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1.
Summary The sign of the vector representing the atmospheric electric field has recently been subject of debate. For the sake of clarity, it is recommended to refer only to a normal or reversed clear-weather potential gradient.
Zusammenfassung Eine in letzter Zeit entstandene Diskussion darüber, welches Vorzeichen dem Vektor des atmosphärisch-elektrischen Feldes bzw. des Potentialgefälles zuerkannt werden soll, erscheint wenig sinnvoll. Zur Vermeidung künftiger Unklarheiten wird empfohlen, bei der atmosphärischen Elektrizität nur von normaler Schönwetterrichtung und umgekehrter Schönwetterrichtung des Feldes bzw. des Potentialgefälles zu sprechen.

Résumé Une récente discussion a porté sur le signe qui devait être attribué au vecteur du champ électrique atmosphérique respectivement de son gradient de potentiel. On recommande, pour éviter à l'avenir toute confusion, de ne parler en électricité atmosphérique et quand il s'agit du champ ou du gradient de potentiel, que de «direction normale de beau temps» et de «direction inversée de beau temps».


Dedicated to Dr.W. Mörikofer on the occasion of his 70th birthday.  相似文献   

2.
《Climate Policy》2013,13(4):387-393
Abstract

Russia has a crucial veto on the entry into force of the Kyoto Protocol. The preparation of the ratification and institutional reform have begun in April 2002. The ratification process is based on the activities by high-level policy makers who have other priorities, federal level institutional actors which may be unclear about their roles and the few overloaded expert civil servants. After the US withdrawal from Kyoto, arguments against ratification have appeared in the Russian debate, mostly based on the lack of clarity of the economic benefits available. Ratification would require Russia to establish an eligibility strategy under Kyoto and divide responsibilities and rights between the government, regional and private sector actors. The legal procedure of ratification is simple but internal political complexities may delay the process.  相似文献   

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《Climate Policy》2002,2(4):387-393
Russia has a crucial veto on the entry into force of the Kyoto Protocol. The preparation of the ratification and institutional reform have begun in April 2002. The ratification process is based on the activities by high-level policy makers who have other priorities, federal level institutional actors which may be unclear about their roles and the few overloaded expert civil servants. After the US withdrawal from Kyoto, arguments against ratification have appeared in the Russian debate, mostly based on the lack of clarity of the economic benefits available. Ratification would require Russia to establish an eligibility strategy under Kyoto and divide responsibilities and rights between the government, regional and private sector actors. The legal procedure of ratification is simple but internal political complexities may delay the process.  相似文献   

5.
Based on experiments using a coupled general circulation model which resolves tropical ocean–atmosphere coupled phenomena such as El Niño/Southern Oscillation (ENSO) and the Indian Ocean Dipole, forcing mechanisms of the Indian Ocean subtropical dipole (IOSD) are investigated. In the control experiment, as in the observation, several types of the IOSD are generated by the variations in the Mascarene High during austral summer and characterized by a dipole pattern of sea surface temperature (SST) anomalies in the northeastern and southwestern parts of the southern Indian Ocean. In another experiment, where the SST outside the southern Indian Ocean is nudged toward the monthly climatology of the simulated SST, one type of the IOSD occurs, but it is less frequent and associated with the zonal wavenumber four pattern of equivalently barotropic geopotential height anomalies in high latitudes, suggesting an interesting link with the Antarctic Circumpolar Wave. This indicates that, even without the atmospheric teleconnection from tropical coupled climate modes, the IOSD may develop in association with the atmospheric variability in high latitudes of the Southern Hemisphere. In the other experiment, where only the southern Indian Ocean and the tropical Pacific are freely interactive with the atmosphere, two types of both positive and negative IOSD occur. Since the occurrence frequency of the IOSD significantly increases as compared to the second experiment, this result confirms that the atmospheric teleconnection from ocean-atmosphere coupled modes in the tropical Pacific such as ENSO may also induce the variations in the Mascarene High that generate the IOSD. The present research, even within the realm of model studies, shows clearly that the predictability of the IOSD in mid-latitudes is related to both low and high-latitudes climate variations.  相似文献   

6.
The retrospective forecast skill of three coupled climate models (NCEP CFS, GFDL CM2.1, and CAWCR POAMA 1.5) and their multi-model ensemble (MME) is evaluated, focusing on the Northern Hemisphere (NH) summer upper-tropospheric circulation along with surface temperature and precipitation for the 25-year period of 1981–2005. The seasonal prediction skill for the NH 200-hPa geopotential height basically comes from the coupled models’ ability in predicting the first two empirical orthogonal function (EOF) modes of interannual variability, because the models cannot replicate the residual higher modes. The first two leading EOF modes of the summer 200-hPa circulation account for about 84% (35.4%) of the total variability over the NH tropics (extratropics) and offer a hint of realizable potential predictability. The MME is able to predict both spatial and temporal characteristics of the first EOF mode (EOF1) even at a 5-month lead (January initial condition) with a pattern correlation coefficient (PCC) skill of 0.96 and a temporal correlation coefficient (TCC) skill of 0.62. This long-lead predictability of the EOF1 comes mainly from the prolonged impacts of El Niño-Southern Oscillation (ENSO) as the EOF1 tends to occur during the summer after the mature phase of ENSO. The second EOF mode (EOF2), on the other hand, is related to the developing ENSO and also the interdecadal variability of the sea surface temperature over the North Pacific and North Atlantic Ocean. The MME also captures the EOF2 at a 5-month lead with a PCC skill of 0.87 and a TCC skill of 0.67, but these skills are mainly obtained from the zonally symmetric component of the EOF2, not the prominent wavelike structure, the so-called circumglobal teleconnection (CGT) pattern. In both observation and the 1-month lead MME prediction, the first two leading modes are accompanied by significant rainfall and surface air temperature anomalies in the continental regions of the NH extratropics. The MME’s success in predicting the EOF1 (EOF2) is likely to lead to a better prediction of JJA precipitation anomalies over East Asia and the North Pacific (central and southern Europe and western North America).  相似文献   

7.
This paper examines the robustness of the long-run, cointegrating, relationship between global temperatures and radiative forcing. It is found that the temperature sensitivity to a doubling of radiative forcing is of the order of 2 ± 1°C. This result is robust across the sample period of 1850 to 2000, thus providing further confirmation of the quantitative impact of radiative forcing and, in particular, CO2 forcing, on temperatures.  相似文献   

8.
We investigated the potential of the new generation of satellite precipitation product from the Global Precipitation Mission (GPM) to characterize the rainfall in Malaysia. Most satellite precipitation products have limited ability to precisely characterize the high dynamic rainfall variation that occurred at both time and scale in this humid tropical region due to the coarse grid size to meet the physical condition of the smaller land size, sub-continent and islands. Prior to the status quo, an improved satellite precipitation was required to accurately measure the rainfall and its distribution. Subsequently, the newly released of GPM precipitation product at half-hourly and 0.1° resolution served an opportunity to anticipate the aforementioned conflict. Nevertheless, related evidence was not found and therefore, this study made an initiative to fill the gap. A total of 843 rain gauges over east (Borneo) and west Malaysia (Peninsular) were used to evaluate the rainfall the GPM rainfall data. The assessment covered all critical rainy seasons which associated with Asian Monsoon including northeast (Nov. - Feb.), southwest (May - Aug.) and their subsequent inter-monsoon period (Mar. - Apr. & Sep. - Oct.). The ability of GPM to provide quantitative rainfall estimates and qualitative spatial rainfall patterns were analysed. Our results showed that the GPM had good capacity to depict the spatial rainfall patterns in less heterogeneous rainfall patterns (Spearman’s correlation, 0.591 to 0.891) compared to the clustered one (r = 0.368 to 0.721). Rainfall intensity and spatial heterogeneity that is largely driven by seasonal monsoon has significant influence on GPM ability to resolve local rainfall patterns. In quantitative rainfall estimation, large errors can be primarily associated with the rainfall intensity increment. 77% of the error variation can be explained through rainfall intensity particularly the high intensity (> 35 mm d-1). A strong relationship between GPM rainfall and error was found from heavy (~35 mm d-1) to violent rain (160 mm d-1). The output of this study provides reference regarding the performance of GPM data for respective hydrology studies in this region.  相似文献   

9.
A nested numerical model system has been set up to realistically simulate more than 30 years of the Indonesian throughflow (ITF). A global circulation model delivered the boundary values for sea level, temperature and salinity distributions to a local model covering the region of the ITF. Both models were forced with NCEP data. Results of the regional model are in good agreement with measured data regarding velocity distribution and stratification, as well as transported water masses. Model results show a highly variable and very complex current system. The presence of a realistic throughflow has been simulated even with a barotropic pressure gradient directed from the Indian towards the Pacific Ocean. Furthermore, model experiences indicate that the intensity of the ITF is correlated with the seasonal wind system. It is concluded that the ITF is neither driven by a barotropic or baroclinic pressure gradient nor by local winds. The ITF seems to be, rather, the extension of the very strong tropical Pacific Ocean circulation system westward into the Indonesian seas, where the western boundary is not fully closed due to the passages between the Indonesian islands. A hypothesis for the physical reason is given to explain the existence of the Indonesian throughflow.  相似文献   

10.
The climate negotiations recognize that adequate and additional funds are needed to assist adaptation in developing countries. This article analyses whether a future 2% or any higher adaptation levy (AL) can achieve this, whether it causes – as it is a tax on the Clean Development Mechanism (CDM) – a significant excess burden, and how it alters the relation between adaptation financing and mitigation. While former studies have focused on single AL levels, this article determines the transfers from the CDM and the AL for a range of emission reduction targets and AL levels with a partial equilibrium model based on marginal abatement cost estimates for 2020. Revenues from a 2% AL are negligible and remain inadequate for ambitious emission reductions and an AL that maximizes transfers (e.g. US$15 billion for 30% reduction target). Revenues are mostly subtracted from CDM transfers, so little additional funds are raised (e.g. less than $2.4 billion for 30% reduction target). Adaptation financing increases disproportionally with more stringent reduction targets for a rising levy, and the share of Annex I country expenditures devoted to transfers increases slightly. Both effects are only small. The excess burden is larger than 85% of the additional funds.

Policy relevance

Financing adaptation in developing countries has become a cornerstone of a global climate agreement. The mechanism for raising additional funds has not yet been determined. This article assesses the potential of upscaling one option that is already in place under the Kyoto Protocol: the 2% AL on the CDM. It is estimated that even a much higher AL does not generate substantial additional funds, mainly redistributes transfers within non-Annex I countries, does so at social costs in the same order of magnitude as additional funds, and increases the share of Annex I country expenditures devoted to transfers. It is unwise to link mitigation and adaptation as CDM and AL jointly do, since this taxes a beneficial activity. Financial instruments with transfers that decrease with or are independent from climate protection would be preferable.  相似文献   

11.
The United Nations’ Sustainable Development Goals (SDGs) are described as integrated and indivisible, where sustainability challenges must be addressed across sectors and scales to achieve global-level sustainability. However, SDG monitoring mostly focuses on tracking progress at national-levels, for each goal individually. This approach ignores local and cross-border impacts of national policies and assumes that global-level progress is the sum of national, sector-specific gains. In this study, we investigate effects of reforestation programs in China on countries supplying forest and agricultural commodities to China. Using case studies of rubber and palm oil production in Southeast Asian countries, soy production in Brazil and logging in South Pacific Island states, we investigate cross-sector effects of production for and trade to China in these exporting countries. We use a three-step multi-method approach. 1) We identify distal trade flows and the narratives used to justify them, using a telecoupling framework; 2) we design causal loop diagrams to analyse social-ecological processes of change in our case studies driven by trade to China and 3) we link these processes of change to the SDG framework. We find that sustainability progress in China from reforestation is cancelled out by the deforestation and cross-sectoral impacts supporting this reforestation abroad. Narratives of economic development support commodity production abroad through unrealised aims of benefit distribution and assumptions of substitutability of socio-ecological forest systems. Across cases, we find the analysed trade supports unambiguous progress on few SDGs only, and we find many mixed effects – where processes that support the achievement of SDGs exist, but are overshadowed by counterproductive processes. Our study represents a useful approach for tracking global-level impacts of national sustainability initiatives and provides cross-scale and cross-sectoral lenses through which to identify drivers of unsustainability that can be addressed in the design of effective sustainability policies.  相似文献   

12.
In July, heating of the continents in the Northern Hemisphere results in strengthened monsoon systems which bring rains to West Africa. In Nigeria, the annual rainfall total decreases from over 3,800 mm at Forcados on the coast to under 650 mm at Maiduguri in the north-east of the country. June, July, August and September are the rainiest months throughout the country. In many parts of the south, however, there is “supposed to be” a slight break in the rains for some 2 to 3 weeks in late July and early August or the so called “August break”. In this study, we are underscoring the obvious that climate is changing. The daily series of rainfall data for 1983–2003 analyzed between the months of July–August for some sites in the Eastern humid zone of Southern Nigeria shows that the “August break” may indeed “be breaking”. We have discussed some practical approaches to climate change research in this monsoon region.  相似文献   

13.
Along with the large middle-income countries Brazil, China, and South Africa, India has been put under increasing pressure to shoulder parts of the mitigation burden and commit to national emission reduction targets. India, however, refers to its limited capacity and widespread poverty. Is India hiding behind its poor? While others examine the distribution of emissions within the country to answer this question, we study domestic policy making for energy subsidies and access to clean energy. Empirical evidence suggests that domestic policy making is at least partially consistent with the pro-poor arguments advanced at the international level. Given their large number and the country's democratic system, the poor do have some weight in Indian politics. However, pro-poor policies end where they do not translate into greater vote shares. Moreover, India's international position ignores the existing complementarities between climate-friendly and pro-poor activities.

Policy relevance

Despite India's recent growth spurt, its concern to fight energy poverty at home before engaging in any commitments on climate policy at the international level should be taken seriously within the international negotiations. Policy making in India is driven by democratic incentives, which, in this case, work to the benefit of the poor. Pro-poor policies may not go as far as one would wish from a developmental perspective, but the impact of the masses of the poor on domestic policy making is politically significant and cannot be ignored. This also provides some broader lessons for mitigation and adaptation policies in developing countries: politicians respond to incentives and support will only reach the needy if the appropriate incentives are in place. While we observe some significant commitment and implementation problems even in a democratic country like India, such problems must be expected to be even more serious elsewhere. This should not be overlooked when designing institutions for the allocation of climate finance, such as the Green Climate Fund.  相似文献   

14.
Sublimation and melt disturb the environmental information obtained from ice core records in the Andes. In two case studies we demonstrate to what extent these post-depositional processes may remove major parts of the accumulated snow cover. Dark ash layers from the Tungurahua eruption changed the albedo of surface snow on Chimborazo glacier (6268 m, 1°30 S,78°36 W, Ecuador) between two ice core drilling campaigns and forced substantial melt. Re-distribution and washout of the chemical constituents shifted the concentration profiles obtained in December 1999 as compared to an equivalent core drilled in December 2000. The stable isotope records showed that approximately the water equivalent (weq) of an annual layer had melted, and that the percolating melt water penetrated within the firn layer to a depth of at least 16.5 m without refreezing. In the second example, from a site on the dry axis between the tropical and extra-tropical precipitation belts, significant loss of accumulated snow layers occurred by sublimation. A surface experiment at Cerro Tapado glacier (5536 m, 30°08 S,69°55 W, Chile) revealed that losses of 2 mm weq (5 mm snow) per day occurred during the dry period following the 1997/98 El Niño. This loss generally included the entire surface layer enriched in stable isotopes, and thus caused minimal disturbance of the isotopic signature (and hence climatic information) of the net accumulation, yet chemical constituents again experienced considerable changes in concentration. From annual layer counting and direct dating it is obvious that the major part of the accumulated ice on both glaciers is younger than 100 years; however, isotopic and chemical variations at least in the basal ice from Cerro Tapado clearly point to climate conditions different from the recent centuries. This evidence is supported by mass balance considerations derived from a glacier-climate model. The possibility of a third type of disturbance aside from sublimation and melting – in this case a significant hiatus in the environmental chronology – also deserves consideration for other icecore records from this region. Potential disruptions or discontinuities need to be carefully evaluated given the profound changes in climatic and glaciological conditions since the Last Glacial Maximum throughout Holocene times.  相似文献   

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Subjective approaches to resilience measurement are gaining traction as a complementary approach to the standard frameworks that typically contain objective measures. Proponents suggest that subjective approaches may add value to existing measures in three areas: by improving our understanding of the drivers of resilience, reducing the questionnaire burden on respondents, and potentially offering more valid cross-cultural comparisons. This perspective assesses the potential, evidence and uncertainties around each of these claims, drawing from decades of research using subjective techniques in the wellbeing and psychological resilience literatures. Overall we find that subjective approaches can theoretically add value in each of these three areas. However the design of appropriate indicators must proceed with specificity and rigour for subjective measures to add value to programming and policy for climate resilience.  相似文献   

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Metrics are often used to compare the climate impacts of emissions from various sources, sectors or nations. These are usually based on global-mean input, and so there is the potential that important information on smaller scales is lost. Assuming a non-linear dependence of the climate impact on local surface temperature change, we explore the loss of information about regional variability that results from using global-mean input in the specific case of heterogeneous changes in ozone, methane and aerosol concentrations resulting from emissions from road traffic, aviation and shipping. Results from equilibrium simulations with two general circulation models are used. An alternative metric for capturing the regional climate impacts is investigated. We find that the application of a metric that is first calculated locally and then averaged globally captures a more complete and informative signal of climate impact than one that uses global-mean input. The loss of information when heterogeneity is ignored is largest in the case of aviation. Further investigation of the spatial distribution of temperature change indicates that although the pattern of temperature response does not closely match the pattern of the forcing, the forcing pattern still influences the response pattern on a hemispheric scale. When the short-lived transport forcing is superimposed on present-day anthropogenic CO2 forcing, the heterogeneity in the temperature response to CO2 dominates. This suggests that the importance of including regional climate impacts in global metrics depends on whether small sectors are considered in isolation or as part of the overall climate change.  相似文献   

19.
Carbon emissions—and hence fossil fuel combustion—must decline rapidly if warming is to be held below 1.5 or 2 °C. Yet fossil fuels are so deeply entrenched in the broader economy that a rapid transition poses the challenge of significant transitional disruption. Fossil fuels must be phased out even as access to energy services for basic needs and for economic development expands, particularly in developing countries. Nations, communities, and workers that are economically dependent on fossil fuel extraction will need to find a new foundation for livelihoods and revenue. These challenges are surmountable. In principle, societies could undertake a decarbonization transition in which they anticipate the transitional disruption, and cooperate and contribute fairly to minimize and alleviate it. Indeed, if societies do not work to avoid that disruption, a decarbonization transition may not be possible at all. Too many people may conclude they will suffer undue hardship, and thus undermine the political consensus required to undertake an ambitious transition. The principles and framework laid out here are offered as a contribution to understanding the nature of the potential impacts of a transition, principles for equitably sharing the costs of avoiding them, and guidance for prioritizing which fossil resources can still be extracted.  相似文献   

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