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?trmm多卫星测雨数据在赣江上游径流模拟中的应用  [PDF]
?袁飞,赵晶晶,任立良,江善虎,周瑜佳,尹智力
天津大学学报(自然科学与工程技术版) , 2013, DOI: 10.11784/tdxb20130707
Abstract: ?选取赣江上游峡山站以上集水区域为研究区域,以雨量站观测数据为基准数据,评估热带降雨观测计划trmm-3b42v6降水数据的精度,并采用上述2种降水数据驱动栅格型新安江模型,模拟赣江峡山站日流量和月流量过程.结果表明,尽管trmm日降水数据较雨量站数据存在较大偏差,但采用trmm降水数据模拟的日流量能基本再现峡山站的日流量过程;trmm月降水数据精度较高,能够较为精确地模拟峡山站的月流量过程.因此trmm月降水数据可应用于赣江流域的降雨-径流过程模拟,在无资料地区的水文预报、水资源估算、水资源评价与规划等相关研究领域具有广阔的应用前景.
trmm测雨产品3b42与台站资料在中国区域的对比分析  [PDF]
骆三,苗峻峰,牛涛,魏春秀,王霞
气象 , 2011, DOI: 10.7519/j.issn.1000-0526.2011.9.004
Abstract: 本文利用2004—2008年6—8月中国673个气象站逐6小时降水资料检验同期trmm测雨产品3b42的精度。经检验得出:卫星资料日平均降水和降水频率空间分布与台站资料非常类似,相关系数分别能达到0.79和0.84,降水频率与台站资料相比偏大;从日降水相关空间分布看,卫星资料在东部地区相关性较高,日降水相关系数都在0.6~0.9之间;从日降水和逐6小时降水平均绝对误差空间分布看,卫星资料在华南地区误差最大,长江流域次之;从中国8个区域逐6小时降水总量日变化看,卫星资料与台站资料有很好的一致性,但在华南地区20时降水量偏小;按不同雨量等级对比,发现卫星资料绝对误差相对百分率空间分布有如下特点:小雨全国普遍数值偏高,中雨东部部分地区偏大,大雨和暴雨整体上数值小于1;全国平均漏演率和空演率分别为10%和14%。
用华南暴雨试验雨量资料对trmm/tmi-85.5ghz测雨能力的考察  [PDF]
吕艳彬?,顾雷?,李亚萍?,高慧林?,邵明轩?,陶祖钰?
热带气象学报 , 2001,
Abstract: 利用华南暴雨试验期间稠密的雨量资料对热带测雨卫星(trmm)微波成像仪(tmi)频率为85.5ghz(波长0.35cm)的测雨能力进行了考察。通过tmi-85.5ghz亮温分布和一小时雨量分布的对比发现,对流性降水的强雨量中心与tmi-85.5ghz亮温的低值区有很好的对应关系,雨带分布和低亮温分布的位置及形状都很相似,雨强的大小和亮温的关系也相当密切:雨强越大,亮温值越低。亮温数值和雨强(指每小时雨量,下同)的相关统计进一步表明:雨强的大小与亮温呈明显的负相关,特别是当雨强达到或超过7mm/h时的相关程度非常显著,从而确认了tmi-85.5ghz的微波遥感对对流性强降水有较好的测雨能力。
Physical and chemical indicators of soil health diagnostics and its application
土壤质量诊断与评价理化指征及其应用

Hu Chun-sheng,
胡春胜

中国生态农业学报 , 1999,
Abstract: 介绍了澳大利亚科工组织建立的流域健康诊断指征体系的指征选择原则、13项诊断指征、指征评 价方法与评价过程。并以此方法筛选和评价出太行山前平原农田土壤质量诊断的理化指征,提出了以经验性指征、形态学与物理学指征和化学指征综合评价该区土壤质量的指征体系。
土家医唯阳论  [PDF]
洪宗国
中南民族大学学报(自然科学版) , 2014,
Abstract: 从中医药阴阳的概念出发,导出了土家医阳主阴从的唯阳论的基本内容,研究了土家医唯阳论在生理与病理上的表现,介绍了土家医对阳病的分类,总结了土家医治疗不同阳病的方法与药物. 认为唯阳论在土家医药理 论体系中具有主导的意义.
Accounting for Uncertainties of the TRMM Satellite Estimates  [PDF]
Amir AghaKouchak,Nasrin Nasrollahi,Emad Habib
Remote Sensing , 2009, DOI: 10.3390/rs1030606
Abstract: Recent advances in the field of remote sensing have led to an increase in available rainfall data on a regional and global scale. Several NASA sponsored satellite missions provide valuable precipitation data. However, the advantages of the data are limited by complications related to the indirect nature of satellite estimates. This study intends to develop a stochastic model for uncertainty analysis of satellite rainfall fields through simulating error fields and imposing them over satellite estimates. In order to examine reliability and performance of the presented model, ensembles of satellite estimates are simulated for a large area across the North and South Carolina. The generated ensembles are then compared with original satellite estimates with respect to statistical properties and spatial dependencies. The results show that the model can be used to describe the uncertainties associated to TRMM multi-satellite precipitation estimates. The presented model is validated using random sub-samples of the observations based on the bootstrap technique. The results indicate that the model performs reasonably well with different numbers of available rain gauges.
阳射线研究简史  [PDF]
肖明,杨建邺
物理 , 1994,
Abstract: ?人们在回顾气体放电研究的历史时,对阴极射线作过详尽的探讨,但对阳射线(positiverays)研究的历史,却很少有人注意,实际上,这段鲜为人知的历史,对原子物理学的进展,有着极为重要的意义,本文所讨论的正是这项研究的简要历史。一、阳射线的早期研究1886年,德国物理学家戈德斯坦(e。go?...
Tropical Precipitation Estimated by GPCP and TRMM PR Observations
LI Rui,FU Yunfei,
LI Rui
,FU Yunfei

大气科学进展 , 2005,
Abstract: In this study, tropical monthly mean precipitation estimated by the latest Global Precipitation Climatology Project (GPCP) version 2 dataset and Tropical Rainfall Measurement Mission Precipitation Radar (TRMM PR) are compared in temporal and spatial scales in order to comprehend tropical rainfall climatologically. Reasons for the rainfall differences derived from both datasets are discussed. Results show that GPCP and TRMM PR datasets present similar distribution patterns over the Tropics but with some differences in amplitude and location. Generally, the average difference over the ocean of about 0.5 mm d-1 is larger than that of about 0.1 mm d-1 over land. Results also show that GPCP tends to underestimate the monthly precipitation over the land region with sparse rain gauges in contrast to regions with a higher density of rain gauge stations. A Probability Distribution Function (PDF) analysis indicates that the GPCP rain rate at its maximum PDF is generally consistent with the TRMM PR rain rate as the latter is less than 8 mm d-1. When the TRMM PR rain rate is greater than 8 mm d-1, the GPCP rain rate at its maximum PDF is less by at least 1 mm d-1compared to TRMM PR estimates. Results also show an absolute bias of less than 1 mm d-1 between the two datasets when the rain rate is less than 10 mm d-1. A large relative bias of the two datasets occurs at weak and heavy rain rates.
Characteristics of Rainfall Structure over the Tropical Pacific during the Later Period of 1997/1998 El Ni(n)o Derived from TRMM PR Observations
利用热带测雨卫星的测雨雷达资料对1997/1998年El Ni?o后期热带太平洋降水结构的研究

LI Rui,FU Yun-Fei,ZHAO Ping,
李锐
,傅云飞,赵萍

大气科学 , 2005,
Abstract: 利用热带测雨卫星的测雨雷达(TRMM PR)的探测结果,对1997/1998年 El Ni(n)o后期热带太平洋的降水结构进行了研究,并对比了非El Ni(n)o的1999年和2000年的同期降水情况,取得如下结果:(1)1997/1998 El Ni(n)o后期与非El Ni(n)o期间相比,1997/1998 El Ni(n)o后期,热带东、中太平洋层云降水和对流云降水的比例明显增大、平均降水率也增大,并且层云强降水的比例增多,而层云弱降水比例减少.(2)在非El Ni(n)o期间,热带东、中太平洋对流云降水系统较为浅薄,冻结层高度比西太平洋低约0.5 km;而在1997/1998 El Ni(n)o后期,这种差异明显减小,热带东、中太平洋对流云降水和层云降水都变得深厚;对流云降水和层云降水的降水率随高度的变化也发生了变化.(3)对大气环流的分析表明,对应于降水结构的变化,热带太平洋地区的高空辐合辐散分布也发生了改变,导致Walker环流在1997/1998 El Ni(n)o后期减弱.
Dynamic Hydrological Modeling in Drylands with TRMM Based Rainfall  [PDF]
Elena Tarnavsky,Mark Mulligan,Mohamed Ouessar,Abdoulaye Faye,Emily Black
Remote Sensing , 2013, DOI: 10.3390/rs5126691
Abstract: This paper introduces and evaluates DryMOD, a dynamic water balance model of the key hydrological process in drylands that is based on free, public-domain datasets. The rainfall model of DryMOD makes optimal use of spatially disaggregated Tropical Rainfall Measuring Mission (TRMM) datasets to simulate hourly rainfall intensities at a spatial resolution of 1-km. Regional-scale applications of the model in seasonal catchments in Tunisia and Senegal characterize runoff and soil moisture distribution and dynamics in response to varying rainfall data inputs and soil properties. The results highlight the need for hourly-based rainfall simulation and for correcting TRMM 3B42 rainfall intensities for the fractional cover of rainfall (FCR). Without FCR correction and disaggregation to 1 km, TRMM 3B42 based rainfall intensities are too low to generate surface runoff and to induce substantial changes to soil moisture storage. The outcomes from the sensitivity analysis show that topsoil porosity is the most important soil property for simulation of runoff and soil moisture. Thus, we demonstrate the benefit of hydrological investigations at a scale, for which reliable information on soil profile characteristics exists and which is sufficiently fine to account for the heterogeneities of these. Where such information is available, application of DryMOD can assist in the spatial and temporal planning of water harvesting according to runoff-generating areas and the runoff ratio, as well as in the optimization of agricultural activities based on realistic representation of soil moisture conditions.
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