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21.
In the annular or total eclipses of 3 October 2005, 29 March 2006, 22 September 2006, and 1 August 2008, observational campaigns were organized to record the phenomenon of Baily’s beads. These campaigns were internationally coordinated through the International Occultation Timing Association (IOTA) at both its American and European sections. From the stations in the northern and southern zones of grazing eclipse, the eclipses have been recorded on video. Afterward, as many beads as possible have been identified by analyzing the video data of each observing station. The atlas presented in this paper includes 598 data points, obtained by 23 observers operating at 28 different observing stations. The atlas lists the geographic positions of the observing stations and the observed time instants of disappearance or reappearance of beads, identified by an angle measured relative to the Moon’s axis of rotation. The atlas will serve as a basis for determining the solar diameter. Electronic Supplementary Material  The online version of this article () contains supplementary material, which is available to authorized users.  相似文献   
22.
Leigh Schwartz 《GeoJournal》2009,74(3):265-274
As geographers begin investigating the imaginative geographies of media spaces, attention is drawn to the landscapes of interactive media. The virtual environments of video games continue to grow in complexity and use, and questions remain as to the experience of the users of the designed environments. Focusing specifically on messages and metaphors in written representations, this paper investigates the changing experience of gamers through time and place by examining the Suikoden fantasy series. Beginning with the adaptation of the Chinese classic Shui Hu Zhuan into Suikoden in 1996, continuing to the release of Suikoden V 10 years later, the virtual environments of the Suikoden series are embedded with mythological and cultural messages about Self and Other. This paper utilizes visual and textual analysis to examine these changing representations over time and place in terms of the experience of these ideological messages by the players of this series.  相似文献   
23.
Pressure–Temperature–time (P–Tt) estimates of the syn‐kinematic strain at the peak‐pressure conditions reached during shallow underthrusting of the Briançonnais Zone in the Alpine subduction zone was made by thermodynamic modelling and 40Ar/39Ar dating in the Plan‐de‐Phasy unit (SE of the Pelvoux Massif, Western Alps). The dated phengite minerals crystallized syn‐kinematically in a shear zone indicating top‐to‐the‐N motion. By combining X‐ray mapping with multi‐equilibrium calculations, we estimate the phengite crystallization conditions at 270 ± 50 °C and 8.1 ± 2 kbar at an age of 45.9 ± 1.1 Ma. Combining this P–Tt estimate with data from the literature allows us to constrain the timing and geometry of Alpine continental subduction. We propose that the Briançonnais units were scalped on top of the slab during ongoing continental subduction and exhumed continuously until collision.  相似文献   
24.
In 2015, Central Europe experienced an unusually warm summer season. For a great majority of climatic stations around Slovakia, it had been the warmest summer ever recorded over their entire instrumental observation period. In this study, we investigate the mortality effects of hot days’ sequences during that particular summer on the Slovak population. In consideration of the range of available mortality data, the position of 2015 is analysed within the years 1996–2015. Over the given 20-year period, the summer heat spells of 2015 were by far the most severe from a meteorological point of view, and clearly the deadliest with the total of almost 540 excess deaths. In terms of impacts, an extraordinary 10-day August heat spell was especially remarkable. The massive lethal effects of heat would have likely been even more serious under normal circumstances, since the number of premature deaths appeared to be partially reduced due to a non-standard mortality pattern in the first quarter of the year. The heat spells of the extremely warm summer of 2015 in Slovakia are notable not just for their short-term response in mortality. It appears that in a combination with the preceding strong influenza season, they subsequently affected mortality conditions in the country in the following months up until the end of the year. The impacts described above were rather different for selected population subgroups (men and women, the elderly). Both separately and as a part of the annual mortality cycle, the 2015 summer heat spells may represent a particularly valuable source of information for public health.  相似文献   
25.
 In the laboratory, computer-assisted image analysis provides an accurate and efficient way to monitor tracer experiments. This paper describes the determination of detailed temporal concentration distributions of tracers in a flow-tank experiment by analyzing photographs of plumes of Rhodamine dye through the glass wall of the tank. The methodology developed for this purpose consists of four steps: (1) digitally scanning black and white negatives obtained from photographs of the flow–tank experiment; (2) calibrating and normalizing each digitized image to a standard optical-density scale by determining the relation between the optical density and pixel value for each image; (3) constructing standard curves relating the concentration in an optical density from five experimental runs with predetermined concentrations (2–97 mg/L); and (4) converting the optical density to concentration. The spatial distribution of concentration for two photographs was determined by applying these calibration and conversion procedures to all pixels of the digitized images. This approach provides an efficient way to study patterns of plume evolution and transport mechanisms. Received, March 1998 Revised, September 1998 Accepted, October 1998  相似文献   
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27.
Observing and Modeling Earth’s Energy Flows   总被引:1,自引:0,他引:1  
This article reviews, from the authors’ perspective, progress in observing and modeling energy flows in Earth’s climate system. Emphasis is placed on the state of understanding of Earth’s energy flows and their susceptibility to perturbations, with particular emphasis on the roles of clouds and aerosols. More accurate measurements of the total solar irradiance and the rate of change of ocean enthalpy help constrain individual components of the energy budget at the top of the atmosphere to within ±2 W m?2. The measurements demonstrate that Earth reflects substantially less solar radiation and emits more terrestrial radiation than was believed even a decade ago. Active remote sensing is helping to constrain the surface energy budget, but new estimates of downwelling surface irradiance that benefit from such methods are proving difficult to reconcile with existing precipitation climatologies. Overall, the energy budget at the surface is much more uncertain than at the top of the atmosphere. A decade of high-precision measurements of the energy budget at the top of the atmosphere is providing new opportunities to track Earth’s energy flows on timescales ranging from days to years, and at very high spatial resolution. The measurements show that the principal limitation in the estimate of secular trends now lies in the natural variability of the Earth system itself. The forcing-feedback-response framework, which has developed to understand how changes in Earth’s energy flows affect surface temperature, is reviewed in light of recent work that shows fast responses (adjustments) of the system are central to the definition of the effective forcing that results from a change in atmospheric composition. In many cases, the adjustment, rather than the characterization of the compositional perturbation (associated, for instance, with changing greenhouse gas concentrations, or aerosol burdens), limits accurate determination of the radiative forcing. Changes in clouds contribute importantly to this adjustment and thus contribute both to uncertainty in estimates of radiative forcing and to uncertainty in the response. Models are indispensable to calculation of the adjustment of the system to a compositional change but are known to be flawed in their representation of clouds. Advances in tracking Earth’s energy flows and compositional changes on daily through decadal timescales are shown to provide both a critical and constructive framework for advancing model development and evaluation.  相似文献   
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The medium-level radioactive waste deposited in the Asse 2 salt mine, Germany, has a total activity of 1.2 × 1015 Bq (1 January 2002). The waste lies in a former mining chamber on the −511 m mining level close to the contact between the Mesozoic country rock and the Zechstein salt dome. The Mesozoic country rock is strongly faulted but the geometry of the fault pattern is incompletely known. Two tectonic cases are considered: a pessimistic case, which assumes that the radioactive source is linked to the surface by a single fault, and an optimistic case, which assumes that the radioactive source is not connected to any fault at all. The potential groundwater contamination by radioactive fluids expelled from the cavity is simulated with the TOUGH2 code for periods of up to 6,000 years, when the potential contamination reaches its greatest vertical extent. Two types of driving forces are considered: convergence of the rock salt surrounding the cavity and generation of H2 gas by the corrosion of iron, steel and other metallic components of the waste at low O2 fugacities. Rock-salt creep has the greatest potential impact, as it leads to a radioactive plume whose 1 Bq/L activity contour rises up to 240 m below the surface in the pessimistic tectonic case. The value of the model for the assessment of the environmental risk is limited. The knowledge of the hydrogeological situation is incomplete and the pessimistic tectonic case may not be pessimistic enough for a realistic worst-case scenario.  相似文献   
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