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101.
102.
This paper presents an analysis of nocturnal drainage flows in a mountainous coastal environment where the elevation of the terrain is comparable with the elevation of the marine temperature inversion. The analysis traces the initiation, evolution, and breakup of the drainage flow using acoustic sounder facsimile data and tethered sonde measurements of wind and temperature. Conditions addressed include (1) opposing seabreeze flow ranging from 2 to 8m s-1, (2) aiding flow, and (3) large-scale and drainage-induced subsidence. The effect of deep marine temperature inversions pervades the observations, as seen in deeper, more stratified echo layers, weaker drainage, and delayed destruction of the inversion in the morning.  相似文献   
103.
Ellerman bombs are bright emission features observed in the wings of Hα, usually in the vicinity of magnetic concentrations. Here we show that they can also be detected in the Ca II infrared triplet lines, which are easier to interpret and therefore allow for more detailed diagnostics. We present full Stokes observations of the 849.8 and 854.2 nm lines acquired with the new spectro-polarimeter SPINOR. The data show no significant linear polarization at the level of 3 × 10−4. The circular polarization profiles exhibit measureable signals with a very intricate pattern of peaks. A non-LTE analysis of the spectral profiles emerging from these features reveals the presence of strong downflows (∼10 {km s−1}) in a hot layer between the upper photosphere and the lower chromosphere. Visiting Astronomers, National Solar Observatory, operated by the Association of Universities for Research in Astronomy, Inc. (AURA), under cooperative agreement with the National Science Foundation. The National Center for Atmospheric Research (NCAR) is sponsored by the National Science Foundation, USA.  相似文献   
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Concepts of several experimental configurations for the investigation of magnetized jets and their interaction with magnetized environments are presented. In the planned experiments, the plasma jets will be created by laser ablation of shaped targets, while magnetic and electric fields with the required configurations will be produced independently by a pulsed power generator. In particular, the recently coupled Terawatt laser Tomcat and Terawatt pulsed power generator Zebra will be used for experiments.  相似文献   
107.
Energy and climate policies may have significant economy-wide impacts, which are regularly assessed based on quantitative energy-environment-economy models. These tend to vary in their conclusions on the scale and direction of the likely macroeconomic impacts of a low-carbon transition. This paper traces the characteristic discrepancies in models’ outcomes to their origins in different macro-economic theories, most importantly their treatment of technological innovation and finance. We comprehensively analyse the relevant branches of macro-innovation theory and group them into two classes: ‘Equilibrium’ and ‘Non-equilibrium’. While both approaches are rigorous and self-consistent, they frequently yield opposite conclusions for the economic impacts of low-carbon policies. We show that model outcomes are mainly determined by their representations of monetary and finance dimensions, and their interactions with investment, innovation and technological change. Improving these in all modelling approaches is crucial for strengthening the evidence base for policy making and gaining a more consistent picture of the macroeconomic impacts of achieving emissions reductions objectives. The paper contributes towards the ongoing effort of enhancing the transparency and understanding of sophisticated model mechanisms applied to energy and climate policy analysis. It helps tackle the overall ‘black box’ critique, much-cited in policy circles and elsewhere.

Key policy insights

  • Quantitative models commissioned by policy-makers to assess the macroeconomic impacts of climate policy generate contradictory outcomes and interpretations.

  • The source of the differences in model outcomes originates primarily from assumptions on the workings of the financial sector and the nature of money, and of how these interact with processes of low-carbon energy innovation and technological change.

  • Representations of innovation and technological change are incomplete in energy-economy-environment models, leading to limitations in the assessment of the impacts of climate-related policies.

  • All modelling studies should state clearly their underpinning theoretical school and their treatment of finance and innovation.

  • A strong recommendation is given for modellers of energy-economy systems to improve their representations of money and finance.

  相似文献   
108.
Natural Hazards - Emergency evacuation is the immediate escape of people away from a place of an imminent threat to a place of safety. The ability of the households to evacuate is a crucial...  相似文献   
109.
We select 947 star-forming galaxies from SDSS-DR7 with [O III]λ4363emission lines detected at a signal-to-noise ratio larger than 5σ. Their electron temperatures and direct oxygen abundances are then determined. We compare the results from different methods. t2, the electron temperature in the low ionization region, estimated from t3, that in the high ionization region, is compared using three analysis relations between t2- t3. These show obvious differences, which result in some different ionic oxygen abundances. The results of t3, t2, O++/H+and O+/H+derived by using methods from IRAF and literature are also compared. The ionic abundances O++/H+are higher than O+/H+for most cases. The different oxygen abundances derived from Teand the strong-line ratios show a clear discrepancy, which is more obvious following increasing stellar mass and strong-line ratio R23. The sample of galaxies from SDSS with detected [O III]λ4363 have lower metallicites and higher star formation rates, so they may not be typical representatives of the whole population of galaxies. Adopting data objects from Andrews Martini, Liang et al. and Lee et al. data, we derive new relations of stellar mass and metallicity for star-forming galaxies in a much wider stellar mass range: from 106 M to 1011 M.  相似文献   
110.
Following several recommendations presented by the Astrophysics Decadal Survey 2010 centered around the need to define “a future ultraviolet-optical space capability”, on 2012 May 25, NASA issued a Request for Information (RFI) seeking persuasive ultraviolet (UV) and visible wavelength astrophysics science investigations. The goal was to develop a cohesive and compelling set of science objectives that motivate and support the development of the next generation of ultraviolet/visible space astrophysics missions. Responses were due on 10 August 2012 when 34 submissions were received addressing a number of potential science drivers. A UV/visible Mission RFI Workshop was held on 2012 September 20 where each of these submissions was summarized and discussed in the context of each other. We present a scientific analysis of these submissions and presentations and the pursuant measurement capability needs, which could influence ultraviolet/visible technology development plans for the rest of this decade. We also describe the process and requirements leading to the inception of this community RFI, subsequent workshop and the expected evolution of these ideas and concepts for the remainder of this decade.  相似文献   
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