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1.
起伏地形下黄河流域太阳直接辐射分布式模拟 总被引：11，自引：0，他引：11
基于数字高程模型(DEM)数据和气象站观测资料建立了起伏地形下太阳直接辐射分布式计算模型,模型充分考虑了地形因子(坡向、坡度、地形相互遮蔽)对起伏地形下太阳直接辐射空间分布的影响;以1km×1km分辨率的DEM数据作为地形的综合反映,计算了起伏地形下黄河流域1km×1km分辨率太阳直接辐射的空间分布;深入分析了起伏地形下太阳直接辐射受地理、地形因子影响的变化规律。结果表明:受地形起伏和坡向、坡度等局地地形因子的影响,山区年太阳直接辐射量的空间差异比较明显,向阳山坡(偏南坡)的年直接辐射量明显高于背阴山坡(偏北坡) 相似文献
2.
基于数字高程模型(DEM)数据和气象站观测资料建立了起伏地形下太阳直接辐射分布式计算模型,模型充分考虑了地形因子(坡向、坡度、地形相互遮蔽)对起伏地形下太阳直接辐射空间分布的影响;以1km×1km分辨率的DEM数据作为地形的综合反映,计算了起伏地形下黄河流域1km×1km分辨率太阳直接辐射的空间分布;深入分析了起伏地形下太阳直接辐射受地理、地形因子影响的变化规律.结果表明受地形起伏和坡向、坡度等局地地形因子的影响,山区年太阳直接辐射量的空间差异比较明显,向阳山坡(偏南坡)的年直接辐射量明显高于背阴山坡(偏北坡). 相似文献
3.
基于DEM的中国地形起伏度适宜计算尺度研究 总被引：10，自引：0，他引：10
基于SRTM和ASTER DEM数据,在全国范围内选取13个实验区,在渐变尺度下计算平均起伏度变化曲线的"突变点",据此确定中国地形起伏度的适宜计算尺度;结合山地界定标准计算各实验区山地面积,并采用人工解译的山地范围对计算结果进行检验。研究结果表明:1)地形起伏度适宜计算尺度与所采用的DEM数据有关,DEM分辨率越小,地形起伏度适宜计算尺度越大;2)针对同一分辨率DEM数据,中国境内的地形起伏度适宜计算尺度随地貌特征变化而变化,但总体变化幅度不大;3)针对SRTM和ASTER DEM两种常用数据源,分别选择4.72km2和3.20km2作为地形起伏度适宜计算尺度是合理的,山地界定精度达90%以上。 相似文献
4.
基于DEM的黄河流域天文辐射空间分布 总被引：23，自引：3，他引：23
基于1 km×1 km分辨率的数字高程模型(DEM) 数据,利用建立的起伏地形下天文辐射分布式计算模型,计算了黄河流域1 km×1 km分辨率各月天文辐射的空间分布。结果表明:局部地形对黄河流域年和四季天文辐射的空间分布影响明显;在太阳高度角较低的冬季,地理和地形因子对天文辐射的影响相当强烈,山区天文辐射的空间差异大,1月份向阳山坡(偏南坡) 天文辐射可为背阴山坡(偏北坡) 的2~3倍,极端天文辐射的差异可达10倍以上;而在太阳高度角较高的夏季,天文辐射空间差异较小,7月份不同地形极端天文辐射的差异仅在16%左右;四季中,地形对天文辐射影响的程度为冬季>秋季>春季>夏季。 相似文献
5.
贵州高原复杂地形下太阳总辐射精细空间分布 总被引：1，自引：0，他引：1
海拔、坡度、坡向以及周围地形遮蔽作用,造成山区各部位接受到的太阳辐射能有很大差异. 在前人研究的基础上,对以前的模型进行了一些改进,考虑了坡度、坡向和地形相互遮蔽作用对复杂地形下天文辐射的影响,基于数字高程模型(DEM)数据,研制了以复杂地形下天文辐射为起始数据的复杂地形下太阳总辐射的分布式模型,在模型中还考虑了散射辐射的各向异性及坡地反射辐射对复杂地形下太阳总辐射的影响.应用100 m×100 m分辨率的DEM数据及气象站常规观测气象资料,计算了贵州高原复杂地形下100 m×100 m分辨率的复杂地形下太阳总辐射.结果表明:(1) 局地地形因子如坡度、坡向、地形遮蔽等对太阳总辐射影响显著,地形对复杂地形下太阳总辐射的影响是不容忽视的.(2)在缺乏复杂地形下坡面考察资料的情况下,建立以常规气象站观测资料为主的物理经验统计模型是实现细网格辐射资源计算的可行途径. 相似文献
6.
天文辐射是辐射计算、太阳能资源评估及其他相关研究领域重要的起始参量,由于坡度、坡向和地形之间相互遮蔽等局地地形因子的影响,使实际起伏地形下获得的天文辐射与水平面上获得的天文辐射有一定差异。确定实际起伏地形下天文辐射是比较困难的。应用数字高程模型(DEM)数据和地理信息系统(G IS),建立起伏地形下天文辐射分布式计算模型,计算了起伏地形下贵州高原100 m×100 m分辨率天文辐射精细空间分布,分析了局地地形因子对起伏地形下天文辐射的影响。结果表明:(1)贵州高原起伏地形下天文辐射的空间分布具有明显的地域分布特征。(2)贵州高原起伏地形下天文辐射年总量平均为481.7~13 041.8 M J/m2,1月、7月天文辐射分别为0.0~1 244.7 M J/m2、0.0~1 264.8 M J/m2。(3)局地地形因子对起伏地形下天文辐射空间分布的影响随季节和纬度变化,虽然坡度、坡向和地形遮蔽对天文辐射的影响,在太阳高度角较低的1月比太阳高度角较高的7月相对较大,但因为7月水平面获得的天文辐射的强度相对较大,7月局地地形对天文辐射的影响依然显著。因此,贵州高原起伏地形对天文辐射的影响是不容忽视的。 相似文献
7.
任意地形实际天气条件下小时入射短波辐射模型——以黑河流域为例 总被引：3，自引：2，他引：1
建立了一个任意地形和实际天气条件下,能够计算大范围、长时间、高时空分辨率的太阳入射短波辐射模型,模型采用简化的辐射传输参数化方案和NCEP/NCAR资料相结合的方法,并成功应用于黑河流域2002年度每小时、1 km×1 km分辨率的总辐射、直接辐射和散射辐射的计算,所应用的地面资料仅为流域的地形信息。鉴于模型中总辐射是根据直接辐射和散射辐射推算的,而黑河流域2002年度缺乏直接辐射和散射辐射实测资料,模型采用分别位于黑河山区西水、中游临泽和下游额济纳旗3套自动观测仪器的总辐射资料进行验证,西水实测总辐射与计算总辐射的R2＝0.71,而临泽和额济纳旗R2分别为0.90和0.91,但各站点均出现部分结果相差很大的情况。出现地域差异和部分结果相差很大的主要原因是由于总云量资料时空分辨率低造成的,另外计算和实测数据空间尺度的不一致也部分造成山区计算效果较差。 相似文献
8.
贵州高原复杂地形下月平均日最高气温分布式模拟 总被引：4，自引：1，他引：3
在前人研究的基础上,对以前的模型进行改进,考虑了坡度、坡向和地形相互遮蔽作用对复杂地形下天文辐射的影响,基于数字高程模型(DEM)数据,建立以天文辐射为起始数据的复杂地形下月平均日最高气温的分布式模型,在模型中考虑了海拔高度、复杂地形下太阳总辐射、日照百分率对月平均日最高气温的影响.以贵州高原为例.应用100m×100m分辨率的DEM数据.1960-2000年贵州省及周边102个气象站常规气象要素观测资料以及NOAA-AVHRR观测资料,10个气象站的太阳辐射量资料,计算了贵州高原各月及年平均日最高气温精细空间分布.结果表明:(1)坡度、坡向、地形遮蔽对月平均日最高气温的影响较大,由于局地地形因子的影响,复杂地形下月平均日最高气温的空间分布具有明显的地域分布特征,局地地形对月平均日最高气温的影响是不容忽视的.(2)季节不同,局地地形因子对复杂地形下月平均日最高气温空间分布的影响不同,冬半年大于夏半年.月平均日最高气温随海拔高度的增加而降低.南坡随坡度的增大而升高:北坡随坡度的增大而降低.在坡向影响上,1-5月、10-12月偏北坡月平均日最高气温偏低,偏南坡月平均日最高气温偏高;7-8月因太阳高度较高,因此出现相反的情况.北坡高于南坡. 相似文献
9.
复杂地形下长江流域太阳总辐射的分布式模拟 总被引：1，自引：0，他引：1
利用长江流域气象站1960-2005年的观测资料(包括常规气象站点资料和辐射站点资料)、NOAA-AVHRR遥感数据(反演地表反照率),以1km×1km的数字高程模型(DEM)反映地形状况的主要数据,通过基于DEM数据的起伏地形下天文辐射模型和地形开阔度模型,分别建立了长江流域太阳直接辐射、散射辐射和地形反射辐射分布式模型,实现了长江流域太阳总辐射模拟,并对总辐射模拟结果进行了时空分布规律分析和对其受季节、纬度、地形因子(高度、坡度和坡向等)影响的局部规律分析,以及模拟结果的误差分析和站点验证分析。结果显示:太阳总辐射在季节上受影响的程度依次是春季>冬季>夏季>秋季;随着高度、坡度、纬度的增加,太阳总辐射受坡向影响的程度呈增强趋势,从坡向上看,向阳山坡(偏南坡)对太阳总辐射量明显高于背阴坡(偏北坡)。模拟的平均绝对误差为13.04177MJm-2,相对误差平均值3.655%,用站点验证方法显示:模拟绝对误差为22.667MJm-2,相对误差为4.867%。 相似文献
10.
天文辐射、干洁大气总辐射和湿洁大气总辐射是太阳辐射模拟的3种重要起始数据。依托Iqbal Model C和起伏地形下干/湿洁大气总辐射模型,实现了水平面和起伏地形下干/湿洁大气总辐射分布式模拟。以DEM数据作为地形的综合反映,结合常规气象资料,计算了水平面和起伏地形下中国1 km×1 km分辨率日天文辐射量、干洁大气总辐射量、湿洁大气总辐射量的空间分布,并对3种太阳辐射起始数据的时空分布特征做了对比分析。结果表明:3种辐射量均遵循随纬向变化的宏观分布规律;水平面干/湿洁大气总辐射量的分布体现了海拔的影响,水平面湿洁大气总辐射量的分布还体现了水汽分布的影响;起伏地形下的3种辐射量能很好的体现坡度、坡向和地形之间相互遮蔽等局部地形特征对辐射量的影响;以干/湿洁大气总辐射作为起始数据,将有助于提高太阳总辐射的模拟精度。 相似文献
11.
起伏地形下黄河流域太阳直接辐射分布式模拟 总被引：1，自引：0，他引：1
1 Introduction Directsolarradiation (DSR)isthe key com ponentofthe globalradiation reaching the Earth.For the influence of terrain factors,calculation of DSR quantity of rugged terrain is considerably com plex (Oliphantetal.,2003). The solarradiation quan… 相似文献
12.
Global solar radiation（GSR） is the most direct source and form of global energy, and calculation of its quantity is highly complex due to influences of local topography and terrain inter-shielding. Digital elevation model（DEM） data as a representation of the complex terrain and multiplicity condition produces a series of topographic factors（e.g. slope, aspect, etc.）. Based on 1 km resolution DEM data, meteorological observations and NOAA-AVHRR remote sensing data, a distributed model for the calculation of GSR over rugged terrain within the Yangtze River Basin has been developed. The overarching model permits calculation of astronomical solar radiation for rugged topography and comprises a distributed direct solar radiation model, a distributed diffuse radiation model and a distributed terrain reflectance radiation model. Using the developed model, a quantitative simulation of the GSR space distribution and visualization has been undertaken, with results subsequently analyzed with respect to locality and terrain. Analyses suggest that GSR magnitude is seasonally affected, while the degree of influence was found to increase in concurrence with increasing altitude. Moreover, GSR magnitude exhibited clear spatial variation with respect to the dominant local aspect; GSR values associated with the sunny southern slopes were significantly greater than those associated with shaded slopes. Error analysis indicates a mean absolute error of 12.983 MJm-2 and a mean relative error of 3.608%, while the results based on a site authentication procedure display an absolute error of 22.621 MJm-2 and a relative error of 4.626%. 相似文献
13.
Global solar radiation(GSR) is the most direct source and form of global energy, and calculation of its quantity is highly complex due to influences of local topography and terrain inter-shielding. Digital elevation model(DEM) data as a representation of the complex terrain and multiplicity condition produces a series of topographic factors(e.g. slope, aspect, etc.). Based on 1 km resolution DEM data, meteorological observations and NOAA-AVHRR remote sensing data, a distributed model for the calculation of GSR over rugged terrain within the Yangtze River Basin has been developed. The overarching model permits calculation of astronomical solar radiation for rugged topography and comprises a distributed direct solar radiation model, a distributed diffuse radiation model and a distributed terrain reflectance radiation model. Using the developed model, a quantitative simulation of the GSR space distribution and visualization has been undertaken, with results subsequently analyzed with respect to locality and terrain. Analyses suggest that GSR magnitude is seasonally affected, while the degree of influence was found to increase in concurrence with increasing altitude. Moreover, GSR magnitude exhibited clear spatial variation with respect to the dominant local aspect; GSR values associated with the sunny southern slopes were significantly greater than those associated with shaded slopes. Error analysis indicates a mean absolute error of 12.983 MJm-2 and a mean relative error of 3.608%, while the results based on a site authentication procedure display an absolute error of 22.621 MJm-2 and a relative error of 4.626%. 相似文献
14.
Min Liu András Bárdossy Jing Li Yuan Jiang 《International journal of geographical information science》2013,27(7):1281-1308
Solar radiation not only sustains the lives on the Earth, but also creates spatial and temporal variations of hydrological ingredients, such as vegetation, soil moisture, and snow. Precise quantification of spatial solar radiation incident on the Earth's surface which accounts for the topographic modulation, especially in complex terrain, underpins the study of many catchment hydro-meteorological and hydro-ecological processes. Topography is a key parameter that affects the spatial solar radiation pattern across different scales. This article addresses the issue of modelling spatial variability of actual solar radiation caused by topography from the hydrological perspective. Models with different algorithms and different complexities, from the simple empirical equations to process-based physical approach, have been developed to parameterize and calculate the potential radiation (under clear-sky condition) and the actual radiation (under overcast cloudy condition). Based on a review of the general steps of solar radiation modelling and the corresponding models for each step, two models with easily or globally available data for spatial solar radiation modelling in complex terrain, namely, the physically parameterized, remote-sensing-oriented Heliosat-2 model and the sunshine duration-based Angström–Prescott regression model are selected and implemented in a GIS framework. The capability of both models for simulation of cloudy-sky radiation on horizontal surfaces has been verified against observed station data showing an R 2 greater than 0.9. The validity of the models for modelling inclined surface is tested by comparing against each other, which has shown a satisfactory agreement and demonstrated that the simple Angström–Prescott method performed reasonably well compared with the more elaborate Heliosat-2 method. Scale sensitivity of the models and the shading effect are examined with different digital elevation model (DEM) resolutions from 30 to 500 m and reveal the existence of a threshold grid size to resolve the topography-induced spatial solar radiation variability. Spatial mapping of potential solar radiation and actual solar radiation has been demonstrated in a small catchment in Southern Germany, with a spatial difference up to 30% in winter and 5% in summer. This may lead to a significant difference for the energy-limited hydrological processes, such as snowmelt, and evapotranspiration. 相似文献
15.
TANGGuoan ZHAOMudan LITianwen LIUYongmei ZHANGTing 《地理学报(英文版)》2003,13(4):387-394
Slope is one of the crucial terrain variables in spatial analysis and land use planning, especially in the Loess Plateau area of China which is suffering from serious soil erosion. DEM based slope extracting method has been widely accepted and applied in practice. However slope accuracy derived from this method usually does not match with its popularity. A quantitative simulation to slope data uncertainty is important not only theoretically but also necessarily to applications. This paper focuses on how resolution and terrain complexity impact on the accuracy of mean slope extracted from DEMs of different resolutions in the Loess Plateau of China. Six typical geomorphologic areas are selected as test areas, representing different terrain types from smooth to rough. Their DEMs are produced from digitizing contours of 1:10,000 scale topographic maps. Field survey results show that 5 m should be the most suitable grid size for representing slope in the Loess Plateau area. Comparative and math-simulation methodology was employed for data processing and analysis. A linear correlativity between mean slope and DEM resolution was found at all test areas, but their regression coefficients related closely with the terrain complexity of the test areas. If taking stream channel density to represent terrain complexity, mean slope error could be regressed against DEM resolution (X) and stream channel density (S) at 8 resolution levels and expressed as(0.0015S2 0.031S-0.0325)X-0.0045S2-0.155S 0.1625, with a R2 value of over 0.98. Practical tests also show an effective result of this model in applications. The new development methodology applied in this study should be helpful to similar researches in spatial data uncertainty investigation. 相似文献
16.
不同分辨率DEM提取地面坡度的不确定性模拟:以在黄土高原的试验为例 总被引：1，自引：0，他引：1
Slope is one of the crucial terrain variables in spatial analysis and land use planning,especially in the Loess Plateau area of China which is suffering from serious soil erosion. DEM based slope extracting method has been widely accepted and applied in practice. However slope accuracy derived from this method usually does not match with its popularity. A quantitative simulation to slope data uncertainty is important not only theoretically but also necessarily to applications. This paper focuses on how resolution and terrain complexity impact on the accuracy of mean slope extracted from DEMs of different resolutions in the Loess Plateau of China. Six typical geomorphologic areas are selected as test areas, representing different terrain types from smooth to rough. Their DEMs are produced from digitizing contours of 1:10,000 scale topographic maps. Field survey results show that 5 m should be the most suitable grid size for representing slope in the Loess Plateau area. Comparative and math-simulation methodology was employed for data processing and analysis. A linear correlativity between mean slope and DEM resolution was found at all test areas,but their regression coefficients related closely with the terrain complexity of the test areas. If taking stream channel density to represent terrain complexity, mean slope error could be regressed against DEM resolution (X) and stream channel density (S) at 8 resolution levels and expressed as (0.0015S2+0.031S-0.0325)X-0.0045S2-0.155S+0.1625, with a R2 value of over 0.98. Practical tests also show an effective result of this model in applications. The new development methodology applied in this study should be helpful to similar researches in spatial data uncertainty investigation. 相似文献