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Rudolf BráZdil Christian Pfister Heinz Wanner Hans Von Storch JüRg Luterbacher 《Climatic change》2001,48(4):653-655
Volume Contents
Contents of Volume 48 相似文献233.
A. Skopal M. Vako T. Pribulla D. Chochol E. Semkov M. Wolf A. Jones 《Astronomische Nachrichten》2007,328(9):909-916
We present new photometric observations of 15 symbiotic stars covering their last orbital cycle(s) from 2003.9 to 2007.2. We obtained our data by both classical photoelectric and CCD photometry. Main results are: EG And brightened by ∼0.3 mag in U from 2003. A ∼0.5 mag deep primary minimum developed in the U light curve (LC) at the end of 2006. ZAnd continues its recent activity that began during the 2000 autumn. A new small outburst started in summer of 2004 with a peak U magnitude of ∼ 9.2. During the spring of 2006 the star entered a massive outburst. It reached its historical maximum at U ∼ 8.0 in 2006 July. AEAra erupted in 2006 February with Δmvis ∼ 1.2 mag. BF Cyg entered a new active stage in 2006 August. A brightness maximum (U ∼ 9.4) was measured during 2006 September. CH Cyg persists in a quiescent phase. During 2006 June–December a ∼ 2 mag decline in all colours was measured. CI Cyg started a new active phase during 2006 May–June. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
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Deriving snow‐cover depletion curves for different spatial scales from remote sensing and snow telemetry data
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Steven R. Fassnacht Graham A. Sexstone Amir H. Kashipazha Juan Ignacio López‐Moreno Michael F. Jasinski Stephanie K. Kampf Benjamin C. Von Thaden 《水文研究》2016,30(11):1708-1717
During the melting of a snowpack, snow water equivalent (SWE) can be correlated to snow‐covered area (SCA) once snow‐free areas appear, which is when SCA begins to decrease below 100%. This amount of SWE is called the threshold SWE. Daily SWE data from snow telemetry stations were related to SCA derived from moderate‐resolution imaging spectroradiometer images to produce snow‐cover depletion curves. The snow depletion curves were created for an 80 000 km2 domain across southern Wyoming and northern Colorado encompassing 54 snow telemetry stations. Eight yearly snow depletion curves were compared, and it is shown that the slope of each is a function of the amount of snow received. Snow‐cover depletion curves were also derived for all the individual stations, for which the threshold SWE could be estimated from peak SWE and the topography around each station. A station's peak SWE was much more important than the main topographic variables that included location, elevation, slope, and modelled clear sky solar radiation. The threshold SWE mostly illustrated inter‐annual consistency. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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In 2005, a German research project was started to develop a novel approach to prove safety for a HLW repository in a salt formation, to refine the safety concept, to identify open scientific issues and to define necessary R&D work. This project aimed at identifying the key information for a HLW repository in salt. One important question is how this information may be best fulfilled by natural analogue studies. This question is answered by starting a review of the required key information needs of the safety case (post-closure phase) in order to assess whether or not these requirements can be supported by natural analogues information. In order to structure the review and to address the key elements of the safety concepts, three types of natural analogues are distinguished: (i) natural analogues for the integrity of the geological barrier, (ii) natural analogues for the integrity of the geotechnical barriers and (iii) natural analogues for release scenarios. For the safety case in salt type (i) and (ii) are of highest importance and are treated in this paper. The assessment documented in this paper on the one hand indicates the high potential benefit of natural analogues for a safety case in salt and on the other hand helps to focus the available human and financial resources for the safety case on the most safety-relevant aspects. 相似文献
237.
Marjorie Schulz David Stonestrom Guntram Von Kiparski Corey Lawrence Carrie Masiello Art White John Fitzpatrick 《Applied Geochemistry》2011
Concentrations of CO2 in soil atmosphere and CO2 efflux were measured across a marine terrace soil chronosequence near Santa Cruz, California. Soil development, specifically the formation of an argillic horizon, has created a two-tier soil gas profile in the older terrace soils. The soil above the argillic horizon has seasonal variations in soil CO2 associated with plant respiration. The older soils with dense argillic horizons maintain a year round ~1%CO2 below the argillic horizon. The CO2efflux during the growing season is higher on the older terraces. 相似文献
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Emil Wolf 《Astrophysics and Space Science》1995,227(1-2):277-297
This article is essentially the text of lectures presented September 7, 1982 at the Max Born Centenary Conference held in Edinburgh, Scotland and October 21, 1982 at the Max Born Symposium held during the Annual Meeting of the Optical Society of America.Emil Wolf is Wilson Professor of Optical Physics at the University of Rochester. Reprinted fromOptics News, November/December 1983 with permisssion from the author and the Optical Society of America 相似文献
240.