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1.
Climate prediction: Progress,problems, and prospects   总被引:1,自引:0,他引:1  
Hundred year forecasts are made with the same models, which cannot predict the weather even several days ahead...”  相似文献   

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温带气旋是中纬度地区每日天气舞台上最重要的“演员”。在秋冬季节的中高纬度海洋上有一类快速发展的温带气旋——“爆发性气旋”,尚未受到公众的广泛关注。文章围绕这一主题,首先回顾了温带气旋研究的历史,介绍了“爆发性气旋”这一术语产生的渊源,并对多位学者给出的爆发性气旋定义进行了系统梳理,重点介绍了一个考虑风速影响的、修正的爆发性气旋定义,还总结了爆发性气旋的研究现状,最后对其未来数十年的研究前景进行了阐述展望。  相似文献   

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Paleoclimatic studies help us to gain valuable perspectives and insights into the nature and possible origins of present-day climatic variations that are beyond the reach of conventional historical weather data to provide. In this informal paper, the author lends some personal perspectives on the importance of paleoclimatic studies for the purpose of assessing the future of our climate, and illustrates this by focusing in particular on how tree-ring analyses may elucidate the chronology of changing risks of past and future outbreaks of major droughts in the American West.  相似文献   

5.
The 26th Conference of the Parties (COP26) to the United Nations Framework Convention on Climate Change (UNFCCC) was held in Glasgow a year later than scheduled, with expected outcomes achieved under a post-pandemic background. Based on the Issue-Actor-Mechanism Framework, this paper systematically evaluates the outcomes achieved at COP26 and analyzes the tendency of post-COP26 climate negotiations. Overall, with the concerted efforts of all parties, COP26 has achieved a balanced and inclusive package of outcomes and concluded six years of negotiations on the Paris Rulebook. It is fair to say that COP26 is another milestone in climate governance following the implementation of the Paris Agreement. Meanwhile, the Glasgow Climate Pact has cemented the consensus on a global commitment to accelerating climate action over the next decade and reached a breakthrough consensus on reducing coal, controlling methane, and halting deforestation. In the post-COP26 era, we still need to take concrete actions to implement the outcomes of the Paris Agreement and the Glasgow Climate Pact, innovate ways to speed up CO2 emissions reduction, and continue to strive for breakthroughs in important issues such as finance, technology, adaptation, and collaboration. In addition to avoiding the escalation of international conflicts, we need to collectively and properly handle the relationship between energy security, carbon reduction, and development and facilitate the efforts of countries to achieve their Sustainable Development Goals (SDGs), including climate-related goals. China will continue to maintain the existing multilateral mechanisms and processes for climate governance, unremittingly take concrete actions to address climate change, promote a domestic comprehensive green transition and global cooperation on carbon neutrality, and contribute constructively to global climate governance.  相似文献   

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Vulnerability, adaptation and resilience are concepts that are finding increasing currency in several fields of research as well as in various policy and practitioner communities engaged in global environmental change science, climate change, sustainability science, disaster risk-reduction and famine interventions. As scientists and practitioners increasingly work together in this arena a number of questions are emerging: What is credible, salient and legitimate knowledge, how is this knowledge generated and how is it used in decision making? Drawing on important science in this field, and including a case study from southern Africa, we suggest an alternative mode of interaction to the usual one-way interaction between science and practice often used. In this alternative approach, different experts, risk-bearers, and local communities are involved and knowledge and practice is contested, co-produced and reflected upon. Despite some successes in the use and negotiation of such knowledge for ‘real’ world issues, a number of problems persist that require further investigation including the difficulties of developing consensus on the methodologies used by a range of stakeholders usually across a wide region (as the case study of southern Africa shows, particularly in determining and identifying vulnerable groups, sectors, and systems); slow delivery of products that could enhance resilience to change that reflects not only a lack of data, and need for scientific credibility, but also the time-consuming process of coming to a negotiated understanding in science–practice interactions and, finally, the need to clarify the role of ‘external’ agencies, stakeholders, and scientists at the outset of the dialogue process and subsequent interactions. Such factors, we argue, all hinder the use of vulnerability and resilience ‘knowledge’ that is being generated and will require much more detailed investigation by both producers and users of such knowledge.  相似文献   

8.
Precipitation: Measurement,remote sensing,climatology and modeling   总被引:2,自引:0,他引:2  
This review paper deals with four aspects of precipitation: measurement, remote sensing, climatology and modeling. The measurement of precipitation is summarized in terms of the instruments that count and measure drop sizes (defined as disdrometers) and the instruments that measure an average quantity proportional to the integrated volume of an ensemble of raindrops (these instruments are normally called rain gauges). Remote sensing of precipitation is accomplished with ground based radar and from satellite retrievals and these two approaches are separately discussed. The climatology of precipitation has evolved through the years from the traditional rain gauge data analyses to the more sophisticated data bases that result from a coalescence of data and information on precipitation that is available from several sources into amalgamated products. Recently, rain observations from both ground and space have been assimilated into regional and global numerical weather prediction models aiming at improved moisture analysis and better forecasts of extreme weather events. The current status and the main outstanding issues related to precipitation forecasting are discussed, providing a basic structure for research coordination aimed at the improvement of modeling, observation and data assimilation applicable to global and regional scales.  相似文献   

9.
《Atmospheric Research》2010,95(4):512-533
This review paper deals with four aspects of precipitation: measurement, remote sensing, climatology and modeling. The measurement of precipitation is summarized in terms of the instruments that count and measure drop sizes (defined as disdrometers) and the instruments that measure an average quantity proportional to the integrated volume of an ensemble of raindrops (these instruments are normally called rain gauges). Remote sensing of precipitation is accomplished with ground based radar and from satellite retrievals and these two approaches are separately discussed. The climatology of precipitation has evolved through the years from the traditional rain gauge data analyses to the more sophisticated data bases that result from a coalescence of data and information on precipitation that is available from several sources into amalgamated products. Recently, rain observations from both ground and space have been assimilated into regional and global numerical weather prediction models aiming at improved moisture analysis and better forecasts of extreme weather events. The current status and the main outstanding issues related to precipitation forecasting are discussed, providing a basic structure for research coordination aimed at the improvement of modeling, observation and data assimilation applicable to global and regional scales.  相似文献   

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IPCC第六次评估报告(AR6)第二工作组报告第三章开展了气候变化对海洋的影响和风险,以及生态系统及其服务功能、脆弱性和适应评估。AR6明确指出,人为气候变化已经并将继续显著地改变全球和区域海洋的气候影响驱动因子,包括海温升高、海平面上升、海洋酸化和缺氧,以及营养盐浓度变化等海洋物理和化学因子。例如,20世纪80年代以来全球海洋热浪发生的频率已增加了1倍,到21世纪末期可能增加4~8倍。气候影响驱动因子的变化已经对海洋和海岸带生态系统造成了广泛而深远的影响:1)海洋变暖使得海洋物种自1950年代以来以(59.2±15.5) km/(10 a)的速率向极地方向迁移,导致热带海域生物量减少,中纬度海区热带化,极地和亚极地海区浮游植物生长期提前;2)频繁发生的海洋热浪事件已经接近甚至超过了某些海洋生物的耐受极限或其气候临界点,如暖水珊瑚的大规模白化、死亡,海草和大型海藻的大面积消失;3)海洋变暖、缺氧和酸化使得河口区生物群落结构改变,赤潮等有害藻华事件频发,近海和大洋浮游植物生物量和初级生产力下降;4)海平面上升导致海岸带红树林、盐沼和海草床等生态系统的退化;5)未来全球海洋生态系统面临的风险将不断加剧,尤其是在热带和北冰洋海区。其中,当全球升温1.5℃时(最快到21世纪40年代,SSP5-8.5情景),暖水珊瑚礁预计将减少70%~90%;当升温2℃时,几乎所有的(>99%)暖水珊瑚礁将会消失。目前人类社会采取的一些措施(如建立海洋保护区和红树林生态修复)已越来越不能应对日益增长的气候风险,迫切需要发展变革性的行动措施,推动海洋生态系统恢复力的发展,并需尽快采取强有力的减排措施以减缓全球变暖的影响。  相似文献   

12.
The Gaia Hypothesis: Fact, Theory, and Wishful Thinking   总被引:4,自引:0,他引:4  
Organisms can greatly affect their environments, and the feedback coupling between organisms and their environments can shape the evolution of both. Beyond these generally accepted facts, the Gaia hypothesis advances three central propositions: (1) that biologically mediated feedbacks contribute to environmental homeostasis, (2) that they make the environment more suitable for life, and (3) that such feedbacks should arise by Darwinian natural selection. These three propositions do not fare well under close scrutiny. (1) Biologically mediated feedbacks are not intrinsically homeostatic. Many of the biological mechanisms that affect global climate are destabilizing, and it is likely that the net effect of biological feedbacks will be to amplify, not dampen, global warming. (2) Nor do biologically mediated feedbacks necessarily enhance the environment, although it will often appear as if this were the case, simply because natural selection will favor organisms that do well in their environments – which means doing wellunder the conditions that they and their co-occurring species have created. (3) Finally, Gaian feedbacks can evolve by natural selection, but so can anti-Gaian feedbacks. Daisyworld models evolve Gaian feedback because they assume that any trait that improves the environment will also give a reproductive advantage to its carriers (over other organisms that share the same environment). In the real world, by contrast, natural selection favors any trait that gives its carriers a reproductive advantage over its non-carriers, whether it improves or degrades the environment (and thereby benefits or hinders its carriers and non-carriers alike). Thus Gaian and anti-Gaian feedbacks are both likely to evolve.  相似文献   

13.
Equity is usually interpreted in terms of the concept of justice, such that an equitable share of the atmospheric space is understood in terms of past emissions. This emphasizes the collective nature of sharing the burden of mitigation and the duty to act for those who have emitted the most. An alternative is considered: the aggregate costs and benefits to all Parties that could result from both increasing the level of collective ambition and implementing a climate regime that supports bold actions across all Parties. The regional impacts and carbon flow costs across differentiated scenarios are assessed and it is argued that the majority of developing-country Parties would be better off if a high ambition outcome to which all contributed, but some more than others. Moreover, those with middle or low emissions would have proportionally more to gain (or lose) relative to the level of ambition compared to those that have had higher emissions. The climate regime should be built on the principle of common but differentiated responsibility and respective capabilities (CBDR&RC), in which all act early even if some do much more; one that accounts for justice but does not forget hope.

Policy relevance

Differing interpretations of equity and the principles of the United Nations Framework Convention on Climate Change (UNFCCC) are discussed, with a focus on how these can enhance or hinder collective action. Whilst the climate change negotiations are usually taken as games in which one party gains and another loses, and interactions are dogged by continuous conflict, it is explored instead how negotiation responses can be framed in terms of cooperation. This would emphasize the gains that could be achieved by common but differentiated collective action, which could result in a collective avoidance of impacts. The possibilities that this shift of perspective could bring are explored by comparing costs under global cooperation (or lack of it). It is found that cooperation reduces the total costs for these regions. Thus, thinking in terms of cooperation focuses the options for negotiation on the means and interpretations of the UNFCCC principles that spur action and avoid climate impacts through collective action.  相似文献   

14.
In the United States, both scholars and practitioners have repeatedly emphasized the importance of “issue framing” for garnering public support for climate change policy. However, the debate frequently overlooks the importance of counter frames. For every framing attempt by advocates of climate policy, there will be a counter frame by the opponents of climate policy. How do counter frames influence the effectiveness of issue framing as a communication strategy? To answer this question, we report results from a survey experiment on a nationally representative sample of 1000 Americans on clean energy policy, a key policy issue in the public debate on climate change in the United States. Overall, we find that different combinations of positive and negative frames have remarkably little effect on support for clean energy policy. A follow-up on-line survey experiment with a convenience sample of 2000 Americans suggests that the counter frames are responsible for undermining the effects of the original frames.  相似文献   

15.
Martin Wolf 《Climate Policy》2013,13(6):772-783
Is it possible for all of humanity to enjoy the standards of living of today's high-income countries? What would happen if these limits were reached, perhaps because of climate change or a shortage of natural resources essential to production? How would society manage – or fail to manage – such limits? Notwithstanding the current financial and economic crises, these are perhaps the biggest questions confronting our species (and of a host of other species, who are the victims of our decisions). The article begins by considering the biggest economic event of our lifetimes – the ‘great convergence’ and its implications for the demand for resources. The discussion then turns to a specific limit on our development, climate change, which is different from most other limits, because it involves a global public good: the atmosphere. What such limits might mean for our civilization is discussed. One can persuade people to tackle climate change only if those concerned with the dangers persuade ordinary people that action will not come at the expense of their prosperity.  相似文献   

16.
Sudden disruptions, or shocks, to food production can adversely impact access to and trade of food commodities. Seafood is the most traded food commodity and is globally important to human nutrition. The seafood production and trade system is exposed to a variety of disruptions including fishery collapses, natural disasters, oil spills, policy changes, and aquaculture disease outbreaks, aquafeed resource access and price spikes. The patterns and trends of these shocks to fisheries and aquaculture are poorly characterized and this limits the ability to generalize or predict responses to political, economic, and environmental changes. We applied a statistical shock detection approach to historic fisheries and aquaculture data to identify shocks over the period 1976–2011. A complementary case study approach was used to identify possible key social and political dynamics related to these shocks. The lack of a trend in the frequency or magnitude of the identified shocks and the range of identified causes suggest shocks are a common feature of these systems which occur due to a variety, and often multiple and simultaneous, causes. Shocks occurred most frequently in the Caribbean and Central America, the Middle East and North Africa, and South America, while the largest magnitude shocks occurred in Asia, Europe, and Africa. Shocks also occurred more frequently in aquaculture systems than in capture systems, particularly in recent years. In response to shocks, countries tend to increase imports and experience decreases in supply. The specific combination of changes in trade and supply are context specific, which is highlighted through four case studies. Historical examples of shocks considered in this study can inform policy for responding to shocks and identify potential risks and opportunities to build resilience in the global food system.  相似文献   

17.
All sectors face decarbonization for a 2 °C temperature increase to be avoided. Nevertheless, meaningful policy measures that address rising CO2 from international aviation and shipping remain woefully inadequate. Treated with a similar approach within the United Nations Framework Convention on Climate Change (UNFCCC), they are often debated as if facing comparable challenges, and even influence each others’ mitigation policies. Yet their strengths and weaknesses have important distinctions. This article sheds light on these differences so that they can be built upon to improve the quality of debate and ensuing policy development. The article quantifies ‘2 °C’ pathways for these sectors, highlighting the need for mitigation measures to be urgently accelerated. It reviews recent developments, drawing attention to one example where a change in aviation mitigation policy had a direct impact on measures to cut CO2 from shipping. Finally, the article contrasts opportunities and barriers towards mitigation. The article concludes that there is a portfolio of opportunities for short- to medium-term decarbonization for shipping, but its complexity is its greatest barrier to change. In contrast, the more simply structured aviation sector is pinning too much hope on emissions trading to deliver CO2 cuts in line with 2 °C. Instead, the solution remains controversial and unpopular – avoiding 2 °C requires demand management.

Policy relevance

The governance arrangements around the CO2 produced by international aviation and shipping are different from other sectors because their emissions are released in international airspace and waters. Instead, through the Kyoto Protocol, the International Civil Aviation Authority (ICAO) and the International Maritime Organization (IMO) were charged with developing policies towards mitigating their emissions. Slow progress to date, coupled with strong connections with rapidly growing economies, has led to the CO2 from international transport growing at a higher rate than the average rate from all other sectors. This article considers this rapid growth, and the potential for future CO2 growth in the context of avoiding a 2 °C temperature rise above pre-industrial levels. It explores similarities and differences between these two sectors, highlighting that a reliance on global market-based measures to deliver required CO2 cuts will likely leave both at odds with the overarching climate goal.  相似文献   

18.
The feasibility of two low-carbon society (LCS) scenarios, one with and one without nuclear power and carbon capture and storage (CCS), is evaluated using the AIM/Enduse[Global] model. Both scenarios suggest that achieving a 50% emissions reduction target (relative to 1990 levels) by 2050 is technically feasible if locally suited technologies are introduced and the relevant policies, including necessary financial transfers, are appropriately implemented. In the scenario that includes nuclear and CCS options, it will be vital to consider the risks and acceptance of these technologies. In the scenario without these technologies, the challenge will be how to reduce energy service demand. In both scenarios, the estimated investment costs will be higher in non-Annex I countries than in Annex I countries. Finally, the enhancement of capacity building to support the deployment of locally suited technologies will be central to achieving an LCS.

Policy relevance

Policies to reduce GHG emissions up to 2050 are critical if the long-term target of stabilizing the climate is to be achieved. From a policy perspective, the cost and social acceptability of the policy used to reduce emissions are two of the key factors in determining the optimal pathways to achieve this. However, the nuclear accident at Fukushima highlighted the risk of depending on large-scale technologies for the provision of energy and has led to a backlash against the use of nuclear technology. It is found that if nuclear and CCS are used it will be technically feasible to halve GHG emissions by 2050, although very costly. However, although the cost of halving emissions will be about the same if neither nuclear nor CCS is used, a 50% reduction in emissions reduction will not be achievable unless the demand for energy service is substantially reduced.  相似文献   

19.
The determination of the anthropogenic impact on the thermal regime of a megalopolis is discussed. The nominal boundaries of the megalopolis thermal effects are determined taking into account orographic and landscape effects and the variability of temperature difference between the center of the city and its suburbs. It is proposed to use the data of stations located within 40-50 km from the urban agglomeration boundaries for calculating the anthropogenic component of the urban heat island. The parameters of the heat island in Moscow are determined from the measurement data on maximum and minimum daily surface air temperature in 2012-2016, and their significant seasonal and intradaily variability is revealed. It is corroborated that anthropogenic causes for the higher air temperature in Moscow as compared with suburbs during the cold season are the release and loss of heat of heating systems; in the absence of snow cover the anthropogenic effect of these sources is enhanced by the thermal radiation of the urban surface.  相似文献   

20.
‘Agrodiversity’, a term of the 1990s, refers to interactions between agricultural management practices, farmers’ resource endowments, bio-physical resources, and species. If it is to have practical use, it must be codified as a basis for analysis. A division into overlapping and interrelated components is proposed, which distinguish spatial and temporal variations as well as related developmental issues such as livelihoods and food security.  相似文献   

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