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961.
The structure and operation of an automated hardware-software complex, in use in the Far East Division of the USSR Academy of Sciences (Vladivostok) to generate multicolor thematic maps for planning purposes, is described. Particularly noteworthy are adjustments, in the form of special interfaces, necessitated by the incompatibility of standard Soviet mainframe computers with the kinds of input-output devices commonly used in the West—notably the color display and graphics systems used to produce the final maps. Both preexisting maps and remote sensing imagery served, after digitization, as source materials. Translated from: Geografiya i prirodnyye resursy, 1986, No. 3, pp. 122-125.  相似文献   
962.
Zusammenfassung In der vorliegenden Arbeit werden neue Klassifikationsprinzipien für Großwetterlagen entwickelt. Bisher wurde bei Wetterlagenklassifikationen das Druckfeld zugrunde gelegt, wobei quasistationären Druckzentren eine nicht berechtigte Vorrangstellung eingeräumt wurde. In der hier versuchten Klassifikation wird vom Strömungsfeld ausgegangen, das in elementare Formen zerlegt wird. Eine zu diesem Zweck durchgeführte statistische Untersuchung ergab, daß alle im Strömungsfeld auftretenden Zirkulationstypen auf drei Grundformen zurückgeführt werden können. Diese Grundformen sind:Driften, Wellen undWirbel.Die Untersuchung ergab im einzelnen, daß in mittleren Breiten der nördlichen Hemisphäre bei 49% aller untersuchten Fälle Driften, bei 23% Wellen und bei 28% Wirbel auftraten.In der hier durchgeführten Klassifikation wird das Druckfeld durch das Strömungsfeld und der Begriff Großwetterlage durch den umfassenderen Begriff des Zirkulationstyps ersetzt. Damit wird der unberechtigte Vorrang der Druckformen bei der Wetterlagenklassifikation aufgegeben. Die Klassifizierung der Zirkulationstypen ergibt sich schließlich durch Kombination der drei Zirkulationselemente: Drift, Welle und Wirbel.
Summary New principles of classification for large-scale weather situations are outlined in this paper. Hitherto the pressure-field has been taken as a basis for such classifications by conceding a precedence of an unjustified position to semi-permanent centres of pressure. The new classification starts from the field of large-scale motions, which is dissected in elementary models. A statistical test yielded the possibility to reduce all types of atmospheric circulations in the following three elementary models:drifts, waves andeddies.In detail it was found out, that drifts occur in 49%, waves in 23% and eddies in 28% of all cases investigated.In the new classification the term pressure-field is substituted by field of motion and the expression large-scale weather situation by the more comprehensive conception type of circulation. By that the unjustified priority of pressure-centers in classifying weather situations is abolished. At last the classification of the types of circulation follows from a combination of the three elementary models: drift, wave and eddy.

résumé La présente étude développe de nouveaux principes de classification des situations météorologiques. Alors que jusqu'ici on s'est fondé sur le champ de pression ce qui conduisait à attribuer aux centres d'action quasi stationnaires un rôle trop important, l'auteur part ici du champ de mouvement décomposé en formes élémentaires. Un examen statistique lui a montré que tous les types de circulation peuvent se ramener à trois formes fondamentales:courants, ondulations ettourbillons.Aux latitudes moyennes de l'hémisphère Nord les courants représentent le 49%, les ondulations le 23% et les tourbillons le 28%.Au champ de pression se substitue donc le champ de courant, et les situations météorologiques se groupent en types de circulation ce qui supprime le rôle prépondérant des formes isobariques. Le classement final des types de circulation résulte de la combinaison des trois types mentionnés:courants, ondulations ettourbillons.


Mit 15 Textabbildungen  相似文献   
963.
 Application of an ice sheet model developed for the Pleistocene to the extensive Carboniferous glaciation on Gondwana yields an ice sheet which has several features consistent with observations. While complete deglaciation is not achieved without CO2 changes, the Milankovich-induced fluctuations in ice sheet volume are comparable to Pleistocene glacial/ interglacial signals. This result is shown to hold for a large fraction of physically reasonable parameter space. The model also exhibits multiple equilibria and sharp bifurcations, as infinitesimal changes in the solar constant or precipitation can lead to a qualitatively different climate. The success of the model in predicting ice location in an environment quite different from the Pleistocene provides additional support for the robustness of the basic model physics and suggests that the model can be applied with some confidence to other pre-Pleistocene glaciations. Received: 30 June 1998 / Accepted: 5 January 1999  相似文献   
964.
Although agriculture could contribute substantially to European emission reductions, its mitigation potential lies untapped and dormant. Market-based instruments could be pivotal in incentivizing cost-effective abatement. However, sector specificities in transaction costs, leakage risks and distributional impacts impede its implementation. The significance of such barriers critically hinges on the dimensions of policy design. This article synthesizes the work on emissions pricing in agriculture together with the literature on the design of market-based instruments. To structure the discussion, an options space is suggested to map policy options, focusing on three key dimensions of policy design. More specifically, it examines the role of policy coverage, instruments and transfers to farmers in overcoming the barriers. First, the results show that a significant proportion of agricultural emissions and mitigation potential could be covered by a policy targeting large farms and few emission sources, thereby reducing transaction costs. Second, whether an instrument is voluntary or mandatory influences distributional outcomes and leakage. Voluntary instruments can mitigate distributional concerns and leakage risks but can lead to subsidy lock-in and carbon price distortion. Third, the impact on transfers resulting from the interaction of the Common Agricultural Policy (CAP) with emissions pricing will play a key role in shaping political feasibility and has so far been underappreciated.

POLICY RELEVANCE

Following the 2015 Paris Agreement, European climate policy is at a crossroads. Achieving cost-effectively the 2030 and 2050 European targets requires all sectors to reduce their emissions. Yet, the cornerstone of European climate policy, the European Union Emissions Trading System (EU ETS), covers only about half of European emissions. Major sectors have been so far largely exempted from carbon pricing, in particular transport and agriculture. While transport has been increasingly under the spotlight as a possible candidate for an EU ETS sectoral expansion, policy discussions on pricing agricultural emissions have been virtually absent. This article attempts to fill this gap by investigating options for market-based instruments to reduce agricultural emissions while taking barriers to implementation into account.  相似文献   

965.
DNA single-strand breaks were measured by the comet assay in both gill and hemolymph cells of mussels collected in 3 sampling areas of the French coast (Pointe du Castelli, Pen Bron and Saint-Nazaire Harbour). Whole mussel tissue samples were also collected for the chemical determination of PAH, PCB and heavy metal concentrations. In mussel, a higher level of DNA strand breaks was measured in gill than in hemolymph cells (p < 0.01). Despite a factor of contamination from 2 to 3 between sites, no difference in the extent of mussel DNA strand breaks was shown between sampling locations (p > 0.05), questioning the sensitivity of the assays used in biomonitoring studies.  相似文献   
966.
In this study male largemouth bass (LMB) were exposed to the naturally occurring androgens, dihydrotestosterone (DHT) or 11-ketotestosterone (11-KT) in order to identify genes that are differentially regulated by these steroid hormones. Using subtractive hybridization on livers of fish treated with DHT against vehicle control, many novel LMB genes were cloned. These genes were added to our gene library and arrayed. Six genes were up-regulated and five were down-regulated by both androgens. But, each androgen also regulated specific genes. One gene that was identified as a potential androgen marker was spermidine-spermine-N(1)-acetyltransferase that was up-regulated by both androgens. Determining which genes are responsive to natural androgens will help to identify biochemical pathways that are impacted.  相似文献   
967.
968.
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970.
This issue marks a change in the editorial team of the ICESJournal of Marine Science, in that we have bid farewell to ourformer Editor-in-Chief, Niels Daan, after six years of sterlingservice, and to our Elsevier Publishing Editor, Andrew Richford,after an even longer period of years. Both deserve credit fortheir energy and vision that has left us the legacy of a journalas widely read and cited as the ICES Journal now is, but theyleave a gap that will be a huge challenge for us to meet. However,in my new capacity as Editor-in-Chief and in Els Bosma's capacityas Elsevier's Publishing Editor, I  相似文献   
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