8,446 research outputs found

    Life without the Beach: Projected Sea Level Rise and its Impact on Barrier Islands Along the East Coast, USA

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    As climate change is becoming a global issue, the impact of sea level rise is increasingly becoming a threat to humans, wildlife, infrastructure, and ecosystems. To evaluate the effects of sea level rise on barrier islands and coastal regions, we studied future projections of sea level rise at Ocean City and Assateague Island, Maryland. We hypothesize that the sea levels at Assateague and Ocean City will have different beach profiles, and will show different levels of flooding through the Representative Concentration Pathways (RCP) simulations. We measured beach profiles at four locations, two at Ocean City and two at Assateague Island, to view the current beach profiles and found that Ocean City reveals a smaller average change in elevation compared to Assateague. We also used a LiDAR Digital Elevation Model (DEM) of Ocean City and Assateague Island to run RCP 2.6, RCP 4.5, and RCP 8.5 simulations using GIS to represent the Intergovernmental Panel on Climate Change (IPCC) projected sea level rise for the year 2100. We found that Ocean City has higher predicted percentages of flooded land but smaller areas of flooded land compared to Assateague. These results indicate that significant areas of both Ocean City and Assateague Island will be flooded by 2100 regardless of which RCP simulation might be true. However, it is projected that the RCP 2.6 simulation is an underestimation of potential flooding and the future will more closely resemble the RCP 8.5 simulation if drastic precautions are not taken now. This will severely impact ecosystems, economies, and human life

    Zeroes of primary summand functions on compact solvmanifolds

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    AbstractThe fact that continuous functions in primary summands of the Heisenberg manifold must vanish somewhere was proven by L. Auslander and R. Tolimieri, who deduced from this theorem the classical results on the vanishing of theta functions, as well as important applications to wavelets and radar ambiguity functions. The Heisenberg theorem seemed to depend on the presence of a central character, but the result is here extended to include primary summand functions on all compact nilmanifolds and to three-dimensional compact solvmanifolds which are not n-tori

    The Costs and Legal Implications Facing Implementation of the European Union\u27s Droit de Suite Directive in the United Kingdom

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    In 2001, the European Union passed a directive requiring member countries to implement a droit de suite on the resale of art. A droit de suite is a resale royalty created to benefit visual artists. The purpose of the droit de suite is to allow artists to profit off of their growing reputations; for example, a starving artist who has sold a work for a pittance may profit (or his heirs may profit) when he has risen in prominence and his work has consequently increased in value. The United Kingdom actively opposed the directive;8 it worried about the effect of the directive on its lucrative art market9 and questioned the usefulness of the droit de suite itself. Nevertheless, the directive was passed and the United Kingdom must implement the directive within the next eight to ten years. This comment will examine the problems the United Kingdom will face when it passes the droit de suite legislation mandated by the European Union\u27s directive

    The Costs and Legal Implications Facing Implementation of the European Union\u27s Droit de Suite Directive in the United Kingdom

    Get PDF
    In 2001, the European Union passed a directive requiring member countries to implement a droit de suite on the resale of art. A droit de suite is a resale royalty created to benefit visual artists. The purpose of the droit de suite is to allow artists to profit off of their growing reputations; for example, a starving artist who has sold a work for a pittance may profit (or his heirs may profit) when he has risen in prominence and his work has consequently increased in value. The United Kingdom actively opposed the directive;8 it worried about the effect of the directive on its lucrative art market9 and questioned the usefulness of the droit de suite itself. Nevertheless, the directive was passed and the United Kingdom must implement the directive within the next eight to ten years. This comment will examine the problems the United Kingdom will face when it passes the droit de suite legislation mandated by the European Union\u27s directive

    Atmospheric transport and deposition of Indonesian volcanic emissions

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    International audienceA regional climate model has been used to study the transport and deposition of sulfur (SO2 and SO42-) and PbCl2 emissions from Indonesian volcanoes. The sensitivity of the atmospheric loss of these trace species to meteorological conditions and their solubility was examined. Two experiments were conducted: 1) volcanic sulfur released as primarily SO2 and subject to transport, deposition, and oxidation to SO42-; and 2) PbCl2 released as an infinitely soluble passive tracer subject to only transport and deposition. The first experiment was used to calculate SO2 loss rates from each active Indonesian volcano producing an annual mean loss rate for all volcanoes of 1.1Ă—10-5 s-1, or an e-folding rate of approximately 1 day. SO2 loss rate was found to vary seasonally, be poorly correlated with wind speed, and uncorrelated with temperature or relative humidity. The variability of SO2 loss rates is found to be correlated with the variability of wind speeds, suggesting that it is much more difficult to establish a "typical'' SO2 loss rate for volcanoes that are exposed to changeable winds. Within an average distance of 70 km away from the active Indonesian volcanoes, 53% of SO2 loss is due to conversion to SO42-, 42% due to dry deposition, and 5% due to lateral transport away from the dominant direction of plume travel. The solubility of volcanic emissions in water is shown to influence their atmospheric transport and deposition. High concentrations of PbCl2 are predicted to be deposited near to the volcanoes while volcanic S travels further away until removal from the atmosphere primarily via the wet deposition of H2SO4. The ratio of the concentration of PbCl2 to SO2 is found to exponentially decay at increasing distance from the volcanoes. The more rapid removal of highly soluble species should be considered when observing SO2 in an aged plume and relating this concentration to other volcanic species. An assumption that the ratio between the concentrations of highly soluble volcanic compounds and SO2 within a plume is equal to that observed in fumarolic gases is reasonable at small distances from the volcanic vent, but will result in an underestimation of the emission flux of highly soluble species

    A full descriptive definition of the BV-integral

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    summary:We present a Cauchy test for the almost derivability of additive functions of bounded BV sets. The test yields a full descriptive definition of a coordinate free Riemann type integral

    Anisotropic splitting of intersubband spin plasmons in quantum wells with bulk and structural inversion asymmetry

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    In semiconductor heterostructures, bulk and structural inversion asymmetry and spin-orbit coupling induce a k-dependent spin splitting of valence and conduction subbands, which can be viewed as being caused by momentum-dependent crystal magnetic fields. This paper studies the influence of these effective magnetic fields on the intersubband spin dynamics in an asymmetric n-type GaAs/AlGaAs quantum well. We calculate the dispersions of intersubband spin plasmons using linear response theory. The so-called D'yakonov-Perel' decoherence mechanism is inactive for collective intersubband excitations, i.e., crystal magnetic fields do not lead to decoherence of spin plasmons. Instead, we predict that the main signature of bulk and structural inversion asymmetry in intersubband spin dynamics is a three-fold, anisotropic splitting of the spin plasmon dispersion. The importance of many-body effects is pointed out, and conditions for experimental observation with inelastic light scattering are discussed.Comment: 8 pages, 6 figure
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