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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   

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Clean and affordable energy is crucial to achieve a sustainable future. Despite being controversial, hydropower remains the predominant low-cost and reliable source of energy at global level, as it stabilizes the provision of electricity and it bears the power peaks without losing efficiency. However, hydropower requires huge upfront investments and patient functional capital. Under the Paris Agreement, countries committed to direct financial capital flows towards a low-emission pathway in order to enable the transition. Furthermore, private capital strongly engaged with a transition towards a climate-smart economy. The aim of this work is to study the investment system behind hydropower, investors’ behaviour and the optimal allocation of finance to favour the deployment of capital flows. We use Bloomberg Energy Finance database to track public–private investments over the past century (1903–2020). We use network models to represent the hydropower project financing landscape as a network of co-investments. We find that investors are highly localized, with continental players mostly interacting with counterparts in the same area of the world. Powerful exceptions are international organisations and multilateral banks which coinvest across the globe. They also tend to support low-income and fragile countries, meeting their mandate of sustainable development champions. Multilateral banks and international organisations are the most critical actors in enabling public–private co-investments; they activate partnerships with a wider diversity of investors within the network creating more opportunities for blended finance tools. Our results offer a novel perspective on finance for the energy transition: it challenges the idea that more capital invested is better and calls for a more efficient allocation of the available resources.  相似文献   

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The highly visible coastal phenomenon of wetland loss in coastal Louisiana (LA) was examined through the prism of carbon accumulation and loss. Carbon storage or sequestration in rapidly subsiding LA coastal marsh soils was based on vertical marsh accretion and aerial change data. Marshes sequester significant amount of carbon through vertical accretion however, large amounts of carbon previously sequestration in the soil profile is lost through annual deterioration of these coastal marshes. Hurricanes, such as Katrina and Rita, have triggered instantaneous large carbon losses of sequestered soil carbon through the destruction of large areas of marsh. This analysis shows proposed coastal restoration efforts will not be sufficient to restore carbon losses by storms and marsh deterioration. Further, we have estimated the economic benefit of carbon sequestration for coastal wetland restoration efforts. Results show that LA coastal marshes may not serve as a net sink of carbon. These results may serve as a predictor of the impact of future predictions of increasing global sea level rise on carbon sequestration for other coastal regions.  相似文献   

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In accordance with the concept that only full accounting of major greenhouse gases corresponds to the goals of the United Nations Framework Convention on Climate Change and its Kyoto Protocol, this paper considers uncertainties of regional (national) terrestrial biota Full Carbon Accounting (FCA), both those already achieved and those expected. We analyze uncertainties of major components of the FCA of forest ecosystems of a large boreal region in Siberia (~300 × 106 ha). Some estimates for forests of other regions and Russia as a whole are used for comparison. The systems integration of available information sources and different types of models within the landscape-ecosystem approach are shown to have enabled an estimation of the major carbon fluxes (Net Primary Production, NPP, and heterotrophic respiration, HR) for the region for a single year at the level of 7–12% (confidential interval, CI, 0.9), Net Ecosystem Production (NEP) of 35–40%, and Net Biome Production (NBP) of 60–80%. The most uncertain aspect is the assessment of change in the soil carbon pool, which limits practical application of a pool-based approach. Regionalization of global process-based models, introduction of climatic data in empirical models, use of an appropriate time period for accounting and reporting, harmonization and multiple constraints of estimates obtained by different independent methods decrease the above uncertainties of NEP and NBP by about half. The results of this study support the idea that FCA of forest ecosystems is relevant in the post-Kyoto international negotiation process.  相似文献   

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The contribution of deforestation in Russia to the anthropogenic emission of carbon dioxide (CO2) in 1990–2013 is estimated using the methods of computational monitoring. It is found that since 1990 the area of deforestation and forest conversion to other land-use categories is equal to 628.4 x 103 ha. The respective CO2 emissions from deforestation in Russia for the whole analyzed period are estimated at 142200 kt CO2 with the average annual value of 5900 + 2270 kt CO2/year. The largest contribution to the total losses is made by the changes in soil carbon stock (41.6%) and biomass carbon losses (28.8%). CO2 emissions from deforestation make an insignificant contribution to the total anthropogenic CO2 emission in the country (0.2%). Among the CO2 sources in the land use, land-use change, and forestry sector (LULUCF), the emission from deforestation is the lowest with the average for 1990–2013 contribution of about 0.6%.  相似文献   

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This paper explores concepts of carbon lock-in arising from the technologies of CO2 capture and storage (CCS). We examine the argument that CCS reduces carbon lock-in and the calls for a CCS ‘mandate’ and emission performance standards. We analyse the pros- and cons- of a low-carbon fossil fuel lock-in, arguing that lock-in per se is not the problem; it is rather the depth of lock-in which creates problems because deeper lock-in reduces flexibility and increases the ‘error cost’ (i.e. the cost of a decision which turns out to be based on incorrect understanding) and should be avoided. A set of technical and institutional indicators for measuring the flexibility of different technologies is then presented and applied to three technologies: a landfill gas power generator, a conventional nuclear power plant and a CCS plant under development in California. We conclude that these indicators are a useful way forward in assessing individual projects and that public authorities and other stakeholders might wish to employ some version of these indicators in their deliberations on the role of CCS.  相似文献   

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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   

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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   

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It is increasingly recognized that uncertainty concerns more than statistical errors and incomplete information. Uncertainty becomes particularly important in decision-making when it influences the ability of the decision-makers to understand or solve a problem. While the literature on uncertainty and the way in which uncertainty in decision-making is conceptualized continue to evolve, the many uncertainties encountered in policy development and projects are still mostly represented as individual and separated issues. In this paper, we explore the relationship between fundamentally different uncertainties – which could be classified as unpredictability, incomplete knowledge or ambiguity – and show that uncertainties are not isolated. Based on two case studies of ecological engineering flood defence projects, we demonstrate that important ambiguities are directly related to unpredictability and incomplete knowledge in cascades of interrelated uncertainties. We argue that conceptualizing uncertainties as cascades provides new opportunities for coping with uncertainty. As the uncertainties throughout the cascade are interrelated, this suggests that coping with a particular uncertainty in the cascade will influence others related to it. Each uncertainty in a cascade is a potential node of intervention or facilitation. Thus, if a particular coping strategy fails or system conditions change, the cascades point at new directions for coping with the uncertainties encountered. Furthermore, the cascades can function as an instrument to bridge the gap between actors from science and policy, as it explicitly shows that uncertainties held relevant in different arenas are actually directly related.  相似文献   

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Reducing emissions of greenhouse gases is facilitated by changes in several consumption activities, such as food choices. This paper examines factors explaining red meat consumption in Norway, especially the role of climate concerns. The paper adds to our knowledge as most existing analyses of (red) meat consumption focus on health and animal welfare issues. Moreover, it expands our understanding by drawing on perspectives from both institutional and social psychological theory, including variables emphasizing the social dynamics behind consumption decisions. The study is based on data from a survey of 2000 people aged 18 years or older conducted in 2018. The data are analyzed using structural equation modelling. We find that there is a strong pro-meat culture in Norway, currently rather weakly influenced by climate concerns – specifically, personal norms and social pressures focused on reducing climate impacts. Instead, habits, beliefs about the qualities of red meat (being tasteful, nutritious, healthy) and social norms supporting red meat consumption are the three most important factors explaining the variation observed. Gender and income also influence red meat consumption, but less than found in other studies. The paper discusses policy implications of these findings, including for taxation, point-of-sale information and communicative processes to support changes in the perceptions of what could be a new “normal” diet.  相似文献   

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The holding of doubts about climate change is often referred to as ‘scepticism’. However, there has been a lack of clarity in previous work as to what exactly this scepticism comprises. We integrate data obtained from discussion groups and a nationally representative survey, to interrogate and refine the concept of climate change scepticism with respect to the views of members of the public. We argue that two main types should be distinguished: epistemic scepticism, relating to doubts about the status of climate change as a scientific and physical phenomenon; and response scepticism, relating to doubts about the efficacy of action taken to address climate change. Whilst each type is independently associated by people themselves with climate change scepticism, we find that the latter is more strongly associated with a lack of concern about climate change. As such, additional effort should be directed towards addressing and engaging with people's doubts concerning attempts to address climate change.  相似文献   

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Local government has a crucial role to play in climate change adaptation, both delivering adaptation strategies devised from above and coordinating bottom-up action. This paper draws on a unique longitudinal dataset to measure progress in adaptation by local authorities in Britain, comparing results from a national-scale survey and follow-up interviews conducted in 2003 with a second wave of research completed a decade later. Whereas a decade ago local authority staff were unable to find scientific information that they could understand and use, we find that these technical-cognitive barriers to adaptation are no longer a major problem for local authority respondents. Thanks to considerable Government investment in research and science brokerage to improve the quality and accessibility of climate information, local authorities have developed their adaptive capacity, and their staff are now engaging with the ‘right’ kind of information in assessing climate change risks and opportunities. However, better knowledge has not translated into tangible adaptation actions. Local authorities face substantial difficulties in implementing adaptation plans. Budget cuts and a lack of political support from central government have sapped institutional capacity and political appetite to address long-term climate vulnerabilities, as local authorities in Britain now struggle even to deliver their immediate statutory responsibilities. Local authority adaptation has progressed farthest where it has been rebranded as resiliency to extreme weather so as to fit with the focus on immediate risks to delivering statutory duties. In the current political environment, adaptation officers need information about the economic costs of weather impacts to local authority services if they are to build the business case for adaptation and gain the leverage to secure resources and institutional license to implement tangible action. Unless these institutional barriers are addressed, local government is likely to struggle to adapt to a changing climate.  相似文献   

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The possibility to use the observations of the total ozone values in the atmosphere (TO) in the end of polar winters as the indicator of the cold accumulation in the troposphere and the type of its circulation is considered. The influence of TO over polar regions on the approach of early and late circulation reconstructions in the stratosphere and the following weather type in spring-summer season is concluded.  相似文献   

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A simple method of analysis was proposed to characterize the impact of climatic conditions of a wide region of Argentina (from 27°05′S to 35°48′S, from 61°5′W to 64°21′W) on potential maize (Zea mays L.) grain yield, and the occurrence of various climatic constraints (low temperatures and low soil water content, frost, drought stress and heat stress) along the cycle. The analysis was based on previous studies of the eco-physiology of maize crops and the use of climatic records of six locations in the region under study. Results were analyzed using a probabilistic method, later organized as a checklist to consider when deciding on sowing date in a location of the region. Thus, for each production scenario (combination of location and sowing date), farmers would have a tool enabling them to pay particular attention to the restrictions more likely to occur, to include some cultural practices to avoid or mitigate the most severe climatic constraint to maize production.  相似文献   

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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   

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