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1.
Sun  Jie  Wu  Zhaohua 《Climate Dynamics》2020,54(3):1383-1405
Climate Dynamics - Tropical waves have relatively large amplitudes in and near convective systems, attenuating as they propagate away from the area where they are generated due to the dissipative...  相似文献   

2.
This article presents a small community of High Arctic hunters (the Inughuit in North West Greenland) who have always had to negotiate climatic changes with great impact on their living conditions. This points us toward the natural-social entanglements implied in the notion of the Anthropocene, and to the new intellectual challenges that both natural and social scientists are facing in relation to the current climatic changes. These challenges are discussed through the case of the Inughuit with whom the author has worked over many years. Departing from their dire situation in the 19th century, when they were first described and became known to outsiders, it is shown how flexibility and mobility were always preconditions for survival in this environment. Then, they were trapped in too much ice, while now they have to negotiate a rapidly melting environment. In both cases their response is deeply implicated in their sense of who they were and are, also in relation to a larger world.  相似文献   

3.
空气污染与气候变化   总被引:24,自引:1,他引:23  
近50年来,全球气候变化主要由大气温室气体浓度的日益增加引起,而空气污染主要由悬浮于空气中的大气气溶胶粒子造成,它们都主要由矿物燃料的燃烧排放形成.近年的研究表明,大气气溶胶粒子也具有气候效应:一是通过散射和吸收太阳光,减少到达地面的太阳辐射而具有降冷作用,可抵消一部分由温室气体造成的变暖作用;二是可以作为云中凝结核改变云微物理过程和降水性质,改变大气的水循环.大气气溶胶对于经济社会的许多方面,如农业、水资源、人体健康、城市化等也表现出重要的影响.由于空气污染和气候变化在很大程度上有共同的原因,即主要都是由矿物燃料燃烧的排放造成,因而减轻和控制空气污染与减少温室气体排放保护气候在行动上应是一致的.为了从经济上得到最大的节约和获得双赢的效果,应该采取协同应对空气污染和气候变化的减排战略,即应该采取统一的而不是分离的科学研究和应对战略.  相似文献   

4.
An earlier discussion of the wind stress measurements of the 1986 HEXMAX experiment off the Dutch coast left some uncertainty about the actual relationship between the stress and the wave field. In this paper we try to find a more definitive answer by looking at the consequences for gradients of wind speed, stress and phase speed of the waves if we assume the Charnock coefficient to be either a constant or to have an inverse wave age dependence. It turns out that both assumptions have a wind speed range where they produce coherent results, but that they break down when the wave length exceeds a value that is related to the water depth.  相似文献   

5.
Adaptation is an important element on the climate change policy agenda. Integrated assessment models, which are key tools to assess climate change policies, have begun to address adaptation, either by including it implicitly in damage cost estimates, or by making it an explicit control variable. We analyze how modelers have chosen to describe adaptation within an integrated framework, and suggest many ways they could improve the treatment of adaptation by considering more of its bottom-up characteristics. Until this happens, we suggest, models may be too optimistic about the net benefits adaptation can provide, and therefore may underestimate the amount of mitigation they judge to be socially optimal. Under some conditions, better modeling of adaptation costs and benefits could have important implications for defining mitigation targets.  相似文献   

6.
Stochastic weather generators are statistical models that produce random numbers that resemble the observed weather data on which they have been fitted; they are widely used in meteorological and hydrologi- cal simulations. For modeling daily precipitation in weather generators, first-order Markov chain-dependent exponential, gamma, mixed-exponential, and lognormal distributions can be used. To examine the perfor- mance of these four distributions for precipitation simulation, they were fitted to observed data collected at 10 stations in the watershed of Yishu River. The parameters of these models were estimated using a maximum-likelihood technique performed using genetic algorithms. Parameters for each calendar month and the Fourier series describing parameters for the whole year were estimated separately. Bayesian infor- mation criterion, simulated monthly mean, maximum daily value, and variance were tested and compared to evaluate the fitness and performance of these models. The results indicate that the lognormal and mixed-exponential distributions give smaller BICs, but their stochastic simulations have overestimation and underestimation respectively, while the gamma and exponential distributions give larger BICs, but their stochastic simulations produced monthly mean precipitation very well. When these distributions were fitted using Fourier series, they all underestimated the above statistics for the months of June, July and August.  相似文献   

7.
A commentary on the recent CO2-climate controversy   总被引:1,自引:0,他引:1  
Suggestions have persisted over the past few years that, contary to conventional estimates, increasing levels of atmospheric carbon dioxide will produce negligible warming of the earth's surface, or might even result in surface cooling. In the present paper we reexamine several aspects of these suggestions and illustrate that they are either founded in various violations of the first law of thermodynamics, or that they are based upon misinterpretations of historical data.  相似文献   

8.
The use of documentary sources has proven useful to identify extremeclimatic events and their variability during the pre-instrumental period. Theaim of this paper is to describe iceberg sightings in the Western SouthAtlantic during the second half of the 18th century, as recorded from Spanishlogbooks. A total of five sightings have been found, two corresponding toisolated bergs and three to outbreaks. The relevance of these results istwofold: they are the first documented iceberg sightings to date and, aboveall, they correspond to very unusual episodes, characterized by a high numberof high-sized bergs and by the relatively low latitude of their location. Itis suggested that they could be associated to cold episodes in Antarctica.  相似文献   

9.
Long-lasting community-based resource management systems have offered scholars important lessons in the study of human-environment relations. The examination of such systems has suffered from a sampling bias, however, in that it has focused disproportionately on successful systems. There are fewer studies that have explored the deterioration of such systems, particularly with an interdisciplinary approach. This shortfall is problematic given the increasing social and biophysical disturbances that communities are facing as they become more integrated into, and affected by, larger-scale processes.This study addresses this gap by analyzing the modern condition of a long-lasting community-based irrigation system known as the acequias in northern New Mexico. Using a mix of interview, survey, remote sensing, and census data, I examine the extent to which important indicators for the acequias have shifted in the last several decades and explore reasons for these changes. A mix of statistical and qualitative comparative techniques is used to conduct the analysis.By examining longitudinal data we find that the acequias are producing less than they have in the past and have mostly lost their common-property-based livestock pasturing system. While some of these changes can be attributed to similar declines in water availability, much of the change results from social drivers including demographic changes, regional-to-global market forces, and public policies. Overall the shift of the acequias to their current state is a result of their integration into a much larger-scale set of social and economic forces than they have experienced in the past. This shift will be very difficult to reverse, meaning the acequia farmers must adapt to the current condition. It is likely that these themes are common across many community-based resource management systems in many locations. In the future, further progress should be made in synthetically comparing such cases in ways that have already been done for long-lasting successful systems.  相似文献   

10.
Climatic variations in the range of 10 to 100 years duration are perhaps of greatest consequence to mankind because; (1) they have a tendency to be regional in nature, (2) they affect third-world countries as well as more developed countries, and (3) they prevail over the planning horizons used in water resources, agriculture and many other disciplines. Documentation of the range of variability experienced regionally for various regions in the western United States as well as North Africa are examined. The recent high water-levels of the Great Salt Lake and other lakes in the Western United States and the prolonged recent drought in North Africa are examples discussed in detail.  相似文献   

11.
We take issue with the claim by Tavoni and Tol (Clim Chang 100:769–778, 2010) that reviews of the macroeconomic costs of achieving the 2 °C climate target have been affected by selection bias and have underestimated the costs. Although many more cost estimates are available in the literature, they have restricted their survey to the data in the EMF22 study, with a limited set of model solutions for the 2 °C target. They have applied the methodology of observational meta-analysis inappropriately to policy meta-analysis, where the number of results is often very small and the basis for imputing a statistical distribution does not usually exist. They have mixed direct costs with net costs in terms of %GDP. Their method of “correcting” for missing data with (high) costs of stringent mitigation could equally be applied to correcting the data for omission of mitigation options such as biomass energy with carbon capture so reducing the cost estimates. And finally they implicitly assume that the same policy combinations and mitigation options are applied for all climate scenarios, when more stringent scenarios may require more stringent policies and options, such as regulation or BECCS. The conclusion from the literature is more appropriately that the costs are highly uncertain, that they can equally be positive or negative (gains) and that models which fail to solve for stringent mitigations are not fit for purpose.  相似文献   

12.
Chen  Hui  Wu  Wei  Liu  Hong-Bin 《Theoretical and Applied Climatology》2018,132(1-2):587-597
Theoretical and Applied Climatology - Numerous drought indices have been developed to analyze and monitor drought condition, but they are region specific and limited by various climatic conditions....  相似文献   

13.
温室气体的源与汇   总被引:40,自引:5,他引:35  
介绍了温室效应和温室气体的概念,阐述了当前6种主要温室气体(CO2、CH4、N2O、HFCsPFCs、SF6)及其源和汇。尽管目前后3种气体特别是PFCs和SF6在大气中的浓度很低,但它们有很高的增温潜势,在大气中寿命相当长,来自人类活动的排放必将造成它们在大气中不可逆的增长需要引起足够的重视。  相似文献   

14.
Estimates and predictions of people displaced by environmental changes have been highly instrumental in the ever-increasing attention given to environmental migration in the media. Yet no consensual estimate exists, let alone a commonly agreed methodology. As a result, predictions and estimates have become one of the most contentious issues in the debates on environmental migration. This article seeks to review the key estimates and predictions existing in the literature, as well as the methodologies they are built on, and the problems and caveats they are fraught with. The first part reviews the figures related to current estimates of people displaced by environmental changes, while a second part examines the predictions for future displacements. The next section synthesises the key methodological difficulties and a final section suggests some possible avenues for improvement.  相似文献   

15.
On 16 March 2004, we received an appeal from Dr. Qing WANG of the United States' Naval Postgraduate School questioning the legitimacy of the paper entitled, Modeling Marine Stratocumulus with a Detailed Microphysical Scheme, that was published by ZHAO Chunsheng and Yutaka Ishizaka in the January 2004 issue of the Advances in Atmospheric Sciences (AAS). She pointed out that the model described in the paper was developed by her group in which the first author, Dr. Zhao, worked as a visiting scholar during February 1997-February 1998. The authors should not have claimed in the paper that they developed the model. In particular, they should not have published her group's work as their own. Thus, Dr. Wang requested that the paper be retracted from AAS.  相似文献   

16.
17.
MJO与ENSO关系的研究进展   总被引:1,自引:0,他引:1  
MJO是热带大气的强信号,ENSO是热带太平洋海气相互作用的最强信号,两者的时间空间尺度不同,但都对全球范围的大气活动有显著的影响,且两者之间也有着密切的关系。总结了近年来MJO和ENSO相互关系方面的研究,并在此基础上提出需要进一步研究的问题。  相似文献   

18.
广东致洪特大暴雨的综合分析   总被引:6,自引:1,他引:5  
对广东1949年至1994年发生的12场造成较大洪涝灾害的特大暴雨进行分析,发现广东的致洪特大暴雨基本上可以分为3类,并具有不同的环流和物理量特征:西北江并发洪水的特大暴雨一般发生在前汛期,暴雨持续时间长、范围广、灾情重,暴雨期间环流稳定,锋面降雨系统完整,暴雨层结不稳定面积大;沿海诸河及小支流洪水致洪暴雨多发生在后汛期,暴雨突发性强、持续时间短、雨强大,暴雨主要是由于热带气旋的入侵而造成,只在暴雨区附近有明显的层结不稳定,对流现象非常强烈;造成东江及其它主要支流洪水的暴雨则可能是锋面雨也可能是热带气旋雨,稳定度指数及分布状况介于二者之间。  相似文献   

19.
Theorizations of sustainability transformation have foregrounded the construction (making) of novel socioecological relations; however, they generally have obscured processes of deliberate deconstruction (unmaking) of existing, unsustainable ones. Amidst ever more compelling evidence of the simultaneous unsustainability and continued reproduction of capitalist modernity, it is misguided to assume that transformation can happen by the mere construction of supposed ‘solutions’, be they technological, social or cultural. We rather need to better understand whether and how existing institutions, forms of knowledge, practices, imaginaries, power structures, and human-non-human relations can be deconstructed at the service of sustainability transformation. This paper demonstrates the usefulness of a lens that attends to processes of making and unmaking in sustainability transformations through an analysis of an ongoing sustainability transformation, the territorios campesinos agroalimentarios (TCA) endogenous territorial figure and peasant movement in Colombia. TCA is transforming territory beyond capitalism on the basis of relational ontologies and principles of autonomy, dignity and sufficiency. This paper identifies processes of unmaking of capitalism in the TCA and demonstrates how they are concretely entangled in the construction of post-capitalist realities. This paper sketches a research agenda on sustainability transformation that is sensitive to and theoretically equipped for the analysis of transformation as a multifaceted, multilevel process that entails the deconstruction of capitalist modernity and the construction of post-capitalist realities. Central to this agenda is a plural engagement with theories of social change from across the social sciences and humanities, which have not previously been mobilized for this endeavour.  相似文献   

20.
Why have carbon markets been rapidly adopted as policy solutions to climate change in the last decade? Perhaps surprisingly, this question has attracted virtually no attention in the large literature on such markets. The standard arguments given for why carbon markets are good ways to respond to climate change do not explain why such markets have flourished as governance mechanisms in relation to climate. Carbon markets have spread and become taken-for-granted because of the potential they give to certain powerful actors (financiers, specifically) to create new cycles of investment, profits and growth. As a consequence, they make possible a political coalition combining financiers with environmentalists. This coalition has considerable potential to legitimize substantial cuts in carbon emissions in the face of continued opposition from other interests. It is the combination of these two elements – the promotion of specific growth sectors and the construction of a political coalition – that constitutes the principal political virtue of carbon markets. In order to demonstrate this claim, the history of emissions trading is traced and the implication of this analysis is explored for the further building of climate governance centred on carbon markets.  相似文献   

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