762 resultados para Rowan, Margaret Rittenhouse


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The importance of aerosol emissions for near term climate projections is investigated by analysing simulations with the HadGEM2-ES model under two different emissions scenarios: RCP2.6 and RCP4.5. It is shown that the near term warming projected under RCP2.6 is greater than under RCP4.5, even though the greenhouse gas forcing is lower. Rapid and substantial reductions in sulphate aerosol emissions due to a reduction of coal burning in RCP2.6 lead to a reduction in the negative shortwave forcing due to aerosol direct and indirect effects. Indirect effects play an important role over the northern hemisphere oceans, especially the subtropical northeastern Pacific where an anomaly of 5-10\,Wm$^{-2}$ develops. The pattern of surface temperature change is consistent with the expected response to this surface radiation anomaly, whilst also exhibiting features that reflect redistribution of energy, and feedbacks, within the climate system. These results demonstrate the importance of aerosol emissions as a key source of uncertainty in near term projections of global and regional climate.

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A thermoresponsive, supramolecular nanocomposite has been prepared by the addition of pyrenyl functionalized gold nanoparticles (AuNPs) to a polydiimide that contains receptor residues designed to form defined complexes with pyrene. The novel pyrenyl-functionalized AuNPs (P-AuNPs) were characterized by transmission electron microscopy, with surface functionalization confirmed by infrared and UV–visible spectroscopic analyses. Mixing solutions of the P-AuNPs and a π-electron-deficient polydiimide resulted in the formation of electronically complementary, chain-folded and π–π-stacked complexes, so affording a new supramolecular nanocomposite network which precipitated from solution. The P-AuNPs bind to the polydiimide via π–π stacking interactions to create supramolecular cross-links. UV–visible spectroscopic analysis confirmed the thermally reversible nature of the complexation process, and transmission electron microscopy (TEM), infrared spectroscopy (IR), and differential scanning calorimetry (DSC) were used to characterize the supramolecular-nanocomposite material. The supramolecular polymer network is insoluble at room temperature, yet may be dissolved at temperatures above 60 °C. The thermal reversibility of this system is maintained over five heat/cool cycles without diminishment of the network characteristics. In contrast to the individual components, the nanocomposite formed self-supporting films, demonstrating the benefit of the supramolecular network in terms of mechanical properties. Control experiments probing the interactions between a model diimide compound that can also form a π-stacked complex with the π-electron rich pyrene units on P-AuNPs showed that, while complexation was readily apparent, precipitation did not occur because a supramolecular cross-linked network system could not be formed with this system.

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This article provides time series data on the medieval market in freehold land, including the changing social composition of freeholders, level of market activity, size and complexity of landholdings, and shifts in the market value of land. These are subjects hitherto largely ignored due, in part, to the disparate nature of the evidence. It argues that feet of fines, despite archival limitations, if employed with care and an understanding of the underlying changes in the common law of real property, are capable of providing quantifiable evidence spanning hundreds of years and comparable across large areas of England.

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European climate exhibits variability on a wide range of timescales. Understanding the nature and drivers of this variability is an essential step in developing robust climate predictions and risk assessments. The Atlantic Ocean has been suggested as an important driver of variability in European climate on decadal timescales1, but the importance of this influence in recent decades has been unclear, partly because of difficulties in separating the influence of the Atlantic Ocean from other contributions, for example, from the tropical Pacific Ocean and the stratosphere. Here we analyse four data sets derived from observations to show that, during the 1990s, there was a substantial shift in European climate towards a pattern characterized by anomalously wet summers in northern Europe, and hot, dry, summers in southern Europe, with related shifts in spring and autumn. These changes in climate coincided with a substantial warming of the North Atlantic Ocean, towards a state last seen in the 1950s. The patterns of European climate change in the 1990s are consistent with earlier changes attributed to the influence of the North Atlantic Ocean, and provide compelling evidence that the Atlantic Ocean was the key driver. Our results suggest that the recent pattern of anomalies in European climate will persist as long as the North Atlantic Ocean remains anomalously warm.

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The efficiency with which the oceans take up heat has a significant influence on the rate of global warming. Warming of the ocean above 700 m over the past few decades has been well documented. However, most of the ocean lies below 700 m. Here we analyse observations of heat uptake into the deep North Atlantic. We find that the extratropical North Atlantic as a whole warmed by 1.45±0.5×1022 J between 1955 and 2005, but Lower North Atlantic Deep Water cooled, most likely as an adjustment from an early twentieth-century warm period. In contrast, the heat content of Upper North Atlantic Deep Water exhibited strong decadal variability. We demonstrate and quantify the importance of density-compensated temperature anomalies for long-term heat uptake into the deep North Atlantic. These anomalies form in the subpolar gyre and propagate equatorwards. High salinity in the subpolar gyre is a key requirement for this mechanism. In the past 50 years, suitable conditions have occurred only twice: first during the 1960s and again during the past decade. We conclude that heat uptake through density-compensated temperature anomalies will contribute to deep ocean heat uptake in the near term. In the longer term, the importance of this mechanism will be determined by competition between the multiple processes that influence subpolar gyre salinity in a changing climate.

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In 1938, Yugoslav sculptor Oscar Nemon arrived in Britain, having fled the Nazi invasion of Brussels, where he was living with Magritte. He was part of the European avant-garde that came to the UK as a refugee. Shortly thereafter, Nemon proposed a bold architectural plan to construct a temple of universal ethics in London and was in correspondence over this with central figures in Britain. After the war, he became know for his portrayal of figures like Churchil, culminating in a bust of Margaret Thatcher that is currently at the Tory HQ. Shown at Castlefield Gallery in 2013-2014, Radical Conservatism was an exhibition that explored the space between these two moments and asked whether these two terms are really antithetical. In the British context in particular, where the European avant-garde never really took hold, a kind of reactionary modernism has always defined a culture wary of revolution. But today more than ever, with the left increasingly holding on to the past of the welfare state as an ideal, and the right quietly revolutionising our world through neoliberal reforms, the paradigms of radicalism and conservatism need to be redefined. Can conservatism be seen as a radical position in itself? If art is defined by a movement towards the new - could 'holding on to the past' stubbornly be seen as a critical position, now that neo-liberalism has forced a far more radical shift in politics than the left has managed in a long time? Curated by Pil and Galia Kollectiv, featuring work by Chris Evans, IRWIN, Pil and Galia Kollectiv, Joseph Lewis, Patrick Moran, Oscar Nemon and Public Movement and a symposium with contributions from Professor Alun Rowlands and Robert Garnett.

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This article reports on research which identified perceptions of reading and the teaching of reading held by trainee teachers and the impact on my provision as a teacher educator. It found that students’ past and present experiences of learning to read and being a reader influenced their perceptions of what reading is and of what it means to teach reading. As a teacher educator, I am not able to give students long experience of seeing children becoming readers, but I am able to give them richer experiences of reading in personally and culturally relevant contexts. This has implications for the nature of subject knowledge required by a student teacher of reading and the curriculum and practice of teacher education.

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Drought is a global problem that has far-reaching impacts and especially 47 on vulnerable populations in developing regions. This paper highlights the need for a Global Drought Early Warning System (GDEWS), the elements that constitute its underlying framework (GDEWF) and the recent progress made towards its development. Many countries lack drought monitoring systems, as well as the capacity to respond via appropriate political, institutional and technological frameworks, and these have inhibited the development of integrated drought management plans or early warning systems. The GDEWS will provide a source of drought tools and products via the GDEWF for countries and regions to develop tailored drought early warning systems for their own users. A key goal of a GDEWS is to maximize the lead time for early warning, allowing drought managers and disaster coordinators more time to put mitigation measures in place to reduce the vulnerability to drought. To address this, the GDEWF will take both a top-down approach to provide global real-time drought monitoring and seasonal forecasting, and a bottom-up approach that builds upon existing national and regional systems to provide continental to global coverage. A number of challenges must be overcome, however, before a GDEWS can become a reality, including the lack of in-situ measurement networks and modest seasonal forecast skill in many regions, and the lack of infrastructure to translate data into useable information. A set of international partners, through a series of recent workshops and evolving collaborations, has made progress towards meeting these challenges and developing a global system.

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Aleks Sierz in his important survey of mid 1990s drama has identified the plays of Sarah Kane as exemplars of what he terms ‘In-Yer Face’ theatre. Sierz argues that Kane and her contemporaries such as Mark Ravenhill and Judy Upton represent a break with the ideological concerns of the previous generation of playwrights such as Doug Lucie and Stephen Lowe, whose work was shaped through recognizable political concerns, often in direct opposition to Thatcherism. In contrast Sarah Kane and her generation have frequently been seen as literary embodiments of ‘Thatcher’s Children’, whereby following the fall of the Berlin Wall and the inertia of the Major years, their drama eschews a recognizable political position, and seems more preoccupied with the plight of individuals cut adrift from society. In the case of Sarah Kane her frequently quoted statement, ‘I have no responsibility as a woman writer because I don’t believe there’s such a thing’, has compounded this perception. Moreover, its dogmatism also echoes the infamous comments attributed to Mrs Thatcher regarding the role of the individual to society. However, this article seeks to reassess Kane’s position as a woman writer and will argue that her drama is positioned somewhere between the female playwrights who emerged after 1979 such as Sarah Daniels, Timberlake Wertenbaker and Clare McIntyre, whose drama was distinguished by overtly feminist concerns, and its subsequent breakdown, best exemplified by the brief cultural moment associated with the newly elected Blair government known as ‘Cool Britannia’. Drawing on a variety of sources, including Kane’s unpublished monologues, written while she was a student just after Mrs Thatcher left office, this paper will argue that far from being an exponent of post-feminism, Kane’s drama frequently revisits and is influenced by the generation of dramatists whose work was forged out the sharp ideological positions that characterized the 1980s and a direct consequence of Thatcherism.

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Identifying the prime drivers of the twentieth-century multidecadal variability in the Atlantic Ocean is crucial for predicting how the Atlantic will evolve in the coming decades and the resulting broad impacts on weather and precipitation patterns around the globe. Recently, Booth et al. showed that the Hadley Centre Global Environmental Model, version 2, Earth system configuration (HadGEM2-ES) closely reproduces the observed multidecadal variations of area-averaged North Atlantic sea surface temperature in the twentieth century. The multidecadal variations simulated in HadGEM2-ES are primarily driven by aerosol indirect effects that modify net surface shortwave radiation. On the basis of these results, Booth et al. concluded that aerosols are a prime driver of twentieth-century North Atlantic climate variability. However, here it is shown that there are major discrepancies between the HadGEM2-ES simulations and observations in the North Atlantic upper-ocean heat content, in the spatial pattern of multidecadal SST changes within and outside the North Atlantic, and in the subpolar North Atlantic sea surface salinity. These discrepancies may be strongly influenced by, and indeed in large part caused by, aerosol effects. It is also shown that the aerosol effects simulated in HadGEM2-ES cannot account for the observed anticorrelation between detrended multidecadal surface and subsurface temperature variations in the tropical North Atlantic. These discrepancies cast considerable doubt on the claim that aerosol forcing drives the bulk of this multidecadal variability.

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This paper provides an update on research in the relatively new and fast-moving field of decadal climate prediction, and addresses the use of decadal climate predictions not only for potential users of such information but also for improving our understanding of processes in the climate system. External forcing influences the predictions throughout, but their contributions to predictive skill become dominant after most of the improved skill from initialization with observations vanishes after about six to nine years. Recent multi-model results suggest that there is relatively more decadal predictive skill in the North Atlantic, western Pacific, and Indian Oceans than in other regions of the world oceans. Aspects of decadal variability of SSTs, like the mid-1970s shift in the Pacific, the mid-1990s shift in the northern North Atlantic and western Pacific, and the early-2000s hiatus, are better represented in initialized hindcasts compared to uninitialized simulations. There is evidence of higher skill in initialized multi-model ensemble decadal hindcasts than in single model results, with multi-model initialized predictions for near term climate showing somewhat less global warming than uninitialized simulations. Some decadal hindcasts have shown statistically reliable predictions of surface temperature over various land and ocean regions for lead times of up to 6-9 years, but this needs to be investigated in a wider set of models. As in the early days of El Niño-Southern Oscillation (ENSO) prediction, improvements to models will reduce the need for bias adjustment, and increase the reliability, and thus usefulness, of decadal climate predictions in the future.