呈下降趋势,但是通讯、计算机、家电等弱电系统雷击事件呈递增趋势。 相似文献
755.
地球化学元素比值的变化不仅可以指示气候变化和环境特征,也可以揭示气候异常和突变性气候事件。本文通过对沂沭河流域沭埠岭剖面沉积物淋溶系数、残积系数、CaO/MgO、硅铝率、硅铝铁率等气候代用指标的分析,发现研究区7 470~2550 a BP期间的气候变化经历了五个阶段:(1)7 472~6 043 a BP,气候趋向温暖湿润;(2)6 043~4 801 a BP,稳定的暖湿时期;(3)4 801~3 986 a BP,气候向冷干转变;(4)3 986~3 512 a BP,不稳定时期;(5)3 512~2 552 a BP,气候不稳定的波动时期。 相似文献
756.
Zhongxiang Zhang 《Mitigation and Adaptation Strategies for Global Change》2007,12(2):203-217
The East-West Center convened the international conference on climate policy in Honolulu, Hawaii, on September 4–6, 2003. Sponsored by the Dutch Ministry of Housing, Spatial Planning and the Environment, the Japanese Ministry of the Environment, Industrial Technology Research Institute (Taiwan), and Institute for Global Environmental Strategies (Japan), this major event covered almost every important issue and featured perspectives from the most important parties and stakeholders in formulating and implementing climate policies and taking international climate negotiations further. It brought together a remarkable cross-section of world opinion on climate policy after Kyoto. This report provides a summary of each presentation and highlights discussions organized under the following six session headings: Session 1: Climate Change in Focus – From Science to Policy; Session 2: U.S. Climate Policy and Perspectives; Session 3: European Union Climate Policy and Perspectives; Session 4: Challenges for other Major Industrialized Countries; Session 5: Issues Related to Developing Countries; and Session 6: Panel Discussions: Where Do We Go from Here?. 相似文献
757.
Steven M. Wondzell Mousa Diabat Roy Haggerty 《Journal of the American Water Resources Association》2019,55(1):116-132
Simulations of stream temperatures showed a wide range of future thermal regimes under a warming climate — from 2.9°C warmer to 7.6°C cooler than current conditions — depending primarily on shade from riparian vegetation. We used the stream temperature model, Heat Source, to analyze a 37‐km study segment of the upper Middle Fork John Day River, located in northeast Oregon, USA. We developed alternative future scenarios based on downscaled projections from climate change models and the composition and structure of native riparian forests. We examined 36 scenarios combining future changes in air temperature (ΔTair = 0°C, +2°C, and +4°C), stream discharge (ΔQ = ?30%, 0%, and +30%), and riparian vegetation (post‐wildfire with 7% shade, current vegetation with 19% shade, a young‐open forest with 34% shade, and a mature riparian forest with 79% effective shade). Shade from riparian vegetation had the largest influence on stream temperatures, changing the seven‐day average daily maximum temperature (7DADM) from +1°C to ?7°C. In comparison, the 7DADM increased by 1.4°C with a 4°C increase in air temperature and by 0.7°C with a 30% change in discharge. Many streams throughout the interior western United States have been altered in ways that have substantially reduced shade. The effect of restoring shade could result in future stream temperatures that are colder than today, even under a warmer climate with substantially lower late‐summer streamflow. 相似文献
758.
Mengsheng Qin Lu Hao Lei Sun Yongqiang Liu Ge Sun 《Journal of the American Water Resources Association》2019,55(1):189-208
Reference evapotranspiration (ETo) is an important hydrometeorological term widely used in understanding and projecting the hydrological effects of future climate and land use change. We conducted a case study in the Qinhuai River Basin that is dominated by a humid subtropical climate and mixed land uses in southern China. Long‐term (1961–2012) meteorological data were used to estimate ETo by the FAO‐56 Penman–Monteith model. The individual contribution from each meteorological variable to the trend of ETo was quantified. We found basin‐wide annual ETo decreased significantly (p < 0.05) by 3.82 mm/yr during 1961–1987, due to decreased wind speed, solar radiation, vapor pressure deficit (VPD), and increased relative humidity (RH). However, due to the increased VPD and decreased RH, the ETo increased significantly (p < 0.05) in spring, autumn, and annually at a rate of 2.55, 0.56, and 3.16 mm/yr during 1988–2012, respectively. The aerodynamic term was a dominant factor controlling ETo variation in both two periods. We concluded the key climatic controls on ETo have shifted as a result of global climate change during 1961–2012. The atmospheric demand, instead of air temperature alone, was a major control on ETo. Models for accurately predicting ETo and hydrological change under a changing climate must include VPD in the study region. The shifts of climatic control on the hydrological cycles should be considered in future water resource management in humid regions. 相似文献
759.
Sarah A. Baker Andrew W. Wood Balaji Rajagopalan 《Journal of the American Water Resources Association》2019,55(4):1024-1037
We describe a new effort to enhance climate forecast relevance and usability through the development of a system for evaluating and displaying real‐time subseasonal to seasonal (S2S) climate forecasts on a watershed scale. Water managers may not use climate forecasts to their full potential due to perceived low skill, mismatched spatial and temporal resolutions, or lack of knowledge or tools to ingest data. Most forecasts are disseminated as large‐domain maps or gridded datasets and may be systematically biased relative to watershed climatologies. Forecasts presented on a watershed scale allow water managers to view forecasts for their specific basins, thereby increasing the usability and relevance of climate forecasts. This paper describes the formulation of S2S climate forecast products based on the Climate Forecast System version 2 (CFSv2) and the North American Multi‐Model Ensemble (NMME). Forecast products include bi‐weekly CFSv2 forecasts, and monthly and seasonal NMME forecasts. Precipitation and temperature forecasts are aggregated spatially to a United States Geological Survey (USGS) hydrologic unit code 4 (HUC‐4) watershed scale. Forecast verification reveals appreciable skill in the first two bi‐weekly periods (Weeks 1–2 and 2–3) from CFSv2, and usable skill in NMME Month 1 forecast with varying skills at longer lead times dependent on the season. Application of a bias‐correction technique (quantile mapping) eliminates forecast bias in the CFSv2 reforecasts, without adding significantly to correlation skill. 相似文献
760.
David Marmorek Marc Nelitz Jimena Eyzaguirre Carol Murray Clint Alexander 《Journal of the American Water Resources Association》2019,55(4):881-905
Adaptive management (AM) is a rigorous approach to implementing, monitoring, and evaluating actions, so as to learn and adjust those actions. Existing AM projects are at risk from climate change, and current AM guidance does not provide adequate methods to deal with this risk. Climate change adaptation (CCA) is an approach to plan and implement actions to reduce risks from climate variability and climate change, and to exploit beneficial opportunities. AM projects could be made more resilient to extreme climate events by applying the principles and procedures of CCA. To test this idea, we analyze the effects of extreme climatic events on five existing AM projects focused on ecosystem restoration and species recovery, in the Russian, Trinity, Okanagan, Platte, and Missouri River Basins. We examine these five case studies together to generate insights on how integrating CCA principles and practices into their design and implementation could improve their sustainability, despite significant technical and institutional challenges, particularly at larger scales. Although climate change brings substantial risks to AM projects, it may also provide opportunities, including creating new habitats, increasing the ability to quickly test flow‐habitat hypotheses, stimulating improvements in watershed management and water conservation, expanding the use of real‐time tools for flow management, and catalyzing creative application of CCA principles and procedures. 相似文献