Physics and Chemistry of the Earth, Part B: Hydrology, Oceans and Atmosphere最新文献_第5页

Transition mechanism of debris flows over rigid bed to over erodible bed 泥石流从刚性床层向可蚀性床层的过渡机理

Physics and Chemistry of the Earth, Part B: Hydrology, Oceans and Atmosphere Pub Date : 2001-01-01 DOI: 10.1016/S1464-1909(00)00235-5

S Egashira , T Itoh , H Takeuchi

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引用次数: 44

The importance of sediment characteristics and trap efficiency in assessing sediment yield using retention ponds 泥沙特征和捕集器效率在利用截留池评估产沙量中的重要性

Physics and Chemistry of the Earth, Part B: Hydrology, Oceans and Atmosphere Pub Date : 2001-01-01 DOI: 10.1016/S1464-1909(01)85019-X

G. Verstraeten, J. Poesen

引用次数: 16

Reconstruction of daily global radiation for past years for use in agricultural models 用于农业模式的历年全球日辐射重建

Physics and Chemistry of the Earth, Part B: Hydrology, Oceans and Atmosphere Pub Date : 2001-01-01 DOI: 10.1016/S1464-1909(00)00248-3

H. Oesterle

{"title":"Reconstruction of daily global radiation for past years for use in agricultural models","authors":"H. Oesterle","doi":"10.1016/S1464-1909(00)00248-3","DOIUrl":"10.1016/S1464-1909(00)00248-3","url":null,"abstract":"<div><p>A method of estimation of daily global radiation based on standard meteorological observations is presented. Global radiation may be calculated with one-dimensional regression equations, either with or without conditions (constraints). Daily duration of sunshine, mean cloudiness or temperature range can be used as predictors in either case. In general to select the proper equations with conditions, humidity was chosen as a master variable. Formulation and validation of the regression equations is done on the basis of data from 42 German radiation stations. The annual root mean square error (RMSE) between values calculated for individual days with the estimation method developed, and measured data, was about 1.6 MJ m<sup>−2</sup> day<sup>−1</sup> using sunshine duration as the predictor and 3.0 MJ m<sup>−2</sup> day<sup>−1</sup> using both temperature range and relative humidity as predictors.</p><p>This estimation method has been used for reconstruction of daily global radiation for about 400 German meteorological stations for years, and for stations without observations of global radiation. Reconstructed data will be used in agricultural and hydrological models.</p></div>","PeriodicalId":101025,"journal":{"name":"Physics and Chemistry of the Earth, Part B: Hydrology, Oceans and Atmosphere","volume":"26 3","pages":"Pages 253-256"},"PeriodicalIF":0.0,"publicationDate":"2001-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S1464-1909(00)00248-3","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73202322","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: 31

A Cellular Automata model for soil erosion by water 水对土壤侵蚀的元胞自动机模型

Physics and Chemistry of the Earth, Part B: Hydrology, Oceans and Atmosphere Pub Date : 2001-01-01 DOI: 10.1016/S1464-1909(01)85011-5

D. D'Ambrosio , S. Di Gregorio , S. Gabriele , R. Gaudio

引用次数: 121

Study of time dependency of factors affecting the spatial distribution of soil water content in a field-plot 农田土壤含水量空间分布影响因子的时间依赖性研究

Physics and Chemistry of the Earth, Part B: Hydrology, Oceans and Atmosphere Pub Date : 2001-01-01 DOI: 10.1016/S1464-1909(01)00060-0

D. Jacques , B. Mohanty , A. Timmerman , J. Feyen

{"title":"Study of time dependency of factors affecting the spatial distribution of soil water content in a field-plot","authors":"D. Jacques , B. Mohanty , A. Timmerman , J. Feyen","doi":"10.1016/S1464-1909(01)00060-0","DOIUrl":"10.1016/S1464-1909(01)00060-0","url":null,"abstract":"<div><p>Temporal and spatial variability of water content in soil results from a complex interaction of different factors such as duration and frequency of rainfall, soil layering, vegetation, and topography. The objectives of this study were (i) to use a resistant median-polishing scheme to quantify the temporal variability of a depth and a horizontal location factor in an additive model, and (ii) to investigate the time stability of those two factors at a detailed temporal scale during different infiltration and redistributions cycles. Time series of water content were measured at 5 depths and 12 locations along a transect of 6 m using Time Domain Reflectometry (TDR). Measurements were repeated every 2-hours for 168 days under natural boundary conditions. At each time step, the mean water content of the soil profile, 5 depth factors and 12 location factors were estimated. The time series of these factors were qualitatively interpreted and related to the atmospheric and prevailing soil conditions. It was found that micro-heterogeneity plays an important role, even at this small plot-scale. The relative contributions of the factors were dependent on the antecedent soil moisture conditions. Also, the ratio of the deterministic variance, i.e., variance explained by the deterministic factors, of water content to the observed variance is variable in time.</p></div>","PeriodicalId":101025,"journal":{"name":"Physics and Chemistry of the Earth, Part B: Hydrology, Oceans and Atmosphere","volume":"26 7","pages":"Pages 629-634"},"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)00060-0","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73748326","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: 23

Correction of synoptic precipitation observations due to systematic measuring errors with special regard to precipitation phases 由于系统测量误差引起的天气性降水观测的校正，特别是关于降水阶段的校正

Physics and Chemistry of the Earth, Part B: Hydrology, Oceans and Atmosphere Pub Date : 2001-01-01 DOI: 10.1016/S1464-1909(01)00070-3

T. Fuchs , J. Rapp , F. Rubel , B. Rudolf

引用次数: 74

Fluid exchange between a recirculation region and the perturbed external flow 再循环区域与受扰动的外部流之间的流体交换

Physics and Chemistry of the Earth, Part B: Hydrology, Oceans and Atmosphere Pub Date : 2001-01-01 DOI: 10.1016/S1464-1909(01)00005-3

C. Piccolo, R. Arina, C. Cancelli

引用次数: 1

Ground-based remote sensing of atmospheric parameters using integrated profiling stations 基于综合剖面站的地面大气参数遥感

Physics and Chemistry of the Earth, Part B: Hydrology, Oceans and Atmosphere Pub Date : 2001-01-01 DOI: 10.1016/S1464-1909(00)00243-4

D.A.M. Engelbart, H. Steinhagen

引用次数: 6

PODIUM: Projecting water supply and demand for food production in 2025 讲台:预测2025年粮食生产用水供应和需求

Physics and Chemistry of the Earth, Part B: Hydrology, Oceans and Atmosphere Pub Date : 2001-01-01 DOI: 10.1016/S1464-1909(01)00099-5

C. de Fraiture, D. Molden, U. Amarasinghe, I. Makin

{"title":"PODIUM: Projecting water supply and demand for food production in 2025","authors":"C. de Fraiture, D. Molden, U. Amarasinghe, I. Makin","doi":"10.1016/S1464-1909(01)00099-5","DOIUrl":"10.1016/S1464-1909(01)00099-5","url":null,"abstract":"<div><p>Since 1997, IWMI has been developing models to investigate future food and water requirements. Since the initial results were published (Seckler et al., 1998), the data and methodologies were refined substantially, evolving into the PODIUM model. The model estimates projected increases in water demand in 2025 resulting from the expected population growth and changes in consumption pattern, for individual nations. The PODIUM model provides a user-friendly means to analyze alternative future scenarios and conduct sensitivity analysis.</p><p>As part of the World Water Vision 2025 exercise, the PODIUM model was used to test a range of scenarios related to food and water demand. In the IWMI base scenario, 33 percent of the population of the studied countries will face <em>absolute water scarcity</em>. These countries will not have sufficient water resources to meet water needs.</p><p>Another 45 percent of the population live in countries that will face <em>economic scarcity</em>. Countries in this category may not have the capacity or financial resources to develop sufficient water resources. Globally, water diversions to agriculture will grow by 17 percent. Fifteen countries, mainly in the Middle East and Africa, will rely on cereal imports for more than 25 percent of their grain consumption (Seckler et al., 2000).</p><p>This paper presents the modeling strategies adopted in the PODIUM model and the results obtained during the development of the World Water Vision (Rijsberman and Cosgrove, 2000). These results indicate the need for substantial investment in water resources development, improving agricultural water use and expansion of both irrigated and rain-fed agriculture.</p></div>","PeriodicalId":101025,"journal":{"name":"Physics and Chemistry of the Earth, Part B: Hydrology, Oceans and Atmosphere","volume":"26 11","pages":"Pages 869-876"},"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)00099-5","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85854962","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: 36

Density-dependent groundwater movement in sediments overlying salt domes - the Gorleben site example 盐丘上沉积物中依赖密度的地下水运动——戈莱本遗址的例子

Physics and Chemistry of the Earth, Part B: Hydrology, Oceans and Atmosphere Pub Date : 2001-01-01 DOI: 10.1016/S1464-1909(01)00019-3

K. Schelkes, P. Vogel, H. Klinge

引用次数: 4