33 resultados para Art, Modern -- 21st century


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We investigate the effects of a recently proposed 21st century Dalton minimum like decline of solar activity on the evolution of Earth's climate and ozone layer. Three sets of two member ensemble simulations, radiatively forced by a midlevel emission scenario (Intergovernmental Panel on Climate Change RCP4.5), are performed with the atmosphere-ocean chemistry-climate model AOCCM SOCOL3-MPIOM, one with constant solar activity, the other two with reduced solar activity and different strength of the solar irradiance forcing. A future grand solar minimum will reduce the global mean surface warming of 2 K between 1986–2005 and 2081–2100 by 0.2 to 0.3 K. Furthermore, the decrease in solar UV radiation leads to a significant delay of stratospheric ozone recovery by 10 years and longer. Therefore, the effects of a solar activity minimum, should it occur, may interfere with international efforts for the protection of global climate and the ozone layer.

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The conservation of large carnivores is a formidable challenge for biodiversity conservation. Using a data set on the past and current status of brown bears (Ursus arctos), Eurasian lynx (Lynx lynx), gray wolves (Canis lupus), and wolverines (Gulo gulo) in European countries, we show that roughly one-third of mainland Europe hosts at least one large carnivore species, with stable or increasing abundance in most cases in 21st-century records. The reasons for this overall conservation success include protective legislation, supportive public opinion, and a variety of practices making coexistence between large carnivores and people possible. The European situation reveals that large carnivores and people can share the same landscape.

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It is a well-documented fact that the Middle Ages have had a long history of instrumentalisation by nationalisms. 19th-century Eu¬rope in particular witnessed an origins craze during the process of nation-building. In the post-Shoah, post-modern West, on the other hand, we might expect this kind of medievalist master nar¬rative to have been consigned to the dustbin of history. And yet, as nationalism surges again in Europe, negotiations of national identi¬ties in medieval dress seem to have become fashionable once more. In order to come to terms with the fragmented and often contradictory presence of the Middle Ages in these discourses of national identity, I propose we consider medievalism a utilitarian product of the cultural memory. Rather than representing any ‘real’ Middle Ages, then, medievalism tailors available knowledge of the medieval past to the diverse social needs and ideologies of the present. This paper looks at a selection of Scottish examples of present-day medievalism in an attempt to investigate, in particular, the place of the medieval Wars of Scottish Independence in contemporary negotiations of ‘Scottishness’. Both the relationships envisioned between self and other and the role played by ‘the land’ in these cultural, social and political instances of national introspection offer starting points for critical inquiry. Moreover, the analysis of a scholarly intervention in the run-up to the 2014 Scottish independence referendum indicates an intriguing dialogue of academic and non-academic voices in the context of Scottish medievalist cultural memory. We thus find a wide array of uses of the Scottish Middle Ages, some of which feed into the burgeoning nationalism of recent years, while others offer more pensive and ambivalent answers to the question of what it means to be Scottish in the 21st century.

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Radiocarbon production, solar activity, total solar irradiance (TSI) and solar-induced climate change are reconstructed for the Holocene (10 to 0 kyr BP), and TSI is predicted for the next centuries. The IntCal09/SHCal04 radiocarbon and ice core CO2 records, reconstructions of the geomagnetic dipole, and instrumental data of solar activity are applied in the Bern3D-LPJ, a fully featured Earth system model of intermediate complexity including a 3-D dynamic ocean, ocean sediments, and a dynamic vegetation model, and in formulations linking radiocarbon production, the solar modulation potential, and TSI. Uncertainties are assessed using Monte Carlo simulations and bounding scenarios. Transient climate simulations span the past 21 thousand years, thereby considering the time lags and uncertainties associated with the last glacial termination. Our carbon-cycle-based modern estimate of radiocarbon production of 1.7 atoms cm−2 s−1 is lower than previously reported for the cosmogenic nuclide production model by Masarik and Beer (2009) and is more in-line with Kovaltsov et al. (2012). In contrast to earlier studies, periods of high solar activity were quite common not only in recent millennia, but throughout the Holocene. Notable deviations compared to earlier reconstructions are also found on decadal to centennial timescales. We show that earlier Holocene reconstructions, not accounting for the interhemispheric gradients in radiocarbon, are biased low. Solar activity is during 28% of the time higher than the modern average (650 MeV), but the absolute values remain weakly constrained due to uncertainties in the normalisation of the solar modulation to instrumental data. A recently published solar activity–TSI relationship yields small changes in Holocene TSI of the order of 1 W m−2 with a Maunder Minimum irradiance reduction of 0.85 ± 0.16 W m−2. Related solar-induced variations in global mean surface air temperature are simulated to be within 0.1 K. Autoregressive modelling suggests a declining trend of solar activity in the 21st century towards average Holocene conditions.