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1.
The critical comments to the publications by the authors ofthe present paper that were given in [10] (the publications deal with the possible effects of gravity field inhomogeneities in the atmosphere and ocean) are discussed. In the authors' opinion, some remarks are groundless. At the same time, the authors agree with one of the important remarks that the results of their paper concerning studies of the ocean disturbances are to be reconsidered.  相似文献   

2.
We appreciate many of Zhang's critical comments and constructive recommendations(Zhang 2002) for the reform of Advances in Atmospheric Sciences (AAS). An annualAAS Editorial Board meeting was held on 19 December 2001 at the Institute of AtmosphericPhysics (IAP) of Chinese Academy of Sciences. Zhang's letter (Zhang 2002) was distributed to  相似文献   

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Climate adaptation is not a neutral or apolitical process, but one that ignites social resistance. Government responses to risks of floods, droughts, or hurricanes – even those using a language of participation – might follow historical development pathways, strive to maintain the status quo, and directly or indirectly serve elite interests. Little attention has been paid to how people defy or resist top-down adaptation processes, overtly or covertly, in particular cultural, historical, and legal contexts. Drawing on sociological thought on popular resistance, this paper systematises research on people’s resistance to climate adaptation by scrutinising the sites, repertoires, and consequences of such resistance. We identified overt and covert resistance in 56 scientific adaptation articles, which concentrated on 5 ‘sites’ of resistance: Rural livelihoods, Urban informal settlements, Islands, First Nations, and Institutional landscapes. The findings imply that resistance to adaptation occurs globally, and not least in the context of relocation processes and participatory adaptation. We show how a resistance lens can help understand contemporary political behaviours, shed light on dynamic and compound vulnerability, and’unlock’ more context-sensitive and even transformative adaptation. Meanwhile, resistance and popular movements are not only progressive, and there might be conceptual barriers to moving from resistance to transformation or reconciling resistance with actions by or with the state.  相似文献   

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This case study investigates a stratospheric intrusion event down to the earth’s surface (near sea-level pressure) of the greater area of Athens (23.43°E 37.58°N), which occurred on 9 October 2003 and caused a remarkable increase in surface ozone concentrations not related to photochemical production. This event is among the rare case studies investigating, on the one hand, a deep stratospheric intrusion down to the earth’s surface at near sea-level pressure and, on the other, an event affecting the near surface ozone of a megacity such as Athens. The synoptic situation is described by a deep upper lever trough at 300 and 500 hPa extending over Greece, which is related to a deep tropopause fold as revealed by vertical cross sections of potential vorticity, relative humidity, divergence and vertical velocity. The analysis of potential vorticity at several isentropic levels indicates a hook-shaped streamer of high PV values (greater than 4 pvu at the 315 K isentropic level) over southeast Europe, which coincides with a streamer of dry air as observed from satellite images of water vapor. The aforementioned structure characterizes a textbook case study of stratosphere-to-troposphere transport. The Lagrangian particle dispersion model FLEXPART was used to calculate the trajectories of air particles reaching the receptor site and the fraction of particles with stratospheric origin. It reveals an important direct stratospheric impact within 1 day related to the tropopause fold described in this study with the fraction of stratospheric particles reaching maximum values of 1.9 and 4.5% for threshold values of the dynamical tropopause 2 and 1.5 pvu, respectively. Furthermore, a larger indirect aged stratospheric contribution is also revealed 4 to 5 days prior to the release, related to stratospheric intrusion events at the western Atlantic Ocean, reaching maximum values of 2.5 and 6.9% of particles crossing the 2 and 1.5 pvu potential vorticity surfaces, respectively.  相似文献   

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The Aichi 2020 Targets, under the Convention on Biological Diversity (CBD), aim to halt the loss of biodiversity by 2020, in order to ensure that ecosystems continue to provide essential services. Here we apply a social–ecological systems analysis to provide insight into the diverse system interactions that pose impediments to delivery of the Aichi Targets. We applied an analytical framework of pair-wise exchanges along six axes between the social, economic, environmental and political loci of the global social–ecological system. The analysis identified that many impediments result from partial decoupling in the system through phenomena including delayed feedbacks and insufficient information flows. It suggests 15 of the Aichi Targets are unlikely to be delivered; 3 are likely to be delivered in part; and 2 in full. We considered how interventions at leverage points may overcome the impediments, and compared these to actions included within the Implementation Decision for the Aichi Targets, to find gaps. These new leverage points to fill identified gaps involve many aspects of system re-coupling: co-production of knowledge and more equitable food systems governance (environmental–social axis); support for social change movements (social–political axis); an appropriate financial target for biodiversity conservation investment, with a clear means of implementation such as a currency transaction tax (economic–political axis); and co-governance of natural resources (environmental–political axis). The recently released Global Biodiversity Outlook 4 shows that 18 of the 20 Aichi Targets are tracking in accordance with our analysis; and that current efforts are unlikely to result in an improvement in the base state of biodiversity by 2020, confirming some of our results. We argue that attention to the interactions within, and the partial decoupling of, the global social–ecological system provides new insights, and is worthy of further attention both for delivery of the Aichi Targets and for guiding longer term actions for the conservation of biodiversity.  相似文献   

8.
《大气与海洋》2013,51(4):283-299
Abstract

The Middle Atmosphere Nitrogen TRend Assessment (MANTRA) series of high‐altitude balloon flights is being undertaken to investigate changes in the concentrations of northern hemisphere mid‐latitude stratospheric ozone, and of nitrogen and chlorine compounds that play a role in ozone chemistry. Four campaigns have been carried out to date, all from Vanscoy, Saskatchewan, Canada (52°01'N, 107°02'W, 511.0 m). The first MANTRA mission took place in August 1998, with the balloon flight on 24 August 1998 being the first Canadian launch of a large high‐altitude balloon in about fifteen years. The balloon carried a payload of instruments to measure atmospheric composition, and made measurements from a float altitude of 32–38 km for one day. Three of these instruments had been flown on the Stratoprobe flights of the Atmospheric Environment Service (now the Meteorological Service of Canada) in the 1970s and early 1980s, providing a link to historical data predating the onset of mid‐latitude ozone loss.

The primary measurements obtained from the balloon‐borne instruments were vertical profiles of ozone, NO2, HNO3, HCl, CFC‐11, CFC‐12, N2O, CH4, temperature, and aerosol backscatter. Total column measurements of ozone, NO2, SO2, and aerosol optical depth were made by three ground‐based spectrometers deployed during the campaign. Regular ozonesonde and radiosonde launches were also conducted during the two weeks prior to the main launch in order to characterize the local atmospheric conditions (winds, pressure, temperature, humidity) in the vicinity of the primary balloon flight. The data have been compared with the Model for Evaluating oZONe Trends (MEZON) chemical transport model, the University of California at Irvine photochemical box model, and the Canadian Middle Atmosphere Model (CMAM) to test our current understanding of model photochemistry and mid‐latitude species correlations. This paper provides an overview of the MANTRA 1998 mission, and serves as an introduction to the accompanying papers in this issue of Atmosphere‐Ocean that describe specific aspects and results of this campaign.  相似文献   

9.
《大气与海洋》2013,51(2):85-100
Abstract

The sensitivity of the Canadian Regional Climate Model (CRCM), developed at the Université du Québec à Montréal, and the Gulf of St. Lawrence Ocean Model (GOM), developed at the Institut Maurice‐ Lamontagne, to each other is tested with an ensemble of simulations over eastern Canada from 1 November 1989 to 31 March 1990. The goal of this study is to investigate the interaction of the CRCM and GOM with respect to each other's forcing fields. In the first part of the experiment, a series of simulations were performed using an iterative strategy, where both models run separately and alternately, using variables from the other model to supply the needed forcing fields for the computation of surface fluxes. The runs are iterated several times over the same period from the output of the previous run to allow the atmosphere and the ocean to interact several times with each other and to study the evolution of the solutions from one iteration to the next. In the second part of the experiment, a two‐way coupled simulation is performed over the same period. The results indicate that on a monthly or longer timescale, the CRCM is not very sensitive to the details of the oceanic fields from GOM, except locally over the Gulf of St. Lawrence (GSL). However, GOM is quite sensitive to the differences in atmospheric fields from the CRCM. The results of several iterations converge to a unique solution, suggesting that the CRCM and GOM reach equilibrium with respect to each other's forcing fields. Furthermore, the results of the coupled run also converge to this same solution.  相似文献   

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The problem of the contribution of cosmic rays to climate change is a continuing one and one of importance. In principle, at least, the recent results from the CLOUD project at CERN provide information about the role of ionizing particles in ’sensitizing’ atmospheric aerosols which might, later, give rise to cloud droplets. Our analysis shows that, although important in cloud physics the results do not lead to the conclusion that cosmic rays affect atmospheric clouds significantly, at least if H2SO4 is the dominant source of aerosols in the atmosphere. An analysis of the very recent studies of stratospheric aerosol changes following a giant solar energetic particles event shows a similar negligible effect. Recent measurements of the cosmic ray intensity show that a former decrease with time has been reversed. Thus, even if cosmic rays enhanced cloud production, there would be a small global cooling, not warming.  相似文献   

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将边界层相似性理论同线性热力学理论结合,间接地以观测实验事实证明大气边界层内线性唯象关系是成立的,而且线性湍流输送系数同相应的线性唯象系数成正比关系。但实验事实表明,大涡对流的混合层线性唯象系数成正比关系。但实验事实表明,大涡对流的混合层线性唯象关系是不成立的,混合层内湍流输送过程是一种强的非线性过程。所以,对流边界层是一种远离平衡态非线性区的热力学状态。地转风和热成风是一种大气系统特有的动力过程和热力过程和交叉耦合现象,这是大气系统交叉耦合现象的一个实际例证。  相似文献   

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1. IntroductionRecently, the improvement of accuracy in the out-puts of a numerical mesoscale model by the physi-cal dissipative technique is reached (Liu et al., 2002;Liu and Liu, 2003). The effect of improvement ofthis technique differs not only from model to model,but from scheme to scheme of parameterization em-ployed in the same model. The rapid developmentof the computer technology makes possible the com-plicated numerical experiments by a model with highresolution and multiple domains …  相似文献   

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从一般的热力学原理或其它自然原理对唯象关系所强加的限制,能够演绎出大气系统的一系列热力学性质。利用非平衡态线性热力学导出了湍流K闭合理论中湍流交换系数同唯象系数的关系,从理论上证明大气系统热量湍流输送同水泡之间存在交叉耦合,还导出了湍流强度同速度和位温梯度的关系,从而证明速度和位温空间分布的非均匀性是湍流之源。并证明湍流强度定理,不可压缩气体和各向同性湍流大气中,湍流强度正比于速度与位温梯度的标积。进而证明大气涡旋定理,位温的切变将导致涡旋运动或各种环流运动,速度涡度等于速度同位温相对梯度的矢积。展现了线性热力学在大气系统的应用前景。  相似文献   

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Abstract

A model to compute rapidly the absorption of solar radiation in the atmosphere is described. The model is based partially on the parameterization of Lacis and Hansen and also makes use of the delta‐Eddington method. In addition to absorption by ozone and water vapour, and scattering by air molecules and clouds, the mode1 includes absorption and scattering by aerosols. Good agreement is found in comparison with the Lacis and Hansen parameterization in the absence of clouds and aerosol. The present model represents an improvement in the treatment of scattering by clouds. Its main advantage though, is in its flexibility in allowing for interactions with the atmospheric aerosol.  相似文献   

18.
This paper asks whether extreme weather events are becoming more discernible. It uses the Vanderbilt University Television News Archives to determine if annual coverage given to heat waves, droughts, hurricanes and floods has increased on the network news between 1968 and 1996. An index of extreme weather events shows a clear trend toward increased coverage, especially since 1988. However, the different types of extreme events do not receive equal coverage: for example, annual peaks for droughts contain about twice as many stories as the peaks for heat waves. The data further reveal that there is no association between coverage of climate change and the overall coverage of extreme events. While extreme events have attracted more stories in the U.S., there has been no increase in the coverage devoted to extreme events in foreign countries. The possible effects of shifts in TV coverage on the public salience and understanding of climate change are discussed.  相似文献   

19.
The mechanism of the locking of the E1 Nino event onset phase to boreal spring (from April to June) in an intermediate coupled ocean-atmosphere model is investigated. The results show that the seasonal variation of the zonal wind anomaly over the equatorial Pacific associated with the seasonal variation of the ITCZ is the mechanism of the locking in the model. From January to March of the E1 Nino year, the western wind anomaly over the western equatorial Pacific can excite the downwelling Kelvin wave that propagates eastward to the eastern and middle Pacific by April to June. From April to December of the year before the E1 Nifio year, the eastern wind anomaly over the equatorial Pacific forces the downwelling Rossby waves that modulate the ENSO cycle. The modulation and the reflection at the western boundary modulate the time of the transition from the cool to the warm phase to September of the year before the E1 Nifio year and cause the strongest downwelling Kelvin wave from the reflected Rossby waves at the western boundary to arrive in the middle and eastern equatorial Pacific by April to June of the E1 Nino year. The superposition of these two kinds of downwelling Kelvin waves causes the El Nino event to tend to occur from April to June.  相似文献   

20.
Chen  Mengyan  Chang  Ting-Huai  Lee  Ching-Teng  Fang  Shih-Wei  Yu  Jin-Yi 《Climate Dynamics》2021,56(1-2):581-595
Climate Dynamics - This study examines a climate model hindcast of the responses of the western Pacific subtropical high (WPSH) to three types of El Niño events: the Eastern Pacific (EP) El...  相似文献   

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