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1.
A Model to Calculate what a Remote Sensor ‘Sees’ of an Urban Surface   总被引:2,自引:0,他引:2  
Whilst the measurement of radiation emissions from a surface is relatively straightforward, correct interpretation and proper utilization of the information requires that the surface area seen be known accurately. This becomes non-trivial when the target is an urban surface, due to its complex three-dimensional form and the different thermal, radiative and moisture properties of its myriad surface facets. The geometric structure creates shade patterns in combination with the solar beam and obscures portions of the surface from the sensor, depending on where it is pointing and its field-of-view (FOV). A model to calculate these surface-sensor-sun relations (SUM) is described. SUM is tested against field and scale model observations, and theoretical calculations, and found to perform well. It can predict the surface area seen by a sensor of known FOV pointing in any direction when placed at any point in space above a specified urban surface structure. Moreover, SUM can predict the view factors of the roof, wall and ground facets seen and whether they are sunlit or shaded at any location and time of day. SUM can be used to determine the optimal placement and orientation of remote sensors to study urban radiation emissions; if the facet temperatures are known or modelled it can calculate the average temperature of the system, and it can determine the directional variation of temperature (anisotropy) due to any particular surface-sensor-sun geometric combination. The present surface geometry used in SUM is relatively simple, but there is scope to make it increasingly realistic.  相似文献   

2.
The question of whether and to what extent global warming may be changing tropical cyclone (TC) activity is of great interest to decision makers. The presence of a possible climate change signal in TC activity is difficult to detect because interannual variability necessitates analysis over longer time periods than available data allow. Projections of future TC activity are hindered by computational limitations and uncertainties about changes in regional climate, large scale patterns, and TC response. This review discusses the state of the field in terms of theory, modeling studies and data. While Atlantic TCs have recently become more intense, evidence for changes in other basins is not persuasive, and changes in the Atlantic cannot be clearly attributed to either natural variability or climate change. However, whatever the actual role of climatic change, these concerns have opened a “policy window” that, if used appropriately, could lead to improved protection against TCs.  相似文献   

3.
厄尔尼诺又称厄尔尼诺海流,是太平洋赤道带大范围内海洋和大气相互作用后失去平衡而产生的一种大气现象。它的基本特征是太平洋沿岸的海面水温异  相似文献   

4.
Antony Millner 《Climatic change》2012,110(1-2):143-167
The role of short- and long-term climate predictions in determining the success of adaptation to climate change is investigated. A simple theoretical model that captures the relationship between adaptive performance, decision structure, and prediction accuracy at different temporal scales is developed, and its implications deduced. It is shown that users who face high adjustment costs (i.e. are inflexible) depend more heavily on accurate long-term predictions than those who are able to adjust their adaptation strategies at low cost. However, the constraints on the accuracy of long-term predictions in order for them to be ‘accurate enough’ to be recommended unreservedly are strongest for precisely those users who desire them most. There are thus intrinsic structural limitations to the utility of long-term predictions for adaptive decision making. In addition, the heterogeneous dependence of adaptive performance on predictions at different temporal scales gives rise to a resource allocation problem for investments aimed at improving predictions so as to maximize their social benefits. It is suggested that an explicit distributional framework that matches users’ needs with scientific feasibility is needed in order to guide such investments, and key issues any such framework will need to address are discussed.  相似文献   

5.
Urban areas are pivotal to global adaptation and mitigation efforts. But how do cities actually perform in terms of climate change response? This study sheds light on the state of urban climate change adaptation and mitigation planning across Europe. Europe is an excellent test case given its advanced environmental policies and high urbanization. We performed a detailed analysis of 200 large and medium-sized cities across 11 European countries and analysed the cities’ climate change adaptation and mitigation plans. We investigate the regional distribution of plans, adaptation and mitigation foci and the extent to which planned greenhouse gas (GHG) reductions contribute to national and international climate objectives. To our knowledge, it is the first study of its kind as it does not rely on self-assessment (questionnaires or social surveys). Our results show that 35 % of European cities studied have no dedicated mitigation plan and 72 % have no adaptation plan. No city has an adaptation plan without a mitigation plan. One quarter of the cities have both an adaptation and a mitigation plan and set quantitative GHG reduction targets, but those vary extensively in scope and ambition. Furthermore, we show that if the planned actions within cities are nationally representative the 11 countries investigated would achieve a 37 % reduction in GHG emissions by 2050, translating into a 27 % reduction in GHG emissions for the EU as a whole. However, the actions would often be insufficient to reach national targets and fall short of the 80 % reduction in GHG emissions recommended to avoid global mean temperature rising by 2 °C above pre-industrial levels.  相似文献   

6.
The Stern Review has played an enormous role in making the world of business aware of the challenge of long-term climate change. In order to make real progress on the basis of this awareness, it is important to pay attention to the difference between human suffering and losses of gross domestic product (GDP). The Review has compared climate change to experiences of suffering like World War I. That war, however, hardly affected global GDP. The long-term damages to be expected from business-as-usual greenhouse gas emissions include loss of the coastal cities of the world over the next millennia. This would be an act of unprecedented barbarism, regardless of whether it would slow down economic growth or perhaps even accelerate it. Business leaders worried about climate change need to pay attention to the tensions between ethical and economic concerns. Otherwise, a credibility crisis threatens global climate policy. An important step to establish the credibility needed for effective climate policy will be to gradually move towards a regime where emission permits are auctioned, not handed out as hidden subsidies. The revenues generated by permit auctions should be used to establish a global system of regional climate funds.  相似文献   

7.
In the past 5 years there has been a proliferation of efforts to map climate change “hotspots” — regions that are particularly vulnerable to current or future climate impacts, and where human security may be at risk. While some are academic exercises, many are produced with the goal of drawing policy maker attention to regions that are particularly susceptible to climate impacts, either to mitigate the risk of humanitarian crises or conflicts or to target adaptation assistance. Hotspots mapping efforts address a range of issues and sectors such as vulnerable populations, humanitarian crises, conflict, agriculture and food security, and water resources. This paper offers a timely assessment of the strengths and weaknesses of current hotspots mapping approaches with the goal of improving future efforts. It also highlights regions that are anticipated, based on combinations of high exposure, high sensitivity and low adaptive capacity, to suffer significant impacts from climate change.  相似文献   

8.
The MAPS programme, which seeks to deepen mitigation ambition in developing countries, is engaged in exploring the concepts of Nationally Appropriate Mitigation Actions (NAMAs) and Low Carbon Development Strategies (LCDS) from a developing country perspective. Here, climate mitigation practitioners in six developing countries were surveyed for their understanding of these concepts (anonymous, personal communications with climate mitigation practitioners in Argentina, Brazil, Chile, Colombia, India, and South Africa). It is found that there is much scope for clarity and conceptual elaboration in this policy space. NAMAs are largely interpreted as mitigation activities packaged for submission to the United Nations Framework Convention on Climate Change (UNFCCC) registry, but are not held to constitute the full set of mitigation activity in a developing country. New terminology may be needed to describe this broader set. A tighter interpretation of LCDS to distinguish between a strategic or coordinating policy action may be useful. Other themes arising include the way ‘national appropriateness’ is reflected in the concepts, and the role of international policy in deepening mitigation action in developing countries.  相似文献   

9.
新疆呼图壁河“99·7’’洪水成因分析   总被引:1,自引:0,他引:1  
依据有关气象与水文资料对新疆呼图壁河1999年7月20日12时发生的大洪水进行了分析,从而揭示呼图壁河“99.7”洪水发生、发展的成因。  相似文献   

10.
由广西气象学会、广西水利学会联合主办的“’97北回归线夏令营”在南宁和桂平举行,从S月11至15目共历时5天。营员来自区气象局、区水利电力厅的机关和直属单位职工子弟,区气象局林少雄副局长担任总营营长。为了办好这届夏令营,区气象局、区水利电力厅、区气象台、区水电学校、区人降办等单位在人力、物力、财力等方面都给予了大力的支持。五天的夏令营生活,通过参观区气象台、桂平市石咀镇北回归线标志塔、金田村太平天国起义旧址、桂平西江航运枢纽工程、桂平西山、大藤荚的自然景观和听取有关专家的科普知识介绍。使营员们了解了气…  相似文献   

11.
To date, efforts by non-governmental organizations to encourage reduced meat consumption in light of climate change have been quite limited, particularly among environmental non-governmental organizations. This study sought to examine the factors influencing non-governmental organization decisions to establish and sustain dedicated public education and/or policy advocacy campaigns on this issue. More specifically, a grounded theory approach was used to examine environmental, food-focused, and animal protection non-governmental organizations in the U.S., Sweden, and Canada. Results indicate that the relatively limited degree of engagement is primarily attributable to the fact that few non-governmental organization staffers felt that addressing meat consumption within a climate change context was a part of their core missions. Reduced meat consumption was also seen as an issue with limited social and political appeal. Further, many environmental non-governmental organizations appeared to be reluctant to mount campaigns explicitly encouraging personal behavior change of any type. Cross- non-governmental organization collaboration or the creation of additional non-governmental organizations with missions focused on this specific issue may be needed to increase the level of campaigning on this issue.  相似文献   

12.
13.
Over the century of ‘Climatic Change’ volumes and the 33 years that they span the climate has changed. Here I consider the challenge of interdisciplinary communication to which the first 99 volumes of this journal are dedicated. Have we succeeded and have climatic change researchers shared findings with a broader audience? If this journal has been successful, should the editorial board and publishers now consider new modes of communicating research to a still wider public, say by hiring a communication cartoonist or with an interactive blog?  相似文献   

14.
A changing climate will exacerbate many of the problems currently faced by California’s public health institutions. The public health impacts of climate change include: an increase in extreme heat events and associated increases in heat-related morbidity and mortality, increases in the frequency and severity of air pollution episodes, shifts in the range and incidence of vector-borne diseases, increases in the severity of wildfire, increased risks of drought and flooding, and other extreme events. This article assesses the readiness of California’s public health institutions to cope with the changes that will accompany a changing climate and how they relate to strategies laid out in the state’s Climate Adaptation Strategy. County-level health offices are the front line actors to preserve public health in the face of numerous threats, including climate change. Survey results show that local health officers in California believe that climate change is a serious threat to public health, but feel that they lack the funding and resources to reduce this risk. Local health agencies also have a number of tools in place that will be helpful for preparing for a changing climate.  相似文献   

15.
Successful adaptation assumes the availability of appropriate information for groups potentially impacted by climate change. This research examines information available to help farmers in the Canadian Prairies to adapt, with focus on information related to soil and water conservation practices, such as preserving wetlands and maintaining shelterbelts and groundcover, considered particularly important for this region. Results of 28 semi-structured interviews carried out with producers in two Prairie provinces, Alberta and Manitoba, revealed that information regarding soil and water conservation practices comes from a variety of sources. These included industry, government, producer and conservation organizations, social sources of information and personal experience, and media. Producers were more open to new practices when they could learn them through observation, trials, and two-way dialogue. There appears to be a general lack of producer organization involvement, and dearth of government information, direction, and coordination for climate change adaptation. Information from government and producer organizations can be important for the co-production of knowledge that can lead to successful adaptation.  相似文献   

16.
Arnol’d’s second nonlinear stability criterion for motions governed by a general multilayer quasi-geostiophic model is established. The model allows arbitrary density jumps and layer thickness, and at the top and the bottom of the fluid, the boundary condition is either free or rigid. The criterion is obtained by the establishment of the upper bounds of disturbance energy and potential enstrophy in terms of the initial disturbance field.  相似文献   

17.
Researchers and policy makers increasingly recognize the need to adapt to future changes in climate, given that past emissions of greenhouse gases have already committed the world to some level of climate change. However, the current understanding of the costs and benefits of adaptation measures is still fairly rudimentary, and far from comprehensive. An assessment is presented of the current state of knowledge on the magnitude of adaptation costs in the United States. While incomplete, the studies suggest that adaptation cost could be as high as tens or hundreds of billions of dollars per year by the middle of this century. Key studies are identified in each sector, and the cost estimates and approaches to cost estimation are surveyed. Methodological issues are highlighted in interpreting, comparing, and aggregating adaptation cost estimates. Policy recommendations are made along with appropriate steps to make future adaptation cost studies more comparable within and across sectors and more accessible and relevant to policy and decision makers.

Policy relevance

Designing and implementing climate change adaptation policy requires good information about the effectiveness and cost of available adaptive options. The current state of knowledge on adaptation costs in the United States is assessed and significant gaps in the literature are highlighted – particularly in terms of sectoral and geographic coverage – as well as inconsistencies in methodologies and assumptions that hamper comparison across studies. Critical steps are identified that can be taken to make adaptation cost studies more accessible and useful to decision makers. The findings and recommendations are relevant to adaptation cost studies globally, not just in the United States.  相似文献   

18.
A large portion of foreign assistance for climate change mitigation in developing countries is directed to clean energy facilities. To support international mitigation goals, however, donors must make investments that have effects beyond individual facilities. They must reduce barriers to private-sector investment by generating information for developers, improving relevant infrastructure, or changing policies. We examine whether donor agencies target financing for commercial-scale wind and solar facilities to countries where private investment in clean energy is limited and whether donor investments lead to more private investments. On average, we find no positive evidence for these patterns of targeting and impact. Coupled with model results that show feed-in tariffs increase private investment, we argue that donor agencies should reallocate resources to improve policies that promote private investment in developing countries, rather than finance individual clean energy facilities.

Policy relevance

We suggest that international negotiations could usefully shift the focus of climate change finance towards adaptation in exchange for mitigation-improving policy reforms in developing countries. There is little evidence that mitigation-related financing is having broader effects on energy production, so new financial arrangements should be the focus of future negotiations. Additionally, international donors should focus efforts on reforming policies to attract private investment.  相似文献   

19.
This empirical study assesses the relationship between the characteristics of developing countries and the amount of official climate mitigation finance inflow. A two-part model and robustness checks were used to analyse 1998–2010 Rio Marker data on 180 developing countries. The results show that developing countries with higher CO2 intensity, larger carbon sinks, lower per capita gross domestic product (GDP) and good governance tend to be selected as recipients of climate mitigation finance, and receive more of it. CO2 emission is not used as a determinant of mitigation finance until the actual financial disbursement. Poverty aid tends to be allocated to countries with low CO2 emissions, possibly to avoid diverting aid from poorer developing countries. However, such a diversion is unavoidable if the share of mitigation finance in climate finance and in overall official development assistance (ODA) continues to escalate. This study calls for an equitable allocation of total ODA mitigation and adaptation finance in addition to the 0.7% ODA/gross national income target, and for transparent criteria and the verification of reporting on the allocation of mitigation finance.  相似文献   

20.
Consumers’ knowledge about climate change   总被引:2,自引:2,他引:0  
Several studies have unveiled various misconceptions about climate change that the public holds, for instance, confusion about climate change and ozone depletion. However, so far, there has been no uniform and standardized way to measure climate-related knowledge, which complicates comparisons between different countries or samples. To develop an extensive knowledge scale, we therefore examined the Swiss public??s understanding of climate change in a mail survey and related this scale to attitudes toward climate change. We thereby aimed to consider a broad range of climate-related knowledge, namely physical knowledge about CO2 and the greenhouse effect, knowledge about climate change and its causes, knowledge about the expected consequences of climate change, and action-related knowledge. The questionnaire included items of different degrees of difficulty, ranging from knowledge that is covered by newspapers to experts?? knowledge. Our findings indicate that people still hold several misconceptions, although people??s knowledge related to CO2 seems to have increased compared to previous studies. Of all knowledge subscales, knowledge about climate change and causes was most strongly related to attitudes toward climate change.  相似文献   

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