109 research outputs found
The impacts of El Niño on the observed sea ice budget of West Antarctica
We assess the impact of El Niño-induced wind changes on seasonal West Antarctic sea ice concentrations using reanalysis data and sea ice observations. A novel ice budget analysis reveals that in autumn a previously identified east-west dipole of sea ice concentration anomalies is formed by dynamic and thermodynamic processes in response to El Niño-generated circulation changes. The dipole features decreased (increased) concentration in the Ross Sea (Amundsen and Bellingshausen Seas). Thermodynamic processes and feedback make a substantial contribution to ice anomalies in all seasons. The eastward propagation of this anomaly is partly driven by mean sea ice drift rather than anomalous winds. Our results demonstrate that linkages between sea ice anomalies and atmospheric variability are highly nonlocal in space and time. Therefore, we assert that caution should be applied when interpreting the results of studies that attribute sea ice changes without accounting for such temporally and spatially remote linkages
Assessing recent trends in high-latitude Southern Hemisphere surface climate
Understanding the causes of recent climatic trends and variability in the high-latitude Southern Hemisphere is hampered by a short instrumental record. Here, we analyse recent atmosphere, surface ocean and sea-ice observations in this region and assess their trends in the context of palaeoclimate records and climate model simulations. Over the 36-year satellite era, significant linear trends in annual mean sea-ice extent, surface temperature and sea-level pressure are superimposed on large interannual to decadal variability. However, most observed trends are not unusual when compared with Antarctic paleoclimate records of the past two centuries. With the exception of the positive trend in the Southern Annular Mode, climate model simulations that include anthropogenic forcing are not compatible with the observed trends. This suggests that natural variability likely overwhelms the forced response in the observations, but the models may not fully represent this natural variability or may overestimate the magnitude of the forced response
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The new Victorians? Celebrity charity and the demise of the welfare state
This article asks whether the expansion of celebrity involvement in charitable and humanitarian issues in Northern Europe and the US might be a comparable historical phenomenon with the philanthropic endeavours of prominent nineteenth-century persons. The article notes that the conspicuous nature of star philanthropy in both Victorian times and the present is fairly dramatic in comparison with that of the mid twentieth century, when the welfare state and the New Deal were at their peak: a welfare-oriented era which, to some, now increasingly looks like a âhistorical blipâ. It asks whether the rise of contemporary celebrity involvement in charity can therefore be explained in terms of the contemporary political conjuncture, inasmuch as celebrities could be understood as individuals with large amounts of private capital seeking to intervene in â and gain forms of power through â involvement in humanitarian and charitable causes that might have formerly been the job of the state. Can celebrity involvement in charity be explained in these terms? Does the marriage of celebrity and charity today take a neoliberal form, one that parallels the liberal form of nineteenth-century interventions, bequests and donations? What might the key differences between forms of spectacular âphilanthrocapitalismâ in these eras (particularly the contemporary insistence on the confessional and intimate modes of address) reveal about its workings, its internal traditions and about the specificity of our own age? This article draws on contemporary media discourse, debate in the voluntary sector, historical scholarship and Foucaultâs distinctions between liberalism and neoliberalism to argue that whereas âcelanthropyâ in the Victorian period eventually came to contribute to the welfare state, today it is more involved in privatising and dismantling it
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