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41.
Heavy precipitation is one of the most significant natural hazards in the United States today. Knowledge of the climatography, including the temporal characteristics, of this phenomenon is necessary in order to better plan, design for, and predict this hazard. In this study, cluster analysis is used to simplify and clarify the spatial patterns in the time of day heavy precipitation most frequently occurs. Regions with similar diurnal properties are delineated, and the substantial seasonal fluctuations in the regional patterns are traced. Of particular interest is the expansion during the cool season and contraction during the warm season of the nocturnal precipitation regime in the central United States.  相似文献   
42.
The language of transformational change is increasingly applied to climate policy, and particularly in climate finance. Transformational change in this context is used with respect to low-carbon development futures, with the emphasis on mitigation and GHG metrics. But, for many developing countries, climate policy is embedded in a larger context of sustainable development objectives, defined through a national process. Viewed thus, there is a potential tension between mitigation-focused transformation and nationally driven sustainable development. We explore this tension in the context of operationalizing the Green Climate Fund (GCF), which has to deal with the fundamental tension between country ownership and transformational change. In relation to climate finance, acceptance of diverse interpretations of transformation are essential conditions for avoiding risk of transformational change becoming a conditionality on development. We further draw lessons from climate governance and the development aid literature. The article examines how in the case of both the Clean Development Mechanism and Nationally Appropriate Mitigation Actions, there has been limited success in achieving both development objectives and ‘nationally appropriate’ mitigation. The development aid literature points to process-based approaches as a possible alternative, but there are limitations to this approach.

Policy relevance

The concept of transformational change has gained prominence in climate finance. The conundrum facing the GCF is that it seeks to support transformational change in the climate realm, in a context where countries may have competing priorities. Balancing or even transcending this tension is a fundamental design challenge for the GCF. A primary focus on mitigation, particularly if metrics of performance are tied exclusively to GHG reduction, raise concerns about diluting ownership by recipient countries and evokes concerns of conditionality or worse. The literature on development assistance has explored options notably conditions on process and adequate capacity, and suggests that there are no short cuts to building domestic ownership. Actors on climate change need to avoid the risk that transformational change is perceived as, and becomes, an imposed condition. The risk that transformation change, operationalized in the context of unequal power relations, becomes an imposition on development, needs to be avoided.  相似文献   

43.
Zusammenfassung Die Zusammenhänge zwischen Spaltbarkeit und Kristallstruktur werden aufgezeigt. Es werden dieverschiedenen Spalebarkeitsgrade einiger Kristallarten gedeutet, wodurch die bei der Spaltbarkeit wirksamen Faktoren sich zu erkennen geben. Die Vorstellung, daß die dichtest besetzte Netzebéne als beste Spaltfläche auftritt, gilt nicht allgemein und ist nicht ursächlich richtig. Vielmehr hängt Verlauf und Güte der Spaltbarkeit von zwei Faktoren ab: l. Diejenige Netzebene ist die beste Spaltfläche zwischen deren paralleler Schar schwächste Kräftearten (heterodesmische Kristalle) bzw. geringste Anzahl von Bindungen je Flächeneinheit wirksam sind (homodesmische Kristalle). 2. Bei allen nicht stark anisometrischen Kristallen, wenn ihre Bausteine einen — wenn auch nur geringen — heteropolaren Bindungscharakter tragen, muß stets die Bedingung erfüllt sein, daß durch geringe Verschiebung eines Gitterteiles gegenüber dem anderen gleichnamige Ionen einander auf kürzest möglichen Abstand genähert werden können. Dadurch erfolgt elektrostatische Zersprengung des Kristalls parallel einer Ebene. Diese HypotheseJ. Starks wird hier bewiesen, und es wird gezeigt, daß bei Gleichheit der Größe der Bindungskräfte, welche zwischen parallelen Netzebenen im ungestörten Kristall wirksam sind, die Güte der Spaltbarkeit dann am besten ist, wenn nicht nur die nächst-benachbarten sondern auch die übernächsten gleichnamigen Ionen nach Verschiebung des einen Kristallteiles gegenüber dem anderen in Abstoßungsstellung gebracht worden sind.  相似文献   
44.
The Polish Outer Carpathians consist of several flysch series of unknown original basement. They were deposited from Late Jurassic to Miocene in a large basin dissected by tectonically uplifted ridges (cordillieras) which acted as source terrains. The actual nappe pile is correlated with palaeogeographic basin realms. From N to S the Skole, Silesian, Dukla and Magura basins are distinguished. Our paper presents a first compilation of heavy mineral data and pebble analysis in the various turbiditic fan systems. It is assumed that the heavy minerals primarily reflect the nature of basement rocks exposed in the source terrains.The individual flysch basins were supplied generally from unmetamorphosed granitic to highgrade metamorphic continental basement series. But staurolite-bearing high-grade metamorphics appear to have been present only in the northernmost provenance area (Silesian and Subsilesian ridges). A few reworked chromian spinel mineral grains in the northern parts of the basin were derived from small Caledonian/Variscan ultrabasic sutures present in the source ridges. Increased chromian spinel contents are revealed in the southern part of the basin (Maastrichtian-Eocene Magura series) and in Cretaceous Pieniny Klippen belt flysch formations. The chromian spinel in the Magura series was derived, either directly from Alpine oceanic crust obducted in the southern part of the Pieniny realm, or from re-eroded Pieniny flysch series. Hence, our heavy mineral data indicate that in the Outer Carpathian basin during Cretaceous convergence no Alpine ophiolitic crust was obducted. Therefore, an ophiolitic basement to the individual basins appears inprobable. The Outer Carpathians presumably occupied, with respect to the internal suture zone, the position of a deep continental basement floored foreland basin.
Zusammenfassung Die Äußeren Karpathen in Polen bestehen aus mehreren von ihrem Untergrund abgescherten Flysch-Serien, die von oberem Jura bis Miozän in einem Großbecken abgelagert wurden, das durch mehrere tektonisch hochgehobene Rücken (Cordillieren oder Liefergebiete) in Teilbecken gegliedert war. Das ursprüngliche Substrat der verschiedenen Becken ist unbekannt und die heutige Deckenstruktur wird mit der ursprünglichen Beckenanordnung korreliert. Von N nach S werden die Skole-, Silesien-, Duklaund Magura-Becken unterschieden. Die vorliegende Arbeit präsentiert eine erste Zusammenfassung von Schwermineraldaten und Geröllanalysen in den verschiedenen turbiditischen Schüttungssystemen. Dabei wird davon ausgegangen, daß die Schwermineralgehalte der Sandsteine primär die Zusammensetzung des kristallinen Grundgebirges in den Liefergebieten widergeben.Die einzelnen Flyschbecken wurden zumeist von unmetamorphem granitischem bis hochgradig metamorphem kontinentalem Grundgebirge beliefert. Staurolith-führende hochgradige Metamorphite waren jedoch nur in den nördlichst gelegenen Liefergebietsprovinzen (Silesischer und Subsilesischer Rücken) anstehend. Geringe Vorkommen von Chromspinell in den nördlichen Beckenteilen stammen von kleineren caledonisch/variszischen ultrabasischen Einschlüssen (Suturen) in den Cordillieren. Erhöhte Chromspinellgehalte werden nur im südlichen Becken (Maastricht bis Tertiär des Magura-Beckens) und in kretazischen Flyschen der Pieniny-Klippen festgestellt. Der Chromspinell in den Magura-Serien stammt von alpiner ozeanischer Kruste, die während der Kreide im südlichen Pieniny-Raume obduziert wurde oder von neuerlich erodierten Flyschen aus den Pieniny-Becken. Unsere Schwermineraldaten weisen folglich darauf hin, daß während der kretazischen tektonischen Konvergenz im Bereich der Äußeren Karpathen keine alpin gebildete ophiolithische Kruste aufgeschuppt wurde. Die Anwesenheit eines ozeanischen Untergrundes der einzelnen Teilbecken erscheint deshalb unwahrscheinlich. Die Äußeren Karpathen nahmen deshalb vermutlich gegenüber der internen Suturzone die Stellung eines tiefen Foreland-Beckens über kontinentaler Kruste ein.

Résumé Les Carpathes externes, en Pologne, sont composées de plusieurs séries de flysch d'âge jurassique à miocène déposées dans un grand bassin alimenté par l'érosion de rides tectoniques internes et externes (cordillères). Ces séries de flysch sont préservées en nappes, classiquement corrélées avec différents domaines paléogéographiques du bassin. Le substratum originel de ces bassins individuels n'est pas connu et reste discuté. On distingue, du nord au sud, les bassins de Skole, de Silésie, de Dukla et de Magura. Nous présentons ici les premiers résultats de l'analyse des minéraux lourds et des lithoclastes reconnus dans les principaux éventails turbiditiques sous-marins. Nous partons de l'hypothèse que le contenu des grès en minéraux lourds reflète la nature du socle cristallin qui était à l'affleurement dans les diverses régions-source.D'une manière générale, les bassins de flysch ont été alimentés par des terrains granitiques non métamorphiques et par des formations métamorphiques de moyenne et haute température. Il semble cependant que les terrains métamorphiques de haut degré à staurotide étaient présents seulement dans les sources les plus septentrionales (rides silésienne et subsilésienne). Le spinelle chromifère présent en petite quantité dans la partie nord du bassin peut être expliqué par la présence d'inclusions ultramafiques calédoniennes ou varisques (zones de sutures) dans les cordillères. Une proportion élevée de grains de spinelle chromifère ne s'observe que dans la partie méridionale du bassin des Carpathes externes (séries maastrichtiennes et tertiaires du bassin de Magura) et dans les flyschs crétacés des clippes de Pieniny. Il est suggéré que le spinelle chromifère du bassin de Magura a été fourni par la croûte océanique alpine, obductée au cours du Crétacé dans la partie interne du domaine des clippes de Pieniny, ou par l'érosion secondaire des flyschs de Pieniny.La rareté et l'origine probablement ancienne des spinelles chromifères dans la partie septentrionale indique que lors des mouvements convergents crétacés aucune roche ophiolitique alpine n'était exposée à l'érosion. Par conséquent, la présence de fonds océaniques dans ces bassins individuels semble peu probable. Les Carpathes externes représentent probablement un bassin profond, de type «foreland» par rapport à une zone de suture ophiolitique plus interne.

, , , . , . : Skole, Silesien, Dukla Magura. . , . , . , , , , , .. . - () . ( ) Pieniny . , Pieniny, . , , . , , . .. , .
  相似文献   
45.
The hottentot seabream Pachymetopon blochii is a small-sized (maximum 2.67 kg) sparid endemic to southern Africa. It is an important target in South Africa's Western Cape traditional linefishery, particularly in the absence of more valuable pelagic species (such as Thyrsites atun and Seriola lalandi). In 2000, South Africa's linefishery was declared to be in a state of emergency, and commercial fishing effort was consequently reduced by 70%. A subsequent increase in stock biomass and intraspecific competition, coupled with environmental changes, were hypothesised to have thereafter altered the growth rate of hottentot, from 2000 to 2010. This study aimed to revise outdated age–growth models for the hottentot by using modern techniques (sectioned otoliths), and to compare age–growth relationships before and after the declared linefish state of emergency. The maximum age observed was 19 years, with no difference in the growth rate between sexes (p = 0.39–0.43) or time-periods (p = 0.96). Although the growth rate did not change, there is evidence that the age structure of the stock changed between time-periods as a result of changes in fishing pressure between 2000 and 2010. The enhanced recent growth model for hottentot, described as Lt = 418.063 (1 – e?0.104(t – [?4.709])) (pooled sexes; n = 206), indicates a considerably slower growth rate for this species than was proposed previously using whole otoliths and has major implications for effective stock management.  相似文献   
46.
The retro‐arc foreland Andean Amazon Basin records sedimentary infill from the South American craton and the emerging Northern Andean chain from the middle Cretaceous until Present day. The U/Pb ages of detrital zircons indicate significant reworking of Archean‐Proterozoic (max. 2.9 Ga) and Paleozoic crust and sediments, which were eroded on both sides. Heavy mineral associations show that the material derived from Proterozoic craton was supplied by Cretaceous reworking of non‐metamorphosed (unannealed) Paleozoic and older sedimentary rocks, which cover the Amazon Craton. Following latest Cretaceous switch of the dominant sediment source to the Andean cordillera, the influx of Precambrian zircons persisted, and these zircons were derived from the metamorphosed basement and Paleozoic sediments of the Cordillera Real (Loja terrane). Re‐evaluation of existing detrital zircon fission‐track record proves that the rise of the Cordillera Real at the Cretaceous‐Tertiary transition was initiated by the collision of Caribbean Oceanic Plateau and associated arc elements from 75–65 Ma. A further important exhumation event also occurred in the Late Oligocene, which is correlated with the break‐up of the Farallon plate.  相似文献   
47.
48.
49.
Heterogeneous nucleation of supersaturated n-nonane vapour on seed particles of different size and composition has been investigated using a fast expansion chamber. Monodisperse seed particle sizes were ranging from about 4 nm up to about 24 nm in diameter. By using different types of particle generators WOx, Ag and (NH4)2SO4 particles were generated. For direct comparison between different particle compositions overlapping sizes have been generated for WOx and Ag at about 7 nm particle diameter as well as for Ag and (NH4)2SO4 at about 15 nm. Nucleation temperature was kept constant at about 278 K. Experimental data were compared to Kelvin equation and Fletcher theory including the effect of line tension. It was found that heterogeneous nucleation of n-nonane seems to be independent of seed particle composition and starts well below the Kelvin curve. Good agreement was achieved with Fletcher theory including the effect of line tension.  相似文献   
50.
Having been in use at Hohenpeissenberg from 1781–1841, the Palatina thermometer was found to suffer from a positive bias of 0.5°R (or 0.63°C) as discovered by Lamont following a re-calibration made in 1842. The main reason was due to the composition of the glass used during the early instrumental period. Glass of this period tended to contract over many years due to thermal aftereffects, resulting in a gradual rise of the freezing point position in consequence of the shrinking bulb forming the mercury reservoir. While the problem of the gradually rising zero point was recognised relatively early, the reason was attributed to wrong causes. Around 1880, scientists recognised that the chemical composition of glass might be responsible for the drift of the zero point. New glass types were developed which were free from such effects. Although these facts became known, no correction was applied to the Hohenpeissenberg temperature series when in 1981, the complete 200-year series was published. Most probably this bias is also relevant for other stations, at least those of the network of the Societas Meteorologica Palatina that were supplied with thermometers manufactured in Mannheim. Another problem originates from the different observing times for the period 1879–1900, which were set to 0800, 1400 and 2000 hours instead of 0700, 1400 and 2100 hours before and afterwards. In addition, a new formula to calculate the daily mean was established resulting in the temperature being too low by 0.5°C in that period. The overall trend changes after application of the two necessary corrections. There remain two biases that cannot be quantified without a major detailed study being made: (1) At the start of the observations, the window of the observation room was always kept “open during dry weather”. It is not known how long this practice was remained in use. (2) Lamont also employed an easily melting glass to construct his thermometers which in use between 1841 and 1878. An analysis of the glass composition seems to be necessary to find out whether it also suffered from a rising freezing point. Lamont replaced the Hohenpeissenberg thermometer in 1842 by a new instrument produced in his own workshop. One still existing Lamont thermometer, but not that one of Hohenpeissenberg, was re-calibrated and the zero point found to have lowered by ?1.4°C. Since the opposite drift had been expected and the original Lamont-type Hohenpeissenberg thermometer is no longer available, no correction is justified for the period in which this thermometer was in use.  相似文献   
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