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11.
Alethéa E.M. Sallun William Sallun Filho Kenitiro Suguio Marly Babinski Simone M.C.L. Gioia Benjamin A. Harlow Wania Duleba Paulo E. De Oliveira Maria Judite Garcia Cinthia Z. Weber Sérgio R. Christofoletti Camilla da S. Santos Vanda B. de Medeiros Juliana B. Silva Maria Cristina Santiago-Hussein Rosana S. Fernandes 《Quaternary Research》2012,77(1):31-43
The paleoclimatic record of Juréia Paleolagoon, coastal southeastern Brazil, includes cyclic and gradual changes with different intensities and frequencies through geological time, and it is controlled by astronomical, geophysical, and geological phenomena. These variations are not due to one single cause, but they result from the interaction of several factors, which act at different temporal and spatial scales. Here, we describe paleoenvironmental evidence regarding climatic and sea level changes from the last 9400 cal yr BP at the Juréia Paleolagoon — one of the main groups of protected South Atlantic ecosystems. Geochemical evidences were used to identify anomalies from multi-proxy analyses of a paleolagoon sediment core. The anomalies of centennial scale were correlated to climate and transgression–regression cycles from the Holocene period. Decadal scale anomalous oscillations in the Quaternary paleolagoon sediments occur between 9400 and 7500 cal yr BP, correlated with long- and short-term natural events, which generated high sedimentation rates, mainly between 8385 and 8375 cal yr BP (10 cm/yr). Our results suggest that a modern-day short-duration North Atlantic climatic event, such as the 8.2 ka event, could affect the environmental equilibrium in South America and intensify the South American Summer Monsoon. 相似文献
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Ghislain Dubois Benjamin Sovacool Carlo Aall Maria Nilsson Carine Barbier Alina Herrmann Sébastien Bruyère Camilla Andersson Bore Skold Franck Nadaud Florian Dorner Karen Richardsen Moberg Jean Paul Ceron Helen Fischer Dorothee Amelung Marta Baltruszewicz Jeremy Fischer Françoise Benevise Valérie R. Louis Rainer Sauerborn 《Chemie der Erde / Geochemistry》2012
Through their consumption behavior, households are responsible for 72% of global greenhouse gas emissions. Thus, they are key actors in reaching the 1.5 °C goal under the Paris Agreement. However, the possible contribution and position of households in climate policies is neither well understood, nor do households receive sufficiently high priority in current climate policy strategies. This paper investigates how behavioral change can achieve a substantial reduction in greenhouse gas emissions in European high-income countries. It uses theoretical thinking and some core results from the HOPE research project, which investigated household preferences for reducing emissions in four European cities in France, Germany, Norway and Sweden. The paper makes five major points: First, car and plane mobility, meat and dairy consumption, as well as heating are the most dominant components of household footprints. Second, household living situations (demographics, size of home) greatly influence the household potential to reduce their footprint, even more than country or city location. Third, household decisions can be sequential and temporally dynamic, shifting through different phases such as childhood, adulthood, and illness. Fourth, short term voluntary efforts will not be sufficient by themselves to reach the drastic reductions needed to achieve the 1.5 °C goal; instead, households need a regulatory framework supporting their behavioral changes. Fifth, there is a mismatch between the roles and responsibilities conveyed by current climate policies and household perceptions of responsibility. We then conclude with further recommendations for research and policy. 相似文献
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Ghislain Dubois Benjamin Sovacool Carlo Aall Maria Nilsson Carine Barbier Alina Herrmann Sébastien Bruyère Camilla Andersson Bore Skold Franck Nadaud Florian Dorner Karen Richardsen Moberg Jean Paul Ceron Helen Fischer Dorothee Amelung Marta Baltruszewicz Jeremy Fischer Françoise Benevise Rainer Sauerborn 《Chemie der Erde / Geochemistry》2013
Through their consumption behavior, households are responsible for 72% of global greenhouse gas emissions. Thus, they are key actors in reaching the 1.5 °C goal under the Paris Agreement. However, the possible contribution and position of households in climate policies is neither well understood, nor do households receive sufficiently high priority in current climate policy strategies. This paper investigates how behavioral change can achieve a substantial reduction in greenhouse gas emissions in European high-income countries. It uses theoretical thinking and some core results from the HOPE research project, which investigated household preferences for reducing emissions in four European cities in France, Germany, Norway and Sweden. The paper makes five major points: First, car and plane mobility, meat and dairy consumption, as well as heating are the most dominant components of household footprints. Second, household living situations (demographics, size of home) greatly influence the household potential to reduce their footprint, even more than country or city location. Third, household decisions can be sequential and temporally dynamic, shifting through different phases such as childhood, adulthood, and illness. Fourth, short term voluntary efforts will not be sufficient by themselves to reach the drastic reductions needed to achieve the 1.5 °C goal; instead, households need a regulatory framework supporting their behavioral changes. Fifth, there is a mismatch between the roles and responsibilities conveyed by current climate policies and household perceptions of responsibility. We then conclude with further recommendations for research and policy. 相似文献
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A fluorescent labelling method is presented as a new tool for the investigation of organic particle transport and biogenic carbon cycling processes in sandy littoral interstices at Lake Tegel, Berlin, Germany. Passive particle transport through the pore system was studied by in situ exposition of 2.4 μm monodisperse polymeric resin microparticles stained with 7-amino-4-methylcoumarin (AMC). Uptake of fluorescein-5-isothiocyanate (FITC)-labelled Chlorella vulgaris and fine particulate organic matter (FPOM) by the interstitial fauna was investigated in laboratory and field experiments. The major portion (>85%) of the FITC-labelled particles added to sediment cores was recovered from the topmost centimetre of sediment during the study period of 14 days. Uptake of FITC-labelled FPOM was observed in several benthic groups, e.g. chironomids, microcrustaceans, oligochaetes and tardigrads, whereas C. vulgaris was ingested by oligochaetes only. There is evidence to suggest that both are suitable materials for investigating the fragmentation and ingestion of organic material by herbivorous and detritivorous fauna. Field experiments with inert microparticles and FITC-labelled FPOM (<1 mm) prepared from dried alder leaves were carried out in plexiglass tubes as in situ whole core technique. Within the investigation period of two weeks, the transport of FPOM was restricted to the topmost 2–3 cm of sediment in conjunction with a distinct fragmentation to finer size classes with respect to increasing sediment depth. Vertical FPOM transport was hindered by a high interstitial concentration of natural POM and an intensive settlement of the interstices by algae (mainly epispammic algae, 65–96% of algae cell number) and extra-cellular polymeric substances (EPS), which formed a dense three-dimensional structure. 相似文献
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Charter I. Mathison 《Contributions to Mineralogy and Petrology》1987,97(2):228-236
Studies of pyroxene oikocrysts in plagioclase-olivine cumulates crystallised from high alumina olivine tholeiite magmas in layered intrusions inferred to represent periodically replenished magma chambers show that small plagioclases enclosed within the oikocrysts differ significantly from plagioclases in the host rock. Plagioclases within oikocrysts are very elongate with a high surface area, show extensive mutual attachment at high angles resembling skeletal growth, and tend to be randomly orientated. Some are rounded and embayed, are reversely zoned and more sodic by An 5–10 than some of the plagioclase in the host rock. Plagioclase crystal centres tend to be closer spaced in the oikocrysts than in the host rock. In contrast, plagioclases in the host rock are discrete, coarser grained, less elongate, strongly aligned, and locally polygonised.Plagioclases in the oikocrysts are inferred to be self-nucleated clusters resulting from supercooled crystallisation at up to 25–40° C below equilibrium crystallisation temperatures. The oikocrysts crystallised early and are cumulus, and at least some crystallised in place. They are significant because they probably preserved the early condition of the crystal mush. Comparison of plagioclases within the oikocrysts and in the host rocks allows the textural evolution during solidification to be inferred. Features of supercooled plagioclases in the oikocrysts are generally absent beyond the oikocrysts because they were largely overprinted by postcumulus processes involving grainsize coarsening due to selective resorption, and the development of lamination. Supercooling may thus have been more common than is recognised but the inherent disequilibrium of supercooled products made them susceptible to postcumulus overprint except where preserved in early oikocrysts. Thus, much of the cumulus-looking plagioclase in cumulates may not be truly cumulus, but really the result of substantial postcumulus overprint or magmatic diagenesis. 相似文献
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Direct 40Ar/39Ar dating of Late Ordovician and Silurian brittle faulting in the southwestern Norwegian Caledonides 
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下载免费PDF全文 Thomas Scheiber Giulio Viola Camilla Maya Wilkinson Morgan Ganerød Øyvind Skår Deta Gasser 《地学学报》2016,28(5):374-382
Structural data as well as U–Pb zircon and 40Ar/39Ar biotite and muscovite ages were collected from the Rolvsnes granodiorite in western Norway. The granodiorite intruded at c. 466 Ma, cooled quickly and escaped later viscous deformation. Brittle top‐to‐the‐NNW thrust faults (Set I) and WNW–ESE striking dextral strike‐slip faults (Set II) formed in a NNW–SSE transpressional regime. 40Ar/39Ar dating of synkinematic mica from both sets reveals a c. 450 Ma (Late Ordovician) age of faulting, which constrains early‐Caledonian brittle deformation. Set I and II faults are overprinted by a set of lower‐grade, variably oriented chlorite‐ and epidote‐coated faults (Set III) constraining WNW–ESE shortening. A lamprophyric dyke oriented compatibly with this stress field intruded at c. 435 Ma (Silurian), indicating that Set III formed at the onset of the Scandian Baltica–Laurentia collision. The preservation of Caledonian brittle structures indicates that the Rolvsnes granodiorite occupied a high tectonic level throughout the Caledonian orogeny. 相似文献
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Camilla Svensen Lena Seuthe Yulia Vasilyeva Anna Pasternak Edmond Hansen 《Progress in Oceanography》2011,91(4):534-544
We investigated zooplankton distribution in September 2006/2007 at eight stations across Fram Strait in contrasting water masses ranging from cold Polar water to warm Atlantic water. Our main objectives were: (1) to describe the plankton community in the upper 200 m during autumn, and (2) to investigate the importance of small-sized copepods and protozooplankton in an arctic ecosystem when the majority of the large Calanus species had entered diapause. We sampled both with a WP-2 net and Go-Flo bottle and show that small copepods <1 mm are significantly undersampled using a WP-2 net with 90 μm mesh.Small copepods and protozooplankton made a significant contribution both in terms of abundance and total zooplankton biomass at all stations in September, when the large calanoid copepods had left the upper 200 m. The dominating group in the upper 60 m at all stations was Oithona spp. nauplii and their daily estimated grazing potential on the <10 μm phytoplankton ranged from 0.1% to 82% of the standing stock. Both Oithona copepodites and nauplii biomass showed a significantly positive relation with temperature, but not with potential food. Heterotrophic protozooplankton, on the other hand, were most likely bottom-up regulated by the availability of phytoplankton <10 μm. We hypothesise that Oithona nauplii and protozooplankton compete for food and conclude that there was a strong link between the zooplankton community and the microbial food web in Fram Strait. 相似文献
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Future projections of temperature-related climate change impacts on the railway network of Great Britain 总被引：1，自引：0，他引：1
Erika J. Palin Hazel E. Thornton Camilla T. Mathison Rachel E. McCarthy Robin T. Clark John Dora 《Climatic change》2013,120(1-2):71-93
Great Britain’s main line railway network is known to experience various temperature-related impacts, e.g. track buckling and overhead power line sag at high ambient temperatures. Climate change could alter the frequency of occurrence of these impacts. We have therefore investigated the climate change impact on various temperature-related issues, identified during workshops with rail industry specialists, using a perturbed physics ensemble (PPE) of the Met Office’s regional climate model (RCM), HadRM3. We have developed novel approaches to combine RCM data with railway industry knowledge, typically by identifying key meteorological thresholds of interest and analysing exceedance of these out to the 2040s. We performed a statistical analysis of the projected changes for each issue, via bootstrapping of the unperturbed PPE member. Although neither the PPE nor the bootstrapping analysis samples the full range of uncertainty in the projections, they nonetheless provide complementary perspectives on the suitability of the projections for use in decision-making. Our main findings include projected increases in the summertime occurrence of temperature conditions associated with (i) track buckling, (ii) overhead power line sag, (iii) exposure of outdoor workers to heat stress, and (iv) heat-related delays to track maintenance; and (v) projected decreases in the wintertime occurrence of temperatures conditions associated with freight train failure owing to brake problems. For (i), the statistical significance varied with track condition and location; for (ii) and (iii), with location; and for (iv) and (v), projected changes were significant across Great Britain. As well as assessing the changes in climate-related hazard, information about the vulnerability of the network to past temperature-related incidents has been summarised. Combining the hazard and vulnerability elements will eventually support a climate risk assessment for the industry. 相似文献