Physics and Chemistry of the Earth, Part A: Solid Earth and Geodesy最新文献

{"title":"Thematic volume on “compaction, subsidence and the mechanics of granular materials”","authors":"C. David (Guest editor of Physics and Chemistry of the Earth), N. Petford (Guest editor of Physics and Chemistry of the Earth), R. Risnes (Guest editor of Physics and Chemistry of the Earth)","doi":"10.1016/S1464-1895(01)80003-X","DOIUrl":"10.1016/S1464-1895(01)80003-X","url":null,"abstract":"","PeriodicalId":101024,"journal":{"name":"Physics and Chemistry of the Earth, Part A: Solid Earth and Geodesy","volume":"26 1","pages":"Pages 1-2"},"PeriodicalIF":0.0,"publicationDate":"2001-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S1464-1895(01)80003-X","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88713097","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The role of water vapour in the atmosphere. A short overview from a climate modeller's point of view","authors":"D. Jacob","doi":"10.1016/S1464-1895(01)00094-1","DOIUrl":"10.1016/S1464-1895(01)00094-1","url":null,"abstract":"<div><p>Water vapour plays a dominant role in the radiative balance and the hydrological cycle. It is a principal element in the thermodynamics of the atmosphere, it transports latent heat, it contributes to absorption and emission in a n umber of bands and it condenses into clouds that reflect and adsorb solar radiation, thus directly affecting the energy balance. In the lower atmosphere, the water vapour concentrations can vary by orders of magnitude from place to place. This variability creates a fundamental problem in climate modelling due to the very high temporal and spatial resolution needed to resolve all processes creating the sharp gradients which are related to the variability. The contribution of water vapour to atmospheric phenomena on different time and space scales for today's and future climates are discussed as well as the importance of water vapour monitoring. The latter is a prerequisite for model validation and an important contribution to the understanding of the behaviour of the atmosphere. It is shown that only the validation of more than one component of the hydrological cycle leads to a better understanding and an improvement of the simulations.</p></div>","PeriodicalId":101024,"journal":{"name":"Physics and Chemistry of the Earth, Part A: Solid Earth and Geodesy","volume":"26 6","pages":"Pages 523-527"},"PeriodicalIF":0.0,"publicationDate":"2001-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S1464-1895(01)00094-1","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79607586","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Nd and Sr isotopic compositions of igneous rocks from the Lower Yangtze region in eastern China: constraints on sources","authors":"J.-F. Chen ,&nbsp;J. Yan ,&nbsp;Z. Xie ,&nbsp;X. Xu ,&nbsp;F. Xing","doi":"10.1016/S1464-1895(01)00122-3","DOIUrl":"10.1016/S1464-1895(01)00122-3","url":null,"abstract":"<div><p>Nd and Sr isotopic data are compiled from literatures for Mesozoic igneous rocks in the Lower Yangtze region, eastern China. These Mesozoic igneous rocks have been classified into three associations: Na-enriched (alkaline mafic) association, K-enriched association which includes shoshonitic series and ultrapotassic rocks, and high potassium calc-alkaline (HKCA) association. The HKCA association has been further divided into three geographical sub-groups: the rocks north to, along and south to the Yangtze River.</p><p>The Na-enriched mafic rocks show ε_Nd(T) of 1.4 to −9.9 and ⁸⁷Sr/⁸⁶Sr(T) of 0.7047 to 0.7077. The K-enriched rock association shows ε_Nd(T) of −1.8 to −9.3 and ⁸⁷Sr/⁸⁷Sr(T) of 0.7053 to 0.7092. Low SiO₂ in the rocks suggests that they are mantle-derived. These Nd-Sr isotopic variations may represent isotopic feature in the mantle source of these rocks. The Mesozoic mantle of this region is thus enriched to slightly depleted and highly heterogeneous in terms of Sr and Nd isotopic characteristics. The isotopic characters of the Mesozoic mantle of the region can be modeled by mixing between DMM component representing asthenospheric mantle and EM II representing lithospheric mantle. These characters closely resemble those of mafic and ultramafic rocks in the North Dabie terrane north to the region studied. This suggests that processes operating during continental collision and deep subduction in the Dabie orogenic belt might also operate in petrogenesis of mantle-derived rocks of the Lower Yangtze region. However, since the range of initial Sr and Nd isotopic ratios for the mantle-derived rocks in the Lower Yangtze region overlaps that of Mesozoic basalts from the eastern coast of China, it is yet not known if this is a prevalent phenomenon in the Mesozoic basalts from eastern China.</p><p>The intermediate and acid rocks of the HKCA association were most likely derived from mixing between the mantle-derived mafic magma and different crustal sources. The HKCA rocks occurring in the area north to the Yangtze River have ε_Nd(T) of −13.5 to −15.5 and ⁸⁷Sr/⁸⁶Sr(T) of 0.7058 to 0.7067. The low ε_Nd(T) and ⁸⁷Sr/⁸⁶Sr(T) suggest that a crustal source of old and depleted in Rb, such as the source of the Mesozoic granites from the Dabie terrain, was involved in the formation of this sub-group of rocks. The HKCA rocks along the Yangtze River show ε_Nd(T) of −7.0 to −16.5 and ⁸⁷Sr/⁸⁶Sr(T) of 0.7061 to 0.7101. Old crustal source, such as Archaean Kongling group and Paleoproterozoic Dongling group rocks, was involved in the formation of these rocks. The granitic rocks of the HKCA association in the area south to the Yangtze River show relatively constant ε_Nd(T) of −4.9 to −6.8 but variable ⁸⁷Sr/⁸⁶Sr(T) of 0.7081 to 0.7104. The ε_Nd(T)","PeriodicalId":101024,"journal":{"name":"Physics and Chemistry of the Earth, Part A: Solid Earth and Geodesy","volume":"26 9","pages":"Pages 719-731"},"PeriodicalIF":0.0,"publicationDate":"2001-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S1464-1895(01)00122-3","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86237966","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"GPS zenith tropospheric delay (ZTD) variability in the Mediterranean","authors":"J.S. Haase ,&nbsp;H. Vedel ,&nbsp;M. Ge ,&nbsp;E. Calais","doi":"10.1016/S1464-1895(01)00080-1","DOIUrl":"10.1016/S1464-1895(01)00080-1","url":null,"abstract":"<div><p>In the context of the MAGIC project (Meteorological Applications of GPS Integrated Column Water Vapor Measurements in the Western Mediterranean), zenith tropospheric delays (ZTD) are computed from Global Positioning System (GPS) signals at permanent sites in the western Mediterranean area continuously since November 1998. These time series are compared to the equivalent values estimated by integrating the atmospheric column derived from radiosonde profiles and the HIRLAM numerical weather prediction model in order to determine the error statistics of the data. From a year and a half of data, we show that the difference between radiosonde and GPS ZTD has a standard deviation of 12 mm and a bias of less than 5 mm for most stations. The biases between the GPS ZTD and HIRLAM estimates are smaller, but the standard deviation is greater, usually on the order of 17 mm. The standard deviation of the residuals from both comparisons depends greatly on the humidity which produces an annual signal because of the much higher humidity variability in the summer months.</p></div>","PeriodicalId":101024,"journal":{"name":"Physics and Chemistry of the Earth, Part A: Solid Earth and Geodesy","volume":"26 6","pages":"Pages 439-443"},"PeriodicalIF":0.0,"publicationDate":"2001-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S1464-1895(01)00080-1","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77363511","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"On hourly orbit determination","authors":"J. Douša,&nbsp;L. Mervart","doi":"10.1016/S1464-1895(01)00100-4","DOIUrl":"10.1016/S1464-1895(01)00100-4","url":null,"abstract":"<div><p>We present here our hourly orbit product and we compare it to other near real-time (NRT) reliable orbits. The comparisons are based on satellite position differences with respect to the final IGS orbits. Experience shows that the use of predicted precise orbits in the NRT processing mode is usually problematic due to poorly determined arcs of only a few satellites. Thus, evaluation of satellite orbits is necessary. Nevertheless, we can find a decreased quality of some arcs also in ultra-rapid products, but the magnitude is significantly lower here. Reducing the predictions to 1–2 hours only, our hourly orbits improve especially the along-track satellite positions.</p></div>","PeriodicalId":101024,"journal":{"name":"Physics and Chemistry of the Earth, Part A: Solid Earth and Geodesy","volume":"26 6","pages":"Pages 555-560"},"PeriodicalIF":0.0,"publicationDate":"2001-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S1464-1895(01)00100-4","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89395494","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparison of software and techniques for water vapor estimation using German near real-time GPS data","authors":"G. Gendt ,&nbsp;G. Dick ,&nbsp;A. Rius ,&nbsp;P. Sedo","doi":"10.1016/S1464-1895(01)00076-X","DOIUrl":"10.1016/S1464-1895(01)00076-X","url":null,"abstract":"<div><p>To deliver tropospheric water vapor contents derived from GPS ground networks for the assimilation into numerical weather prediction models the GPS data have to be analyzed within near real-time with a delay of about one hour. Two near real-time processors for the trophospheric water vapor monitoring developed at IEEC Barcelona and GFZ Potsdam are compared using one week of data acquired in the German near real-time network. The resulting small differences in the integrated water vapor being on the level of 1–2 mm precipitable water vapor reflect that both processors fulfill the requirements for numerical weather predictions. Therefore the standardization for processors should not be too strict not to obstruct a fruitful competition in the software developments and improvements.</p></div>","PeriodicalId":101024,"journal":{"name":"Physics and Chemistry of the Earth, Part A: Solid Earth and Geodesy","volume":"26 6","pages":"Pages 417-420"},"PeriodicalIF":0.0,"publicationDate":"2001-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S1464-1895(01)00076-X","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86310502","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Atmospheric water vapour content determined from zenith delay assuming a local model of troposphere","authors":"K. Kuyrzyńska,&nbsp;A. Gabryszewska","doi":"10.1016/S1464-1895(01)00040-0","DOIUrl":"10.1016/S1464-1895(01)00040-0","url":null,"abstract":"<div><p>The local model of troposphere is constructed on the basis of 7300 individual aerological soundings performed and processed over a period of 10 years in Poznań, Poland. The values of the zenith wet delay (ZWD) calculated using this model are shown to coincide very well with the real values obtained directly from individual aerological soundings, the systematic differences between them are not greater than the error of ZWD determination. Much larger differences were obtained assuming the standard model commonly used and the values estimated from the GPS measurements. The differences are particularly large in summer. The local model of troposphere is concluded to be the optimum for determination of water vapour content from ZWD.</p></div>","PeriodicalId":101024,"journal":{"name":"Physics and Chemistry of the Earth, Part A: Solid Earth and Geodesy","volume":"26 3","pages":"Pages 159-163"},"PeriodicalIF":0.0,"publicationDate":"2001-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S1464-1895(01)00040-0","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82491384","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The IGS global data center at the CDDIS - an update","authors":"C. Noll ,&nbsp;M. Dube","doi":"10.1016/S1464-1895(01)00108-9","DOIUrl":"10.1016/S1464-1895(01)00108-9","url":null,"abstract":"<div><p>The Crustal Dynamics Data Information System (CDDIS) has served as a global data center for the International GPS Service (IGS) since its start in June 1992, providing on-line access to data from over 175 sites on a daily basis. This paper will present information about the GPS and GLONASS data and products archive at the CDDIS. General information about the system and its support of other international space geodesy services (the ILRS, IVS, IGLOS-PP, and DPE) will also be discussed.</p></div>","PeriodicalId":101024,"journal":{"name":"Physics and Chemistry of the Earth, Part A: Solid Earth and Geodesy","volume":"26 6","pages":"Pages 603-604"},"PeriodicalIF":0.0,"publicationDate":"2001-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S1464-1895(01)00108-9","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80666068","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"GPS ground station data for CHAMP radio occultation measurements","authors":"J. Wickert,&nbsp;R. Galas,&nbsp;G. Beyerle,&nbsp;R. König,&nbsp;C. Reigber","doi":"10.1016/S1464-1895(01)00092-8","DOIUrl":"10.1016/S1464-1895(01)00092-8","url":null,"abstract":"<div><p>The role of GPS ground station data for the CHAMP Atmospheric Profiling experiment is discussed. The profiling activities at GeoForschungZentrum Potsdam (GFZ) are briefly described and first results of the occultation processing system are presented. The atmospheric excess phase of the occultation link between the CHAMP and the GPS satellite is derived by a double difference method using ground station data. The influence of ground station data on the accuracy of the derived atmospheric profiles is discussed. A relationship between the temperature errors at several heights resulting from errors in atmospheric excess phase is given, e.g. an error of 1mm/s in the time derivative of the excess phase results in a temperature error of 1 K at 30 km. Furthermore, a study was performed to estimate the required data rate of the ground station measurements. In particular the influence of the Selective Availability (SA) termination on May 2, 2000 is emphasized. We conclude that the acquisition rate can be reduced from 1 Hz to 0.1 Hz without loss of information. Simulations of the CHAMP occultation experiment show that the joint Jet Propulsion Laboratory, Pasadena (JPL) &amp; GFZ “high rate &amp; low latency” network enables the processing of globally distributed occultation events with a highly redundant number of ground stations. Latency aspects are studied in view of the future task of providing atmospheric occultation data for operational weather forecast.</p></div>","PeriodicalId":101024,"journal":{"name":"Physics and Chemistry of the Earth, Part A: Solid Earth and Geodesy","volume":"26 6","pages":"Pages 503-511"},"PeriodicalIF":0.0,"publicationDate":"2001-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S1464-1895(01)00092-8","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80996398","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An assessment of the quality of GPS/MET radio limb soundings during February 1997","authors":"C. Marquardt, K. Labitzke, C. Reigber, T. Schmidt, J. Wickert","doi":"10.1016/S1464-1895(01)00035-7","DOIUrl":"https://doi.org/10.1016/S1464-1895(01)00035-7","url":null,"abstract":"","PeriodicalId":101024,"journal":{"name":"Physics and Chemistry of the Earth, Part A: Solid Earth and Geodesy","volume":"1 1","pages":"125-130"},"PeriodicalIF":0.0,"publicationDate":"2001-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90227963","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}