共查询到19条相似文献，搜索用时 156 毫秒
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新媒体环境下,以雾霾为切入点的环境问题迅速成为公众、媒体和政府关注的焦点,各利益相关方表现出对雾霾科学信息的不同需求。科学成果在传播内容及其表现形式、传播主体、传播路径等方面呈现出新的模式：成果传播的受众由少至多,成果传播的内容和形式不断多样化,成果数量呈现爆发式增长,更新速率不断加快,传播主体大众化,传播路径由单一向多元化转变;新媒体在有助于推动公众参与环境保护的同时,也给科学传播工作带来了挑战,建议有效利用新媒体的传播渠道,加强环境信息及科学知识的公开和普及,以提高环境保护和治理的能力。 相似文献
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辽宁北部典型流域水生态功能区水生态安全评价 总被引：1，自引：0，他引：1
基于流域水生态功能分区的水生态安全评价是指导流域水生态“分类、分区”综合管理的前提,本文在流域中小尺度上依据水生态空间格局分异的自然特征和社会属性,以辽河流域的清河和凡河支流为对象,在流域水生态功能三级分区的基础上,运用“压力-状态-响应模型”（PSR）,通过对流域社会经济压力指标、环境压力指标、城市发展指标、资源环境发展指标、投资指标、治理指标等因素分析,筛选出13个评价指标。利用生态安全综合指数法,将流域水生态安全划分为极不安全、不安全、基本安全、安全、非常安全五个级别。其中,清河流域Ⅳ-5-9、Ⅳ-5-10、Ⅳ-5-11、Ⅳ-5-12、Ⅳ-5-14区处于基本安全,Ⅳ-5-8、Ⅳ-5-13属于不安全;凡河流域4个水生态功能三级区中,Ⅳ-5-1、Ⅳ-5-2、Ⅳ-5-3区属于基本安全、Ⅳ-5-4区为较安全。基于水生态功能分区的水生态安全评价和级别划分可为辽河流域水生态保护与流域生态管理提供科学依据。 相似文献
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对内陆干旱区生态环境系统的结构与功能、生态环境的近期变化及其成因、生态环境系统与气候系统的关系、生态环境保护、治理、建设与经济社会协调发展的基本关系等进行综合分析和评估。 相似文献
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分3个方面介绍增水防雹火箭弹的工作原理、技术参数和标识,加强对增水防雹火箭的了解和认识. 相似文献
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Linda D. Mortsch 《Climatic change》1998,40(2):391-416
Great Lakes shoreline wetlands are adapted to a variable water supply. They require the disturbance of water level fluctuations to maintain their productivity. However, the magnitude and rate of climate change could alter the hydrology of the Great Lakes and affect wetland ecosystems. Wetlands would have to adjust to a new pattern of water level fluctuations; the timing, duration, and range of these fluctuations are critical to the wetland ecosystem response. Two "what if" scenarios: (1) an increased frequency and duration of low water levels and (2) a changed temporal distribution and amplitude of seasonal water levels were developed to assess the sensitivity of shoreline wetlands to climate change. Wetland functions and values such as wildlife, waterfowl and fish habitat, water quality, areal extent, and vegetation diversity are affected by these scenarios. Key wetlands are at risk, particularly those that are impeded from adapting to the new water level conditions by man-made structures or geomorphic conditions. Wetland remediation, protection and enhancement policies and programs must consider climate change as an additional stressor of wetlands. 相似文献
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Andrew D. Gronewold Vincent Fortin Brent Lofgren Anne Clites Craig A. Stow Frank Quinn 《Climatic change》2013,120(4):697-711
The North American Laurentian Great Lakes hold nearly 20 % of the earth’s unfrozen fresh surface water and have a length of coastline, and a coastal population, comparable to frequently-studied marine coasts. The surface water elevations of the Great Lakes, in particular, are an ideal metric for understanding impacts of climate change on large hydrologic systems, and for assessing adaption measures for absorbing those impacts. In light of the importance of the Great Lakes to the North American and global economies, the Great Lakes and the surrounding region also serve as an important benchmark for hydroclimate research, and offer an example of successful adaptive management under changing climate conditions. Here, we communicate some of the important lessons to be learned from the Great Lakes by examining how the coastline, water level, and water budget dynamics of the Great Lakes relate to other large coastal systems, along with implications for water resource management strategies and climate scenario-derived projections of future conditions. This improved understanding fills a critical gap in freshwater and marine global coastal research. 相似文献
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Climate change impacts on Laurentian Great Lakes levels 总被引：1，自引：1，他引：1
Holly C. Hartmann 《Climatic change》1990,17(1):49-67
Scenarios of water supplies reflecting CO2-induced climatic change are used to determine potential impacts on levels of the Laurentian Great Lakes and likely water management policy implications. The water supplies are based on conceptual models that link climate change scenarios from general circulation models to estimates of basin runoff, overlake precipitation, and lake evaporation. The water supply components are used in conjunction with operational regulation plans and hydraulic routing models of outlet and connecting channel flows to estimate water levels on Lakes Superior, Michigan, Huron, St. Clair, Erie, and Ontario. Three steady-state climate change scenarios, corresponding to modeling a doubling of atmospheric CO2, are compared to a steady-state simulation obtained with historical data representing an unchanged atmosphere. One transient climate change scenario, representing a modeled transition from present conditions to doubled CO2 concentrations, is compared to a transient simulation with historical data. The environmental, socioeconomic, and policy implications of the climate change effects modeled herein suggest that new paradigms in water management will be required to address the prospective increased allocation conflicts between users of the Great Lakes.GLERL Contribution No. 645. 相似文献
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Transposed Climates for Study of Water Supply Variability on the Laurentian Great Lakes 总被引：2，自引：0，他引：2
Kenneth E. Kunkel Stanley A. Changnon Thomas E. Croley II Frank H. Quinn 《Climatic change》1998,38(4):387-404
Hydrological models of the Great Lakes basin were used to study the sensitivity of Great Lakes water supplies to climate warming by driving them with meteorological data from four U.S. climate zones that were transposed to the basin. Widely different existing climates were selected for transposition in order to identify thresholds of change where major impacts on water supplies begin to occur and whether there are non-linear responses in the system. The climate zones each consist of 43 years of daily temperature and precipitation data for 1,000 or more stations and daily evaporation-related variables (temperature, wind speed, humidity, cloud cover) for approximately 20–35 stations. A key characteristic of these selected climates was much larger variability in inter-annual precipitation than currently experienced over the Great Lakes. Climate data were adjusted to simulate lake effects; however, a comparison of hydrologic results with and without lake effects showed that there was only minor effects on water supplies. 相似文献
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Yongchun Zhuu 《气象科学》2000,21(3)
1 INTRODUCTIONA Growing concern over the potential effects of a possible change in the future climatecontinues to motivate research into cycles,variability,and trends in the temperatures of theGreat L akes.These temperatures have a major influence on the water balance of the GreatL akes watershed through evaporation and the forcing of atmospheric effects.Before a futuretemperature structure and cycle can be estimated,the present water temperature climatologymust be sucessfully simulated… 相似文献
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Using Decision Analysis to Include Climate Change in Water Resources Decision Making 总被引：1，自引：1，他引：0
Is the prospect of possible climate change relevant to water resources decisions being made today? And, if so, how ought that prospect be considered? These questions can be addressed by decision analysis, which we apply to two investments in the Great Lakes region: a regulatory structure for Lake Erie, and breakwaters to protect Presque Isle State Park, PA. These two decisions have the elements that potentially make climate change relevant: long lived, "one shot" investments; benefits or costs that are affected by climate-influenced variables; and irreversibilities. The decision analyses include the option of waiting to obtain better information, using Bayesian analysis to detect whether climate change has altered water supplies. The analyses find that beliefs about climate change can indeed affect optimal decisions. Furthermore, ignoring the possibility of climate change can lead to significant opportunity losses—in the cases here, as much as 10% or more of the construction cost. Yet the consequences of climate uncertainty for Great Lakes management do not appear to be qualitatively different from those of other risks, and thus do not deserve different treatment. The methods of sensitivity analysis, scenario planning, and decision analysis, all of which are encouraged under US federal guidelines for water planning, are applicable. We recommend increased use of decision trees and Bayesian analysis to consider not only climate change risks, but also other important social and environmental uncertainties. 相似文献
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Abstract We have made a preliminary study of cloud‐to‐ground lightning over southern Ontario and the adjoining Great Lakes region. The lightning data set, using magnetic direction finding, is sufficiently accurate to study lightning climatology. Cloud‐to‐ground flash totals have been found for the three warm seasons 1989–91. A large variation in flash total, lightning‐day frequency and number of high flash density storms occurs over the area, with the maximum in southwestern Ontario. The area of the maximum also has a strong diurnal cycle and relatively few positive flashes. Several physical causes may contribute to this. Lake areas usually have slightly fewer flashes than nearby land areas and warm water usually has more flashes than cold water. The Great Lakes do produce more lightning than ocean areas. Convergence lines of lake breezes and other lake circulations can, however, be sites for storms with intense lightning. High surface temperature and moisture leads to an increase in lightning generation. Over land, upslope flow increases lightning‐producing storms and downslope flow decreases them. High flash density storms may be favoured by smooth rather than rough ground, and by open farmland rather than forest. On the other hand, there does not seem to be a clear urban effect increasing lightning in the Great Lakes 相似文献
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F.M. Boyce 《大气与海洋》2013,51(3):195-206
Abstract The paper discusses the possibility of extracting electrical energy from the thermal energy stored in stratified lakes. Three situations are examined, an open lake or pond acting as a solar collector, a combination of waste heat and solar energy, and selective withdrawal of warm and cold streams from a stratified hydroelectric reservoir. Approximate calculations of the energy returns are made for typical conditions. The returns are limited by environmental factors as well as a short operating season. By using the deep stratified Great Lakes (Superior, Huron, Michigan and Ontario) as solar collectors, a few thousand megawatts of electrical power could be produced in the Great Lakes Basin during the summer months. This power could be produced on a year‐round basis by a single large nuclear generating station. 相似文献