653 resultados para Retreat


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We present ocean model sensitivity experiments aimed at separating the influence of the projected changes in the “thermal” (near-surface air temperature) and “wind” (near-surface winds) forcing on the patterns of sea level and ocean heat content. In the North Atlantic, the distribution of sea level change is more due to the “thermal” forcing, whereas it is more due to the “wind” forcing in the North Pacific; in the Southern Ocean, the “thermal” and “wind” forcing have a comparable influence. In the ocean adjacent to Antarctica the “thermal” forcing leads to an inflow of warmer waters on the continental shelves, which is somewhat attenuated by the “wind” forcing. The structure of the vertically integrated heat uptake is set by different processes at low and high latitudes: at low latitudes it is dominated by the heat transport convergence, whereas at high latitudes it represents a small residual of changes in the surface flux and advection of heat. The structure of the horizontally integrated heat content tendency is set by the increase of downward heat flux by the mean circulation and comparable decrease of upward heat flux by the subgrid-scale processes; the upward eddy heat flux decreases and increases by almost the same magnitude in response to, respectively, the “thermal” and “wind” forcing. Regionally, the surface heat loss and deep convection weaken in the Labrador Sea, but intensify in the Greenland Sea in the region of sea ice retreat. The enhanced heat flux anomaly in the subpolar Atlantic is mainly caused by the “thermal” forcing.

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The Arctic sea ice retreat has accelerated over the last decade. The negative trend is largest in summer, but substantial interannual variability still remains. Here we explore observed atmospheric conditions and feedback mechanisms during summer months of anomalous sea ice melt in the Arctic. Compositing months of anomalous low and high sea ice melt over 1979–2013, we find distinct patterns in atmospheric circulation, precipitation, radiation, and temperature. Compared to summer months of anomalous low sea ice melt, high melt months are characterized by anomalous high sea level pressure in the Arctic (up to 7 hPa), with a corresponding tendency of storms to track on a more zonal path. As a result, the Arctic receives less precipitation overall and 39% less snowfall. This lowers the albedo of the region and reduces the negative feedback the snowfall provides for the sea ice. With an anticyclonic tendency, 12 W/m2 more incoming shortwave radiation reaches the surface in the start of the season. The melting sea ice in turn promotes cloud development in the marginal ice zones and enhances downwelling longwave radiation at the surface toward the end of the season. A positive cloud feedback emerges. In midlatitudes, the more zonally tracking cyclones give stormier, cloudier, wetter, and cooler summers in most of northern Europe and around the Sea of Okhotsk. Farther south, the region from the Mediterranean Sea to East Asia experiences significant surface warming (up to 2.4◦C), possibly linked to changes in the jet stream.

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Considerable progress has been made in understanding the present and future regional and global sea level in the 2 years since the publication of the Fifth Assessment Report (AR5) of the Intergovernmental Panel on Climate Change. Here, we evaluate how the new results affect the AR5’s assessment of (i) historical sea level rise, including attribution of that rise and implications for the sea level budget, (ii) projections of the components and of total global mean sea level (GMSL), and (iii) projections of regional variability and emergence of the anthropogenic signal. In each of these cases, new work largely provides additional evidence in support of the AR5 assessment, providing greater confidence in those findings. Recent analyses confirm the twentieth century sea level rise, with some analyses showing a slightly smaller rate before 1990 and some a slightly larger value than reported in the AR5. There is now more evidence of an acceleration in the rate of rise. Ongoing ocean heat uptake and associated thermal expansion have continued since 2000, and are consistent with ocean thermal expansion reported in the AR5. A significant amount of heat is being stored deeper in the water column, with a larger rate of heat uptake since 2000 compared to the previous decades and with the largest storage in the Southern Ocean. The first formal detection studies for ocean thermal expansion and glacier mass loss since the AR5 have confirmed the AR5 finding of a significant anthropogenic contribution to sea level rise over the last 50 years. New projections of glacier loss from two regions suggest smaller contributions to GMSL rise from these regions than in studies assessed by the AR5; additional regional studies are required to further assess whether there are broader implications of these results. Mass loss from the Greenland Ice Sheet, primarily as a result of increased surface melting, and from the Antarctic Ice Sheet, primarily as a result of increased ice discharge, has accelerated. The largest estimates of acceleration in mass loss from the two ice sheets for 2003–2013 equal or exceed the acceleration of GMSL rise calculated from the satellite altimeter sea level record over the longer period of 1993–2014. However, when increased mass gain in land water storage and parts of East Antarctica, and decreased mass loss from glaciers in Alaska and some other regions are taken into account, the net acceleration in the ocean mass gain is consistent with the satellite altimeter record. New studies suggest that a marine ice sheet instability (MISI) may have been initiated in parts of the West Antarctic Ice Sheet (WAIS), but that it will affect only a limited number of ice streams in the twenty-first century. New projections of mass loss from the Greenland and Antarctic Ice Sheets by 2100, including a contribution from parts of WAIS undergoing unstable retreat, suggest a contribution that falls largely within the likely range (i.e., two thirds probability) of the AR5. These new results increase confidence in the AR5 likely range, indicating that there is a greater probability that sea level rise by 2100 will lie in this range with a corresponding decrease in the likelihood of an additional contribution of several tens of centimeters above the likely range. In view of the comparatively limited state of knowledge and understanding of rapid ice sheet dynamics, we continue to think that it is not yet possible to make reliable quantitative estimates of future GMSL rise outside the likely range. Projections of twenty-first century GMSL rise published since the AR5 depend on results from expert elicitation, but we have low confidence in conclusions based on these approaches. New work on regional projections and emergence of the anthropogenic signal suggests that the two commonly predicted features of future regional sea level change (the increasing tilt across the Antarctic Circumpolar Current and the dipole in the North Atlantic) are related to regional changes in wind stress and surface heat flux. Moreover, it is expected that sea level change in response to anthropogenic forcing, particularly in regions of relatively low unforced variability such as the low-latitude Atlantic, will be detectable over most of the ocean by 2040. The east-west contrast of sea level trends in the Pacific observed since the early 1990s cannot be satisfactorily accounted for by climate models, nor yet definitively attributed either to unforced variability or forced climate change.

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Balkanisation is a way to describe the breakdown of cross-border banking, as nervous lenders retreat in particular from the more troubled parts of the Eurozone or at least try to isolate operations within national boundaries. It is increasing at the Bank level, however the senior policy makers consider this a negative trend – Mario Draghi, president of the European Central Bank, has talked of the need to “repair this financial fragmentation” and Mark Carney, head of global regulatory body the Financial Stability Board, [and now Governor of the Bank of England] has warned that deglobalising finance will hurt growth and jobs by “reducing financial capacity and systemic resilience”. In this article I would like to examine the impact of banking balkanisation on international trade and provide some initial thoughts about remedies for excessive risk in a banking non-balkanising world.

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SHIMMER (Soil biogeocHemIcal Model for Microbial Ecosystem Response) is a new numerical modelling framework designed to simulate microbial dynamics and biogeochemical cycling during initial ecosystem development in glacier forefield soils. However, it is also transferable to other extreme ecosystem types (such as desert soils or the surface of glaciers). The rationale for model development arises from decades of empirical observations in glacier forefields, and enables a quantitative and process focussed approach. Here, we provide a detailed description of SHIMMER, test its performance in two case study forefields: the Damma Glacier (Switzerland) and the Athabasca Glacier (Canada) and analyse sensitivity to identify the most sensitive and unconstrained model parameters. Results show that the accumulation of microbial biomass is highly dependent on variation in microbial growth and death rate constants, Q10 values, the active fraction of microbial biomass and the reactivity of organic matter. The model correctly predicts the rapid accumulation of microbial biomass observed during the initial stages of succession in the forefields of both the case study systems. Primary production is responsible for the initial build-up of labile substrate that subsequently supports heterotrophic growth. However, allochthonous contributions of organic matter, and nitrogen fixation, are important in sustaining this productivity. The development and application of SHIMMER also highlights aspects of these systems that require further empirical research: quantifying nutrient budgets and biogeochemical rates, exploring seasonality and microbial growth and cell death. This will lead to increased understanding of how glacier forefields contribute to global biogeochemical cycling and climate under future ice retreat.

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This article investigates fiscal policy responses to the Great Recession in historical perspective. We explore general trends in the frequency, size and composition of fiscal stimulus as well as the impact of government partisanship on fiscal policy outputs during the four international recessions of 1980-81, 1990-91, 2001-02 and 2008-09. Encompassing 17-23 OECD countries, our analysis calls into question the idea of a general retreat from fiscal policy activism since the early 1980s. The propensity of governments to respond to economic downturns by engaging in fiscal stimulus has increased over time and we do not observe any secular trend in the size of stimulus measures. At the same time, OECD governments have relied more on tax cuts to stimulate demand in the two recessions of the 2000s than they did in the early 1980s or early 1990s. Regarding government partisanship, we do not find any significant direct partisan effects on either the size or the composition of fiscal stimulus for any of the four recession episodes. However, the size of the welfare state conditioned the impact of government partisanship in the two recessions of the 2000s, with Left-leaning governments distinctly more prone to engage in discretionary fiscal stimulus and/or spending increases in large welfare states, but not in small welfare states.

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The Indian author Rabindranath Tagore was received like royalty during his visits to the West after winning the Nobel Prize in 1913. Dreams of foreign cultures offered a retreat from a complicated age. In a time when the West appeared to be living under threat of disintegration and when industrialism seemed like a cul-de-sac, he appeared to offer the promise of a return to a lost paradise, a spiritual abode that is superior to the restless Western culture. However, Tagore’s popularity faded rapidly, most notably in England, the main target of his criticism. Soon after Tagore had won the Nobel Prize, the English became indignant at Tagore’s anti-colonial attitude.Tagore visited Sweden in 1921 and 1926 and was given a warm reception. His visits to Sweden can be seen as an episode in a longer chain of events. It brought to life old conceptions of India as the abode of spirituality on earth. Nevertheless, interest in him was a relatively short-lived phenomenon in Sweden. Only a few of his admirers in Sweden appreciated the complexity of Tagore’s achievements. His “anathema of mammonism”, as a Swedish newspaper called it, was not properly received. After a steady stream of translations his popularity flagged towards the end of the 1920s and then almost disappeared entirely. Tagores visits in Sweden gave an indication that India was on the way to liberate itself from its colonial legacy, which consequently contributed to the waning of his popularity in the West. In the long run, his criticism of the drawbacks in the western world became too obvious to maintain permanent interest. The Russian author Fyodor Dostoyevskiy’s Crime and Punishment (1866) has enticed numerous interpretations such as the purely biographical approach. In the nervous main character of the novel, the young student Raskolnikov, one easily recognizes Dostoyevskiy himself. The novel can also be seen as a masterpiece of realistic fiction. It gives a broad picture of Saint Petersburg, a metropolis in decay. Crime and Punishment can also be seen as one of the first examples of a modern psychological novel, since it is focused on the inner drama of its main character, the young student Raskolnikov. His actions seem to be governed by mere coincidences, dreams and the spur of the moment. it seems fruitful to study the novel from a psychoanalytical approach. In his book Raskolnikov: the way of the divided towards unity in Crime and Punishment (1982), a Swedish scholar, Owe Wikström, has followed this line of interpretation all the way to Freud’s disciple C G Jung. In addition to this, the novel functions as an exciting crime story. To a large extent it is Viktor Sjklovskij and other Russian formalists from the 1920s and onwards who have taught the western audience to understand the specific nature of the crime story. The novel could be seen as a story about religious conversion. Like Lasarus in the Bible (whose story attracts a lot of attention in the novel) Raskolnikov is awakened from the dead, and together with Sonja he starts a completely new life. The theme of conversion has a special meaning for Dostoyevskiy. For him the conversion meant an acknowledgement of the specific nature of Russia itself. Crime and punishment mirrors the conflict between traditional Russian values and western influences that has been obvious in Russia throughout the history of the country. The novel reflects a dialogue that still continues in Russian society. The Russian literary historian Mikhail Bakhtin, who is probably the most famous interpreter of the works of Dostoyevskiy, has become famous precisely by emphasizing the importance of dialogues in novels like Crime and Punishment. According to Bakhtin, this novel is characterized by its multitude of voices. Various ideas are confronted with each other, and each one of them is personified by one of the characters in the novel. The author has resigned from his position as the superior monitor of the text, and he leaves it to the reader to decide what interpretation is the correct one..The aim of the present study is thus to analyze the complex reactions in the west to Tagore’s visits in Sweden and to Fyodor Dostoyevskiys novel Crime and Punishment.. This leads to more general conclusions on communication between cultures.

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Vertical stream bed erosion has been studied routinely and its modeling is getting widespread acceptance. The same cannot be said with lateral stream bank erosion since its measurement or numerical modeling is very challenging. Bank erosion, however, can be important to channel morphology. It may contribute significantly to the overall sediment budget of a stream, is a leading cause of channel migration, and is the cause of major channel maintenance. However, combined vertical and lateral channel evolution is seldom addressed. In this study, a new geofluival numerical model is developed to simulate combined vertical and lateral channel evolution. Vertical erosion is predicted with a 2D depth-averaged model SRH-2D, while lateral erosion is simulated with a linear retreat bank erosion model developed in this study. SRH-2D and the bank erosion model are coupled together both spatially and temporally through a common mesh and the same time advancement. The new geofluvial model is first tested and verified using laboratory meander channels; good agreement are obtained between predicted bank retreat and measured data. The model is then applied to a 16-kilometer reach of Chosui River, Taiwan. Vertical and lateral channel evolution during a three-year period (2004 to 2007) is simulated and results are compared with the field data. It is shown that the geofluvial model correctly captures all major erosion and deposition patterns. The new model is shown to be useful for identifying potential erosion sites and providing information for river maintenance planning.

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This thesis aims to study the impact of structural change on the trajectory of development of emerging economies. More speci cally, we seek to understand how the reallocation of labor from less productive sectors of the economy (e.g., agriculture) to more productive sectors (e.g., industry and services) contributed to the growth of labor productivity in these economies. The thesis is divided into three chapters, besides the introduction. The rst chapter studies the relationship between structural change and economic development in Latin American economies. While the process of reallocation of labor was important to the dynamics of productivity in the period of convergence of these economies, low productivity in some sectors of the economy explained most of the reduction in productivity in the most recent period. In the second chapter, I study the main determinants of growth of the Chinese economy between 1980 and 2005. I show that the increased ow of trade and strong productivity growth in the agricultural sector contributed signi -cantly to China s development in the period. In the third chapter, I study the apparent contradiction between increased levels of schooling and reduction of per capita income in African economies compared to the U.S. economy. The main conclusion is that reducing educational costs explain the retreat of the education di¤erential between African economies and the United States.

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O presente trabalho foi realizado em condições de ripado, com o objetivo de avaliar o desempenho da enxertia a inglês simples, em dois tipos de porta-enxerto (pé-franco e alporquia), em combinação com três tipos de anelamento do ramo (sem anelamento, e ramos anelados duas e quatro semanas antes da retirada do garfo), em lichia. O experimento foi conduzido em delineamento inteiramente casualizado, com seis tratamentos e três repetições. Foi somente observada diferença significativa para o tipo pé-franco, que revelou os melhores resultados.

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Os experimentos foram conduzidos para avaliar a digestibilidade ileal (CDILEAL) e total (CDTOTAL) do amido e a atividade das enzimas amilase (ATAM) e maltase (ATMAL) em coelhos de 35 e 45 dias alimentados com amido proveniente do milho ou da raspa de mandioca. em cada ensaio foram utilizados 20 coelhos da raça Nova Zelândia Branco, sendo dez machos e dez fêmeas, alojados individualmente em gaiolas de arame e distribuídos em um delineamento inteiramente casualizado. Ao final do período experimental, os animais foram abatidos para retirada de uma amostra do conteúdo digestivo de uma porção do jejuno e do íleo. Os CDILEAL e CDTOTAL do amido da raspa de mandioca (59,25±1,38% e 99,89±0,04%, respectivamente) foram superiores ao do milho (54,21±1,51% e 99,21±0,05%, respectivamente). O CDTOTAL dos animais com 45 dias de idade foi superior ao dos com 35 dias (99,75±0,04% vs 99,35±0,05%). A ATAM, no conteúdo do jejuno e do íleo, foi maior nos animais com 45 dias (0,952±0,118 mmol de glicose/mg/min e 0,647±0,093 mmol de glicose/mg/min, respectivamente) do que nos de 35 (0,469±0,111 mmol de glicose/mg/min e 0,375±0,088 mmol de glicose/mg/min, respectivamente). A ATMAL foi maior nos animais alimentados com raspa de mandioca do que nos que receberam milho (0,061±0,007 mmol de glicose/mg/min vs 0,032±0,007 mmol de glicose/mg/min). Conclui-se que o amido da raspa de mandioca é mais digestível que o do milho, e o sistema enzimático dos coelhos com 35 dias de idade ainda não está suficientemente desenvolvido para que ocorra otimização da digestão do amido.

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The hardness test is thoroughly used in research and evaluation of materials for quality control. However, this test results are subject to uncertainties caused by the process operator in the moment of the mensuration impression diagonals make by the indenter in the sample. With this mind, an automated equipment of hardness mensuration was developed. The hardness value was obtained starting from the mensuration of plastic deformation suffered by the material to a well-known load. The material deformation was calculated through the mensuration of the difference between the progress and retreat of a diamond indenter on the used sample. It was not necessary, therefore, the manual mensuration of the diagonals, decreasing the mistake source caused by the operator. Tension graphs of versus deformation could be analyzed from data obtained by the accomplished analysis, as well as you became possible a complete observation of the whole process. Following, the hardness results calculated by the experimental apparatus were compared with the results calculated by a commercial microhardness machine with the intention of testing its efficiency. All things considered, it became possible the materials hardness mensuration through an automated method, which minimized the mistakes caused by the operator and increased the analysis reliability

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The structure of the worlds we know is built on habits and is conditioned by fixed beliefs through which we filter and conform a circumscribed universe. This building process makes it essential to understand the paths of the Information capture and recontextualization as well as to elucidate the involvement of principles or laws that regulate and structure the ways we think and act creatively in contemporary times. The proposal of this article is to point out that Information Science, while studying the set of changes related to the establishment of new habits of the Information Society, should also provide relevant sociocultural indicators for the understanding of our historical moment. In this realm, it presents few extracted moments from the context of these changes that regard to the continuum of the shared information and knowledge desires. The procedure requires a significant retreat of the viewpoint, simultaneously placing such a movement in the scope of relations between habit and break as movements that weave relations of the world, of humankind and of distinct cultural changes.

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Through the comparative critical analysis of the demanded urbanistic parameters in the legislation and of the urbanistic index found in the Rocas neighbourhood, having as study object the already consolidated constructions of residential use, intended to demonstrate that the neighbourhood needes specific norms and that the limits established for recognition of Special Areas of Social Interest for the urbanistic legislation of the City of Natal would have to be reviewed and to be brought up to date, once they show occupations like the ones of the reffered neighbourhood. At a first moment, bibliographical revision and elaboration of the theoretical referencial had been made, , to analyze afterwards the urbanistic legislation for the neibourhood of Rocas, that determines relative parameters for the sizes of land lots, coefficients of exploitation, minimum taxes of occupation and retreat. Through a field research in the area, a study on the occupation description was done at first, characterization of the neibourhood through the study of the social-economic aspects, of the existing infrastructure in the place, environmental aspects, morphologic and tipolgic analysis of the neibourhood as a whole. From the grouping of the found characteristics, sub-zones had been delimited, where the real object of study was detached to be analyzed. From the Sub-zoning, a statistic sampling was carried through with the intention to examine which of the urbanistic index is found in the dwellings of that already materialized place. This sampling, of one hundred and eighteen residences, was carried through by measurement of the lots and existing constructions in these places. Through this survey, for each habitacional unit, area of the lot, constructed area, retreats and coefficient of exploitation had been calculated. The comparison between the legislation parameters and the index found in the place reveal an expressive index of urbanistic irregularity and the necessity of special regulation for the Rocas neibourhood due to its specific social-space characteristic

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The Northeast relief was described by the Pediplanation Model. This action discards the theoretical basis of post-Cretaceous tectonic evolution of the landscape. Through this model the Massif Pereiro - MP, Borborema Province, was established as part of the Tablelands Area Residual Sertanejos. The present work aims to establish the post- Cretaceous morphotectonic evolution of the MP by geomorphological and geological mapping using Geographic Information System, Remote Sensing and dating of sediments by Single Aliquot Regenerative-dose (SAR). The MP is contained in the core semi-arid, annual precipitation of 600-800 mm / year. The MP is NE-SW, is limited by Shear Zone Jaguaribe (ZCJ) and Portalegre Shear Zone (ZCPa), the same attitude, and crossed by several other shear zones. These shear zones show evidence of brittle Cenozoic reactivation, mostly as normal faults and shallow crustal level. The Quaternary sedimentation around the MP focuses on fault escarpments in a general pattern cascade, where ages decrease from the summits of the steep foothills. The ages of 51 sediment samples indicate a correlation with global climate following pulses: Last Interestadial-UI, the Last Glacial Maximum - LGM and the transition Pleistocene / Holocene, while the latter focus on 18 of 51 samples dated. This study also finds evidence of a new quaternary basin, here called Merejo Basin. Through these results it is concluded that no evidence of post-Cretaceous tectonic evolution of morphological MP, as their retreat along the fault scarps, invariably following the trend of the shear zones. The erosion of cliffs in large time scale is controlled by weakness zones generated by faults on the other hand the erosion of cliffs in short time, with the formation of deposits and colluvial horizons pedogenizados, has climate control. It was also found that in the study area there is a preponderance of past and current tectonic erosion processes on the morphological evolution