Physics and Chemistry of the Earth, Part B: Hydrology, Oceans and Atmosphere最新文献_第10页

Measuring change in sterol input to estuarine sediments 测量河口沉积物中固醇输入的变化

Physics and Chemistry of the Earth, Part B: Hydrology, Oceans and Atmosphere Pub Date : 2001-01-01 DOI: 10.1016/S1464-1909(01)00081-8

A.D. Reeves , D. Patton

{"title":"Measuring change in sterol input to estuarine sediments","authors":"A.D. Reeves , D. Patton","doi":"10.1016/S1464-1909(01)00081-8","DOIUrl":"https://doi.org/10.1016/S1464-1909(01)00081-8","url":null,"abstract":"<div><p>In complex estuarine environments suites of sterols can be used to define autochtonous and allochtonous sources of organic matter and to identify biological processes occurring <em>in situ</em>. Coprostanol is a major faecal sterol present in human waste (40%–60% of total faecal sterols excreted). As raw sewage is the primary source of this sterol, its determination is an effective measure of the degree of untreated sewage contamination. Mean concentrations of sterols in μg.g<sup>−1</sup> dry sediment are reported for the Tay Estuary. Ratios of coprostanol/cholesterol, coprostanol/epicoprostanol and the 5β/(5β + 5α) stanol index were used to assess and cross-validate sterol sources. These results have a special significance in that the disposal of raw sewage is being phased-out in north-east Scotland. Our study will therefore act as a record, showing the degree of contamination during discharge of raw sewage. Adherence to the EC Urban Waste Water Directive 1991 (91/271/EEC) by the Scottish Environmental Protection Agency and the North of Scotland Water Authority, means that all sewage sludge should receive primary treatment. This work establishes a baseline against which reduction in sedimentary sterol concentrations can be measured.</p></div>","PeriodicalId":101025,"journal":{"name":"Physics and Chemistry of the Earth, Part B: Hydrology, Oceans and Atmosphere","volume":"26 9","pages":"Pages 753-757"},"PeriodicalIF":0.0,"publicationDate":"2001-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S1464-1909(01)00081-8","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"137441670","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}

引用次数: 0

The importance of water storage variations for water balance studies of the Baltic Sea 水储存变化对波罗的海水平衡研究的重要性

Physics and Chemistry of the Earth, Part B: Hydrology, Oceans and Atmosphere Pub Date : 2001-01-01 DOI: 10.1016/S1464-1909(01)00023-5

A. Lehmann, H.-H. Hinrichsen

{"title":"The importance of water storage variations for water balance studies of the Baltic Sea","authors":"A. Lehmann, H.-H. Hinrichsen","doi":"10.1016/S1464-1909(01)00023-5","DOIUrl":"10.1016/S1464-1909(01)00023-5","url":null,"abstract":"<div><p>The closing of the water and energy cycle of the Baltic Sea is one of the main aims of BALTEX (Baltic Sea Experiment), which particularily focuses on the exploration, modelling and quantification of the various processes determining the space and time variability of the energy and water budget. On the long-term mean the water budget of the Baltic Sea is determined by river runoff, net precipitation (precipitation minus evaporation) and the in- and outflows through the Baltic Sea entrance area, assuming that the mean sea level remains constant, i.e. the ability of the Baltic Sea to store a huge amount of water is averaged out over the long-term period. For shorter periods, the water storage which can be expressed by the mean sea level plays an important role on the water budget. The objective of the present study is to investigate the variability of the water storage of the Baltic Sea and relate its fluctuations to the different components of the water balance equation. The anomaly of the mean sea level of the Baltic Sea shows a well pronounced seasonal cycle, with negative values between the end of February to the end of June (minimum in the middle of May), and positive anomalies from July to mid-February (maximum in January). There is a high correlation between the mean sea level expressed by the Landsort tide gauge and the local atmospheric conditions over the Baltic Sea. The annual course of the total water balance is controlled by the local atmospheric conditions with the net fresh-water inflow only controls the general outflow conditions. Sea level, precipitation and river runoff have been obtained from observations provided by the SMHI. For the in- and outflow through the entrance area of the Baltic Sea and evaporation over the open ocean, coupled sea ice-ocean model simulations for a 10-years period have been utilized.</p></div>","PeriodicalId":101025,"journal":{"name":"Physics and Chemistry of the Earth, Part B: Hydrology, Oceans and Atmosphere","volume":"26 5","pages":"Pages 383-389"},"PeriodicalIF":0.0,"publicationDate":"2001-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S1464-1909(01)00023-5","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73136263","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}

引用次数: 11

Reconstructing historic reservoir sedimentation rates using data-based mechanistic modelling 利用基于数据的机制模型重建历史水库沉积速率

Physics and Chemistry of the Earth, Part B: Hydrology, Oceans and Atmosphere Pub Date : 2001-01-01 DOI: 10.1016/S1464-1909(01)85018-8

J.S. Rowan , L.E. Price , C.P. Fawcett , P.C. Young

引用次数: 13

Adaptivity in the finite volume discretization of variable density flows in porous media 多孔介质中变密度流动有限体积离散化的适应性

Physics and Chemistry of the Earth, Part B: Hydrology, Oceans and Atmosphere Pub Date : 2001-01-01 DOI: 10.1016/S1464-1909(01)00013-2

P. Knabner, Ch. Tapp, K. Thiele

引用次数: 3

Modelling variable density groundwater flow 模拟变密度地下水流动

Physics and Chemistry of the Earth, Part B: Hydrology, Oceans and Atmosphere Pub Date : 2001-01-01 DOI: 10.1016/S1464-1909(01)00015-6

C.P. Jackson, S.P. Watson

引用次数: 2

Fuzzy rule-based prediction of monthly precipitation 基于模糊规则的月降水量预测

Physics and Chemistry of the Earth, Part B: Hydrology, Oceans and Atmosphere Pub Date : 2001-01-01 DOI: 10.1016/S1464-1909(01)00066-1

R. Pongracz , J. Bartholy , I. Bogardi

{"title":"Fuzzy rule-based prediction of monthly precipitation","authors":"R. Pongracz , J. Bartholy , I. Bogardi","doi":"10.1016/S1464-1909(01)00066-1","DOIUrl":"10.1016/S1464-1909(01)00066-1","url":null,"abstract":"<div><p>Monthly precipitation in Hungary is modeled using the Hess-Brezowsky atmospheric circulation pattern types and an ENSO index as forcing functions or inputs. The weakness of the statistical dependence between these individual inputs and precipitation prevents the use of a multivariate regression analysis for reproducing the probability distribution function of observed precipitation. In order to utilize the existing relationship between forcing functions and precipitation a fuzzy rule-based modeling technique is used. The first part of the observed input and precipitation data is used as the learning set to identify the fuzzy rules. Then, the second part of the data is used to validate the rules by comparing the frequency distributions of precipitation calculated respectively with the fuzzy rules and observed data. Example results are presented for two different climatic regions of Hungary. One of them represents a wetter climate while the other refers to the drier conditions of the Hungarian Plains. The fuzzy rule-based model reproduces the empirical frequency distributions in every season. However, as expected, the statistical prediction is better in winter, spring and fall than in the summer. The potential of the approach is important in climate change studies when the fuzzy rules obtained as described above can be used with input data stemming from GCM to predict regional/local precipitation reflecting GCM scenarios.</p></div>","PeriodicalId":101025,"journal":{"name":"Physics and Chemistry of the Earth, Part B: Hydrology, Oceans and Atmosphere","volume":"26 9","pages":"Pages 663-667"},"PeriodicalIF":0.0,"publicationDate":"2001-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S1464-1909(01)00066-1","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80775286","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}

引用次数: 29

Parameterisation of radionuclide deposition in atmospheric long-range transport modelling 大气远程输运模拟中放射性核素沉积的参数化

Physics and Chemistry of the Earth, Part B: Hydrology, Oceans and Atmosphere Pub Date : 2001-01-01 DOI: 10.1016/S1464-1909(01)00087-9

A. Baklanov, J.H. Sørensen

{"title":"Parameterisation of radionuclide deposition in atmospheric long-range transport modelling","authors":"A. Baklanov, J.H. Sørensen","doi":"10.1016/S1464-1909(01)00087-9","DOIUrl":"10.1016/S1464-1909(01)00087-9","url":null,"abstract":"<div><p>Radionuclides are released into the atmosphere in the form of gases or aerosols. The aerosols have different particle sizes (0.01–60 μm). This paper analyses parameterisations of the removal processes by dry and wet deposition of radionuclides to the ground, and recommends some parameterisations and their realisation for the DERMA model as an example. It is shown that the washout coefficient strongly depends on the particle size. This dependence, however, is not included in most atmospheric dispersion models. Therefore, a revised formulation of the wet deposition parameterisation for particles of different size is suggested. The effect of gravitational settling is included in the dry deposition parameterisation by a combination of Stokes' law with the Cunningham correction for small particles and an iterative procedure solving the differential equation for the terminal settling velocity for large particles. Comparisons of simulation results for the Algeciras accident, Spain, with measurement data from the European monitoring network are presented and discussed.</p></div>","PeriodicalId":101025,"journal":{"name":"Physics and Chemistry of the Earth, Part B: Hydrology, Oceans and Atmosphere","volume":"26 10","pages":"Pages 787-799"},"PeriodicalIF":0.0,"publicationDate":"2001-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S1464-1909(01)00087-9","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80019599","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}

引用次数: 191

Two-years of boundary layer measurements with a sodar - statistics and applications 两年的边界层测量用雷达-统计及应用

Physics and Chemistry of the Earth, Part B: Hydrology, Oceans and Atmosphere Pub Date : 2001-01-01 DOI: 10.1016/S1464-1909(00)00241-0

K. Baumann, M. Piringer

引用次数: 6

Diapycnal mixing in a frontal system forced by an oscillating deformation field 在振荡变形场的强迫下，锋面系统中的横向混合

Physics and Chemistry of the Earth, Part B: Hydrology, Oceans and Atmosphere Pub Date : 2001-01-01 DOI: 10.1016/S1464-1909(01)00009-0

A. Rodríguez-Santana, J.L. Pelegrí, P. Sangra

{"title":"Diapycnal mixing in a frontal system forced by an oscillating deformation field","authors":"A. Rodríguez-Santana, J.L. Pelegrí, P. Sangra","doi":"10.1016/S1464-1909(01)00009-0","DOIUrl":"10.1016/S1464-1909(01)00009-0","url":null,"abstract":"<div><p>A frontogenesis model with shear-induced diapycnal mixing has been developed to investigate the importance of mixing in the evolution of a frontal system. The model estimates the intensity of mixing induced by geostrophic shear through the mean density tendency, which represents the material derivative of the mean density due to the divergence of the vertical density flux. This flux is determined by the vertical gradient of the mean density and the turbulent diffusivity, the latter being related to the gradient Richardson number. The process of frontogenesis is based on an oscillating horizontal deformation field characterised by a compression phase and an expansion phase. During the compression phase both the vertical density gradient and the diapycnal velocity gradient increase their values. Therefore the gradient Richardson number decreases and the density tendency increases, characterising zones with high diapycnal mass convergence/divergence. These high values cause significant mixing and a redistribution of the isopycnal surfaces that persist in the phase of expansion. In this last phase, the gradient Richardson number increases leading to a decay of the diapycnal mixing, except in zones where mixing maintains its intensity.</p></div>","PeriodicalId":101025,"journal":{"name":"Physics and Chemistry of the Earth, Part B: Hydrology, Oceans and Atmosphere","volume":"26 4","pages":"Pages 293-298"},"PeriodicalIF":0.0,"publicationDate":"2001-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S1464-1909(01)00009-0","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85698401","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}

引用次数: 3

A PV-streamer's role in a succession of heavy rain-producing MCSs over the Central United States 在美国中部上空一连串强降雨的mcs中，一个视频流的作用

Physics and Chemistry of the Earth, Part B: Hydrology, Oceans and Atmosphere Pub Date : 2001-01-01 DOI: 10.1016/S1464-1909(01)00063-6

F. Caracena , A. Marroquin , E. Tollerud

引用次数: 3