Physics and Chemistry of the Earth, Part C: Solar, Terrestrial & Planetary Science最新文献_第2页

A method for processing ionograms based on correlation technique 一种基于相关技术的离子图处理方法

Physics and Chemistry of the Earth, Part C: Solar, Terrestrial & Planetary Science Pub Date : 2001-01-01 Epub Date: 2001-06-04 DOI: 10.1016/S1464-1917(01)00015-0

C. Scotto

引用次数: 4

Rainfall intermittency and the sampling error of tipping-bucket rain gauges 降雨的间歇性与翻斗式雨量计的抽样误差

Physics and Chemistry of the Earth, Part C: Solar, Terrestrial & Planetary Science Pub Date : 2001-01-01 Epub Date: 2002-02-14 DOI: 10.1016/S1464-1917(01)95018-4

A. Molini, P. La Barbera, L.G. Lanza, L. Stagi

{"title":"Rainfall intermittency and the sampling error of tipping-bucket rain gauges","authors":"A. Molini, P. La Barbera, L.G. Lanza, L. Stagi","doi":"10.1016/S1464-1917(01)95018-4","DOIUrl":"10.1016/S1464-1917(01)95018-4","url":null,"abstract":"<div>This work amplifies upon the influence of rainfall intermittency on pluviometric time series. Intermittency is here defined as the percentage of no-rain periods within a rainfall event, and can be interpreted as a sort of ‘stochastic intermittency’. When measuring an intermittent or, in general, ‘erratic’ signal, a relevant source of error is associated with the sampling procedure. By using numerical simulation of intermittent rainfall events, we focus on the deriving pattern of sampling errors within rainfall measurements obtained from any classic tipping-bucket rain gauge. The analysis, performed in both the time and frequency domain, reveals a strong inverse linear dependence between rainfall intermittency and the sampling errors, while a weak dependence on the autocorrelation of synthetic rainfall events is shown. The average absolute error is around 30% for the events analysed while the error at each sampling period peaks values higher than 100%. A direct influence of intermittency on the statistical characteristics of measured rainfall events is observed.</div>","PeriodicalId":101026,"journal":{"name":"Physics and Chemistry of the Earth, Part C: Solar, Terrestrial & Planetary Science","volume":"26 10","pages":"Pages 737-742"},"PeriodicalIF":0.0,"publicationDate":"2001-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S1464-1917(01)95018-4","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89451300","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: 50

Experimental study on the entrainment of bed material into debris flow 泥石流中床质夹带的实验研究

Physics and Chemistry of the Earth, Part C: Solar, Terrestrial & Planetary Science Pub Date : 2001-01-01 Epub Date: 2001-09-17 DOI: 10.1016/S1464-1917(01)00062-9

S. Egashira , N. Honda , T. Itoh

{"title":"Experimental study on the entrainment of bed material into debris flow","authors":"S. Egashira , N. Honda , T. Itoh","doi":"10.1016/S1464-1917(01)00062-9","DOIUrl":"10.1016/S1464-1917(01)00062-9","url":null,"abstract":"<div>The present study describes entraining characteristics of bed material into debris flow, based on flume tests, numerical and dimensional analyses. Flume tests are conducted to investigate influences of bed sediment size on erosion rate by supplying debris flows having unsaturated sediment concentration onto erodible beds. Experimental results show that the relative erosion rate, E/E0, decreases monotonically with increase of relative sediment size, d/d0, although E/E0 changes slightly with sediment concentration of debris flow. Herein, E is the erosion rate of bed sediment of size, d, E0 is the erosion rate when solid particle size, d0, of debris flow, are the same of the erodible bed material. According to the relation between E/E0 and d/d0, erosion rate, E, can be estimated by using Egashira's formula for E0. Therefore, the validity of erosion rate formula for E0 is tested by solving numerically for debris flow characteristics in terms of governing equations. In addition, critical size of bed sediment entrainment is discussed by introducing non-dimensional effective bed shear stress which is formulated by using fluid shear stress (total shear stress minus yield stress), bed sediment size, d, specific weight of sediment particle in water and acceleration due to gravity, and it is found that the critical non-dimensional effective shear stress takes a value similar to critical Shields parameter for bed load movement.</div>","PeriodicalId":101026,"journal":{"name":"Physics and Chemistry of the Earth, Part C: Solar, Terrestrial & Planetary Science","volume":"26 9","pages":"Pages 645-650"},"PeriodicalIF":0.0,"publicationDate":"2001-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S1464-1917(01)00062-9","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90728929","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: 149

The Mu radar study of nonlinear advective accelerations in the lower and middle atmosphere 中低层大气非线性平流加速度的Mu雷达研究

Physics and Chemistry of the Earth, Part C: Solar, Terrestrial & Planetary Science Pub Date : 2001-01-01 Epub Date: 2001-06-29 DOI: 10.1016/S1464-1917(01)00025-3

N.M. Gavrilov , S. Fukao , H. Hashiguchi

引用次数: 1

Photodissociation of nitric oxide in the middle and upper atmosphere 中高层大气中一氧化氮的光解作用

Physics and Chemistry of the Earth, Part C: Solar, Terrestrial & Planetary Science Pub Date : 2001-01-01 Epub Date: 2001-08-01 DOI: 10.1016/S1464-1917(01)00043-5

K. Minschwaner, V. Starke

引用次数: 1

Origin and development of vertical propagating oscillations with periods of planetary waves in the ionospheric F region 电离层F区行星波周期垂直传播振荡的起源和发展

Physics and Chemistry of the Earth, Part C: Solar, Terrestrial & Planetary Science Pub Date : 2001-01-01 Epub Date: 2001-06-29 DOI: 10.1016/S1464-1917(01)00019-8

D. Altadill , E.M. Apostolov , J.G. Solé , Ch. Jacobi

引用次数: 40

Effects of gravity and planetary waves on the lower ionosphere as obtained from radio wave absorption measurements 从无线电波吸收测量得到的重力波和行星波对电离层下层的影响

Physics and Chemistry of the Earth, Part C: Solar, Terrestrial & Planetary Science Pub Date : 2001-01-01 Epub Date: 2001-06-29 DOI: 10.1016/S1464-1917(01)00018-6

J. Laštovička

{"title":"Effects of gravity and planetary waves on the lower ionosphere as obtained from radio wave absorption measurements","authors":"J. Laštovička","doi":"10.1016/S1464-1917(01)00018-6","DOIUrl":"10.1016/S1464-1917(01)00018-6","url":null,"abstract":"<div>This paper is an overview of effects of gravity and planetary waves on the lower ionosphere as obtained from radio wave absorption measurements. To transform gravity waves from the neutral atmosphere into the ionized component is not easy. The uncertainty caused by problems with transfer of oscillations from neutral to ionized component makes the use of daytime absorption measurements for gravity wave investigations largely impossible and allows us to use only nighttime radio wave absorption. Some results of gravity wave activity studies in the lower ionosphere, based on 5.5 year long data set, are presented: (i) The gravity wave activity is almost insensitive to QBO. (ii) It decreases from the solar cycle maximum to the solar cycle minimum by ∼30%. (iii) The Mt. Pinatubo volcanic effect is well expressed for longer periods ( > 2 hours) but not detectable at short periods (< 1 hour). (iv) There is no detectable seasonal variation at high solar activity but there is a tendency to summer maximum at medium solar activity. The planetary waves are transformed from the neutral to the ionized component adequately as for the period. It was proved that planetary wave type oscillations in the lower ionosphere are caused by the neutral atmosphere oscillations, not by solar or geomagnetic activity. Various features of planetary wave activity, inferred from ionospheric measurements, have been studied. Perhaps the most interesting results are those on long-term trends. A general increase of planetary wave activity has been observed in the 1970s and 1980s, while the level of planetary wave activity has been stable in the 1960s and 1990s.</div>","PeriodicalId":101026,"journal":{"name":"Physics and Chemistry of the Earth, Part C: Solar, Terrestrial & Planetary Science","volume":"26 6","pages":"Pages 381-386"},"PeriodicalIF":0.0,"publicationDate":"2001-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S1464-1917(01)00018-6","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79646489","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: 18

Natural hazard assessment using GIS and remote sensing methods, with particular reference to the landslides in the Wondogenet Area, Ethiopia 利用地理信息系统和遥感方法进行自然灾害评估，特别是埃塞俄比亚Wondogenet地区的滑坡

Physics and Chemistry of the Earth, Part C: Solar, Terrestrial & Planetary Science Pub Date : 2001-01-01 Epub Date: 2001-09-17 DOI: 10.1016/S1464-1917(01)00065-4

B. Temesgen , M.U. Mohammed , T. Korme

引用次数: 163

On volatile particle formation in aircraft exhaust plumes 飞机废气中挥发性微粒的形成

Physics and Chemistry of the Earth, Part C: Solar, Terrestrial & Planetary Science Pub Date : 2001-01-01 Epub Date: 2001-09-17 DOI: 10.1016/S1464-1917(01)00047-2

A. Sorokin, X. Vancassel, P. Mirabel

引用次数: 9

A national network for snow monitoring in Norway: Snow pillow verification using observations and models 挪威全国积雪监测网络:利用观测和模式验证雪枕

Physics and Chemistry of the Earth, Part C: Solar, Terrestrial & Planetary Science Pub Date : 2001-01-01 Epub Date: 2002-02-14 DOI: 10.1016/S1464-1917(01)95016-0

H.K. Sorteberg, R.V. Engeset, H.C. Udnæs

{"title":"A national network for snow monitoring in Norway: Snow pillow verification using observations and models","authors":"H.K. Sorteberg, R.V. Engeset, H.C. Udnæs","doi":"10.1016/S1464-1917(01)95016-0","DOIUrl":"10.1016/S1464-1917(01)95016-0","url":null,"abstract":"<div>Snowmelt makes a substantial contribution to spring floods in Norway. The most severe floods, such as the flood in southeast Norway in 1995, are fed from extensive snowcovered high-mountain areas. However, monitoring of the temporal and spatial variability of snow on a real-time basis is particularly difficult due to the vast extent, remote location and high-frequency variability of snow. To monitor the temporal evolution of the snow mass and its water content during winter and spring, a network of 23 snow pressure pillows has been established in Norway, covering 58°N–71°N, 6°E–28°E, and 30–1400 m above sea level. Hourly data are supplied twice a day to government agencies.During the 1998/1999 winter and spring, extensive manual sampling was conducted on a monthly basis to verify the measurements obtained from the snow pillows. Furthermore, nearby meteorological data were used to simulate snow accumulation and ablation using a snow model. To investigate the performance of the snow pillow network, manual snow surveys (depth and density, liquid water, stratigraphy and grain size), snow models (SWE, snow runoff, LWC) and nearby air temperature and precipitation data were analysed. The results are important for snow pillow deployment and maintenance, as well as snowmodelling in terms of historical simulations and spatial-temporal variation in model performance and parameter settings. The results show that snow accumulation was well simulated using the model. Snowmelt was not so easy to simulate. The snow pillow performance was not as good as expected, and it was obvious that the snow pillows did not respond well during periods of repeated melting and refreezing. Discrepancies were also observed between snow pillow and manual observations during the melting period in spring, which may be attributable to difficulties during the snow survey sampling.</div>","PeriodicalId":101026,"journal":{"name":"Physics and Chemistry of the Earth, Part C: Solar, Terrestrial & Planetary Science","volume":"26 10","pages":"Pages 723-729"},"PeriodicalIF":0.0,"publicationDate":"2001-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S1464-1917(01)95016-0","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74873046","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: 22