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Evaluation of moisture sources for the Central European summer flood of May/June 2013 based on regional climate model simulations
Heavy precipitation affected Central Europe in May/June 2013, triggering damaging floods both on the Danube and the Elbe rivers. Based on a modelling approach with COSMO-CLM, moisture fluxes, backward trajectories, cyclone tracks and precipitation fields are evaluated for the relevant time period 30 May–2 June 2013. We identify potential moisture sources and quantify their contribution to the flood event focusing on the Danube basin through sensitivity experiments: Control simulations are performed with undisturbed ERA-Interim boundary conditions, while multiple sensitivity experiments are driven with modified evaporation characteristics over selected marine and land areas. Two relevant cyclones are identified both in reanalysis and in our simulations, which moved counter-clockwise in a retrograde path from Southeastern Europe over Eastern Europe towards the northern slopes of the Alps. The control simulations represent the synoptic evolution of the event reasonably well. The evolution of the precipitation event in the control simulations shows some differences in terms of its spatial and temporal characteristics compared to observations. The main precipitation event can be separated into two phases concerning the moisture sources. Our modelling results provide evidence that the two main sources contributing to the event were the continental evapotranspiration (moisture recycling; both phases) and the North Atlantic Ocean (first phase only). The Mediterranean Sea played only a minor role as a moisture source. This study confirms the importance of continental moisture recycling for heavy precipitation events over Central Europe during the summer half year
Addition of Synthetic Feeding Attractant Increases Catches of Rhagoletis batava Hering and Carpomyia schineri Loew. in Fluorescent Yellow Sticky Traps
The addition of the synthetic Rhagoletis feeding attractant (consisting of ammonium carbonate and ammonium acetate, developed previously for Rhagoletis cerasi L.) to both fluorescent yellow or transparent sticky traps significantly increased catches of the fruit flies Rhagoletis batava Hering (pest of sea buckthorn) and Carpomyia schineri Loew. (pest of rose hips). Traps with lures were detecting the occurrence of both species 1–2 weeks before as compared to traps without lure, and quantitative aspects of the flight could be followed in more detail in traps with lure. Thus in detection and monitoring surveys, where sensitivity of the trap is highly important, the use of traps with synthetic lure added is strongly recommended
Diapirs as the source of the sediment signature in arc lavas
Author Posting. © The Author(s), 2011. This is the author's version of the work. It is posted here by permission of Nature Publishing Group for personal use, not for redistribution. The definitive version was published in Nature Geoscience 4 (2011): 641-646, doi:10.1038/ngeo1214Many arc lavas show evidence for the involvement of subducted sediment in the melting process. There is debate whether this “sediment melt” signature forms at relatively low temperature near the fluid-saturated solidus or at higher temperature beyond the breakdown of trace-element-rich accessory minerals. We present new geochemical data from high- to ultrahigh-pressure rocks that underwent subduction and show no significant depletion of key trace elements in the sediment melt component until peak metamorphic temperatures exceeded ~1050ºC from 2.7 to 5 GPa. These temperatures are higher than for the top of the subducting plate at similar pressures based on thermal models. To address this discrepancy, we use instability calculations for a non-Newtonian buoyant layer in a viscous half-space to show that, in typical subduction zones, solid-state sediment diapirs initiate at temperatures between 500–850ºC. Based on these calculations, we propose that the sediment melt component in arc magmas is produced by high degrees of dehydration melting in buoyant diapirs of metasediment that detach from the slab and rise into the hot mantle wedge. Efficient recycling of sediments into the wedge by this mechanism will alter volatile fluxes into the deep mantle compared to estimates based solely on devolatilization of the slab.Funding for this work was provided by NSF and WHOI’s Deep Ocean Exploration Institute
A detailed geochemical study of island arc crust : the Talkeetna Arc section, south–central Alaska
Author Posting. © The Author, 2006. This is the author's version of the work. It is posted here by permission of Oxford University Press for personal use, not for redistribution. The definitive version was published in Journal of Petrology 47 (2006): 1051-1093, doi:10.1093/petrology/egl002.The Early to Middle Jurassic Talkeetna Arc section exposed in the Chugach Mountains
of south central Alaska is 5-18 km wide and extends for over 150 km. This accreted
island arc includes exposures of upper mantle to volcanic upper crust. The section
comprises six lithologic units, in order of decreasing depth: (1) residual upper mantle
harzburgite (with lesser proportions of dunite); (2) pyroxenite; (3) basal gabbronorite; (4)
lower crustal gabbronorite; (5) mid-crustal plutonic rocks; and (6) volcanic rocks. The
pyroxenites overlie residual mantle peridotite, with some interfingering of the two along
the contact. The basal gabbronorite overlies pyroxenite, again with some interfingering of
the two different units along their contact. Lower crustal gabbronorite (≤10 km thick)
includes abundant rocks with well developed modal layering. The mid-crustal plutonic
rocks include a heterogeneous assemblage of gabbroic rocks, dioritic to tonalitic rocks
(30-40% area), and concentrations of mafic dikes and chilled mafic inclusions. The
volcanic rocks (~7 km thick) range from basalt to rhyolite.
Many of the evolved volcanic compositions are a result of fractional crystallisation
processes whose cumulate products are directly observable in the lower crustal
gabbronorites. For example, Ti and Eu enrichments in lower crustal gabbronorites are
mirrored by Ti and Eu depletions in evolved volcanics. In addition, calculated parental
liquids from ion microprobe analyses of clinopyroxene in lower crustal gabbronorites
indicate that the clinopyroxenes crystallised in equilibrium with liquids whose
compositions were the same as the compositions of volcanic rocks. The compositional
variation of the main series of volcanic and chilled mafic rocks can be modeled through
fractionation of observed phase compositions and phase proportions in lower crustal
gabbronorite (i.e. cumulates).
Primary, mantle-derived melts in the Talkeetna Arc underwent fractionation of
pyroxenite at the base of the crust. Our calculations suggest that more than 25 wt % of the
primary melts crystallised as pyroxenites at the base of the crust. The discrepancy
between the observed proportion of pyroxenites (less than 5% of the arc section) and the
proportion required by crystal fractionation modeling (more than 25%) may be best understood as the result of gravitational instability, with dense ultramafic cumulates,
probably together with dense garnet granulites, foundering into the underlying mantle
during the time when the Talkeetna Arc was magmatically active, or in the initial phases
of slow cooling (and sub-solidus garnet growth) immediately after the cessation of arc
activity.This study was supported by National Science Foundation Grant EAR-9910899
Reconstruction of the Talkeetna intraoceanic arc of Alaska through thermobarometry
Author Posting. © American Geophysical Union, 2008. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research 113 (2008): B03204, doi:10.1029/2007JB005208.The Talkeetna arc is one of two intraoceanic arcs where much of the section from the upper mantle through the volcanic carapace is well exposed. We reconstruct the vertical section of the Talkeetna arc by determining the (re)crystallization pressures at various structural levels. The thermobarometry shows that the tonalites and quartz diorites intruded at ∼5–9 km into a volcanic section estimated from stratigraphy to be 7 km thick. The shallowest, Tazlina and Barnette, gabbros crystallized at ∼17–24 km; the Klanelneechena Klippe crystallized at ∼24–26 km; and the base of the arc crystallized at ∼35 km depth. The arc had a volcanic:plutonic ratio of ∼1:3–1:4. However, many or most of the felsic plutonic rocks may represent crystallized liquids rather than cumulates so that the liquid:cumulate ratio might be 1:2 or larger. The current 5- to 7-km structural thickness of the plutonic section of the arc is ∼15–30% of the original 23- to 28-km thickness. The bulk composition of the original Talkeetna arc section was ∼51–58 wt % SiO2.Funded by NSF EAR-9910899
Feature integration in natural language concepts
Two experiments measured the joint influence of three key sets of semantic features on the frequency with which artifacts (Experiment 1) or plants and creatures (Experiment 2) were categorized in familiar categories. For artifacts, current function outweighed both originally intended function and current appearance. For biological kinds, appearance and behavior, an inner biological function, and appearance and behavior of offspring all had similarly strong effects on categorization. The data were analyzed to determine whether an independent cue model or an interactive model best accounted for how the effects of the three feature sets combined. Feature integration was found to be additive for artifacts but interactive for biological kinds. In keeping with this, membership in contrasting artifact categories tended to be superadditive, indicating overlapping categories, whereas for biological kinds, it was subadditive, indicating conceptual gaps between categories. It is argued that the results underline a key domain difference between artifact and biological concepts
Post-disaster tourism: building resilience through community-led approaches in the aftermath of the 2011 disasters in Japan
Post-disaster tourism is often perceived as a form of Dark Tourism associated with death, loss and destruction. In Japan, the term Dark Tourism has gained prominence following the 2011 Great East Japan Earthquake and Tsunami. This paper focuses on a community-led approach to post-disaster tourism development, initiated in the coastal area of Minamisanriku and labelled by the locals Blue Tourism. From its inception Blue Tourism incorporated non-dark activities which concentrated on the beauty of nature, social and environmental sustainability and the development of an enriched tourist experience. Its co-creational ethos helped transform some of the negative narratives of loss associated with Dark Tourism into positive accounts of communal renewal and hope. The paper highlights the limitations of Dark Tourism to post-disaster recovery and contributes new insights to the community-based tourism literature. We argue that Blue Tourism is not a type of Dark Tourism but a form of resilience which builds around local place-based practices and traditional community knowledge. Consequently, it is capable of achieving sustainable disaster recovery and tourist satisfaction simultaneously
Adsorption of CO on a Platinum (111) surface - a study within a four-component relativistic density functional approach
We report on results of a theoretical study of the adsorption process of a
single carbon oxide molecule on a Platinum (111) surface. A four-component
relativistic density functional method was applied to account for a proper
description of the strong relativistic effects. A limited number of atoms in
the framework of a cluster approach is used to describe the surface. Different
adsorption sites are investigated. We found that CO is preferably adsorbed at
the top position.Comment: 23 Pages with 4 figure
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