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61.
Active regions that are sources of microwave solar emission should appear displaced in latitude relative to the associated optical feature and from this displacement it should be possible to deduce the height. Although the displacement is only about one-third of a min of arc at the most, it was found possible, in an investigation based on 1264 cases in 1970, to obtain a height with a precision as good as or better than has generally been achieved in previous studies based on the rate of motion in longitude. This success could be due to the possibility of using large quantities of data or to tolerance of the method to both terrestrial atmospheric refraction and proper motion in heliographic longitude. The result obtained for 1970 was 18000 ± 5000 km (standard deviation). Application of the latitude method at other wavelengths would be desirable. 相似文献
62.
Using data sets assembled within the WMO Solid Precipitation Measurement Intercomparison, the paper deals with the wind related losses in national methods of solid precipitation measurement. Fourteen different types of precipitation gauges are included in the Harzgerode/GDR intercomparison field. Initial results of the comparisons between the Valdai double fence reference method and the other gauges in terms of dependence on wind speed and type of precipitation are presented. These results reveal that the national unsheltered HELLMANN gauge catches only 24 per cent to 70 per cent of the daily totals of solid precipitation as compared with the reference gauge. Results of the analysis of monthly totals and individual events reveal a similar dependence of gauge deficiencies on wind speed and type of precipitation. Case studies of single snow falls and the wind field conditions around and within the double fence reference are also described. 相似文献
63.
Luminescence dating of Middle Pleistocene proglacial deposits from northern Switzerland: methodological aspects and stratigraphical conclusions
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Sally E. Lowick Marius W. Buechi Dorian Gaar Hans R. Graf Frank Preusser 《Boreas: An International Journal of Quaternary Research》2015,44(3):459-482
Optically stimulated luminescence (OSL) dating was applied to proglacial deposits from the Klettgau Valley in northern Switzerland, which is understood to record several phases of glaciation prior to the Last Interglacial. The aim was to provide an independent chronology for the different sedimentary units to understand better the complex depositional history of the region. This time range requires care when assessing the reliability of the luminescence protocols applied. Equivalent doses for fine‐ and coarse‐grain quartz remained below 300 Gy, while dose response curves for both fractions continued to display growth above 500 Gy. Dose recovery tests confirmed the ability of the single aliquot regenerative (SAR) protocol to recover laboratory doses of a similar size to burial doses, and isothermal decay measurements confirmed the stability of the quartz signal. Having passed rigorous testing criteria, quartz OSL ages of up to ~200 ka were considered reliable but significantly underestimated expected ages and prompt a reconsideration of earlier interpretations of the stratigraphy for this site. Rather than representing three separate glaciations, quartz luminescence ages instead suggest that these deposits record up to four independent ice advances during Marine Isotope Stage 6. For both single grain and single aliquot feldspar dating, it was not possible to separate the conflicting influences of anomalous fading and partial bleaching. However, uncorrected feldspar central age model ages were found to be in reasonable agreement with quartz age estimates, and suggest that feldspar ages may still offer useful additional information in this region. 相似文献
64.
Wolfram Joerss 《Climatic change》2014,124(3):605-616
This paper presents the application of a Monte-Carlo simulation for assessing the uncertainties of German 2005 emissions of particulate matter (PM10 & PM2.5) and aerosol precursors (SO2, NOx, NH3 and NMVOC) carried out in the PAREST (PArticle REduction STrategies) research project. For the uncertainty analysis the German Federal Environment Agency’s emission inventory was amended and integrated with a model on the disaggregation of energy balance data. A series of algorithms was developed in order to make efficient and pragmatic use of available literature and expert judgement data for uncertainties of emission model input data. The inventories for PM10 (95 %-confidence interval: ?16 %/+23 %), PM2.5 (?15 %/+19 %) and NOx (?10 %/+23 %) appear most uncertain, while the inventories for SO2 (?9 %/+9 %), NMVOC (?10 %/+12 %) and NH3 (?13 %/+13 %) show a higher accuracy. The source categories adding the most relevant contributions to overall uncertainty vary across the pollutants and comprise agriculture, mobile machinery in agriculture and forestry, construction sites, small businesses/carpentries, cigarette smoke and fireworks, road traffic, solvent use and stationary combustion. The PAREST results on relative uncertainties have been quoted in the German Informative Inventory Reports since 2012. A comparison shows that the PAREST results for Germany are within the range of (for NH3: close below) other European countries’ results on air pollutant inventory uncertainties as reported in the 2013 Informative Inventory Reports. 相似文献
65.
A new type of coordinates suitable to describe mass outflow out of coronal holes assuming symmetry under the icosahedral group is introduced. 相似文献
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68.
In this article we present different aspects of AGN studies demonstrating the importance of the UV spectral range. Most important diagnostic lines for studying the general physical conditions as well as the metalicities in the central broad line region in AGN are emitted in the UV. The UV/FUV continuum in AGN excites not only the emission lines in the immediate surrounding but it is responsible for the ionization of the intergalactic medium in the early stages of the universe. Variability studies of the emission line profiles of AGN in the UV give us information on the structure and kinematics of the immediate surrounding of the central supermassive black hole as well as on its mass itself. 相似文献
69.
Multiple Quaternary erosion and infill cycles in overdeepened basins of the northern Alpine foreland
Marius W. Buechi Hans Rudolf Graf Peter Haldimann Sally E. Lowick Flavio S. Anselmetti 《Swiss Journal of Geoscience》2018,111(1-2):133-167
The cumulative effect of repeated extensive glaciations represents a poorly constrained component in the understanding of landscape evolution in mid-latitude mountain ranges such as the Alps. Timing, extent, and paleo-climatic conditions of these glaciations are generally poorly understood due to the often-fragmentary character of terrestrial Quaternary records. In this context, the sedimentary infills of subglacial basins may serve as important archives to complement the Quaternary stratigraphy over several glacial–interglacial cycles. In this study, sedimentary facies, valley-fill architecture, and luminescence dating are used to describe nine erosional and depositional cycles (Formations A–I) in the Lower Glatt valley, northern Switzerland. These cycles can be related to the ‘Birrfeld’ Glaciation (~ MIS2), the ‘Beringen’ Glaciation (~ MIS6), and up to three earlier Middle Pleistocene glaciations that can be tentatively correlated to the regional glaciation history. Evidence suggests that deep bedrock trough incision and/or partial re-excavation last occurred mainly during the ‘Beringen’ and ‘Habsburg’ Glaciations. Second-order, ‘inlaid’ glacial basins document separate glacier re-advances during the Beringen Glaciation. The arrangement of subglacial basins in the Glatt valley with different sub-parallel or bifurcating bedrock troughs, re-excavated segments, and inlaid basins document changes in the magnitude and the spatial focus of subglacial erosion over time. The Glatt valley may thus serve as a key example for the glacial landscape evolution in many other repeatedly glaciated forelands. 相似文献
70.
Functional diversity, e.g. based on feeding types, is frequently used for assessment procedures. By using Trichoptera genera Potamophylax and Melampophylax as examples, we demonstrate that functional diversity, based on mandible morphology, is low in the former, but high in the latter. When using functional feeding types for assessment procedures, this strictly questions identification at higher than species level and underlines the importance of providing taxonomic information by describing hitherto unknown larvae.Based on mandible morphology, the close species pair Potamophylax haidukorum and P. winneguthi, both endemics of the Dinaric Western Balkan, are omnivorous shredders, a character shared with all other known larvae of genus Potamophylax. In existing keys, P. haidukorum and P. winneguthi may be separated from morphologically close species (e.g. Allogamus spp., Micropterna spp., Potamophylax spp., Leptotaulius gracilis Schmid and Parachiona picicornis (Pictet)) by the lack of a large posterior sclerite at the lateral protuberance, by the lack of additional face setae at mid and hind femora, by the absence of numerous black spines at the pronotal surface and by the shape of metanotal sclerites. Melampophylax austriacus, an endemic of the Eastern Alps, has spoon-shaped scraper mandibles lacking teeth. This character is shared with M. mucoreus (Hagen) and M. nepos (McLachlan), whereas in M. melampus (McLachlan) teeth are present at the mandibles as it is common for omnivorous shredders. Such intra-generic functional diversity questions trait classifications on higher taxonomic units like genus or family. 相似文献