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福建省区域尺度太阳总辐射模拟估算研究 总被引：1，自引：0，他引：1
比较了3种以常规地面气象资料为基础估算太阳总辐射的气候学估算模型(晴天辐射模型、天文辐射模型和MTCLIM气候模型),并以2004年福建省仅有的福州站和建瓯站太阳总辐射实测值进行验证.研究结果表明:以晴天总辐射为基值计算太阳总辐射估算模型的精度最高,运用该模型在ARCGIS支持下对福建省太阳总辐射进行空间插值,拟合了福建省区域尺度太阳总辐射月总量和年总量的空间分布,为省区域尺度生态系统碳循环模型,水文模型及植被净第一性生产力的估算研究提供了重要的空间表达参数. 相似文献
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P. E. GESSLER I. D. MOORE N. J. McKENZIE P. J. RYAN 《International journal of geographical information science》2013,27(4):421-432
Abstract Explicit and quantitative models for the spatial prediction of soil and landscape attributes are required for environmental modelling and management. In this study, advances in the spatial representation of hydrological and geomorphological processes using terrain analysis techniques are integrated with the development of a field sampling and soil-landscape model building strategy. Statistical models are developed using relationships between terrain attributes (plan curvature, compound topographic index, upslope mean plan curvature) and soil attributes (A horizon depth, Solum depth, E horizon presence/absence) in an area with uniform geology and geomorphic history. These techniques seem to provide appropriate methodologies for spatial prediction and understanding soil landscape processes. 相似文献
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J. A. Ruiz‐Arias D. Pozo‐Vázquez H. Alsamamra 《International journal of geographical information science》2013,27(8):1049-1076
Daily solar radiation estimates of four up‐to‐date solar radiation models (Solar Analyst, r.sun, SRAD and Solei‐32), based on a digital elevation model (DEM), have been evaluated and compared in a Mediterranean environment characterized by a complex topography. The models' estimates were evaluated against 40 days of radiometric data collected in 14 stations. Analyzed sky conditions ranged from completely overcast conditions to clear skies. Additionally, the role of the spatial resolution of the DEM has been evaluated through the use of two different resolutions: 20 and 100 m. Results showed that, under clear‐sky conditions, the daily solar radiation variability in the study area may be reasonably estimated with mean bias errors under 10% and root mean square error values of around 15%. On the other hand, results proved that the reliability of the estimates substantially decreases under overcast conditions for some of the solar radiation models. Regarding the role of the DEM spatial resolution, results suggested that the reliability of the estimates for complex topography areas under clear‐sky conditions improves using a higher spatial resolution. 相似文献
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地表太阳辐射是地球表层主要能量来源,对地表能量平衡、能量交换以及生态水文过程等具有决定性意义。山区地形复杂,其地表太阳辐射时空差异较大且较难估算。采用适用于山区的地表太阳辐射模型对西北昆仑山提孜那甫河流域地表太阳辐射时空分布进行了估算,分析了该流域季节太阳辐射空间分布规律并探讨了地形和云2个重要因素对太阳辐射空间分布的影响。结果表明:（1） 地形因子中周围地形阻挡即地形开阔度（Sky view factor,SVF）与年总太阳辐射的关系最为显著,太阳辐射随SVF增加而增加。（2） 年总太阳辐射随着高程增加首先减少,再而随之增加。探究SVF随高程的变化,发现其与太阳辐射随高程的变化趋势较为一致,因此在山区复杂地形下地表太阳辐射估算中仅利用高程对其校正存在明显不足,需综合考虑地形效应。（3） 研究计算了季节云出现频率空间分布与太阳辐射空间分布的相关系数,结果表明夏季太阳辐射受云影响较其他季节显著。定量分析了地形因子以及云对地表太阳辐射空间分布影响的贡献率,周围地形阻挡SVF对地表太阳辐射空间分布的影响最大,高程和云次之。因此综合考虑地形和云对太阳辐射的影响在山区太阳辐射模拟中是非常必要的,研究可为山区地表太阳辐射模拟提供理论依据,并为山区生态水文过程研究提供方法支撑。 相似文献
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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
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Modelling runoff and erosion for a semi-arid catchment using a multi-scale approach based on hydrological connectivity 总被引：1，自引：0，他引：1
Runoff and erosion processes are often non-linear and scale dependent, which complicate runoff and erosion modelling at the catchment scale. One of the reasons for scale dependency is the influence of sinks, i.e. areas of infiltration and sedimentation, which lower hydrological connectivity and decrease the area-specific runoff and sediment yield. The objective of our study was to model runoff and erosion for a semi-arid catchment using a multi-scale approach based on hydrological connectivity. We simulated runoff and sediment dynamics at the catchment scale with the LAPSUS model and included plot and hillslope scale features that influenced hydrological connectivity. The semi-arid Carcavo catchment in Southeast Spain was selected as the study area, where vegetation patches and agricultural terraces are the relevant sinks at the plot and hillslope scales, respectively. We elaborated the infiltration module to integrate these runoff sinks, by adapting the parameters runoff threshold and runoff coefficient, which were derived from a rainfall simulation database. The results showed that the spatial distribution of vegetation patches and agricultural terraces largely determined hydrological connectivity at the catchment scale. Runoff and sediment yield for the scenario without agricultural terraces were, respectively, a factor four and nine higher compared to the current situation. Distributed hydrological and erosion models should therefore take account of relevant sinks at finer scales in order to correctly simulate runoff and erosion-sedimentation patterns. 相似文献
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Improving solar radiation models is critical for supporting the increase in solar energy usage and modeling ecosystem dynamics. However, coarse spatial resolutions of solar radiation models overlook the impacts resulting from spatial variability of clouds at meso- and micro-scales. To address this problem, Moderate Resolution Imaging Spectroradiometer (MODIS) cloud climatology developed by the National Severe Storms Laboratory was used to relate cloudiness to surface solar radiation observations. We developed a linear regression model between the surface solar radiation and MODIS cloud climatology and used the model to estimate average radiation across Oklahoma. Furthermore, the study compared the average error and coefficient of determination to measured ground radiation. Error analysis of the regression model showed that the differences between observed radiation and estimated radiation were spatially autocorrelated for the Aqua MODIS satellite scan. This suggests cloudiness alone is not sufficient to predict surface solar radiation. This study found that simple cloud datasets alone can account for approximately 50% of the variation in observed solar radiation at 250-m spatial resolution, but additional datasets such as optical depth, elevation, and slope are needed to accurately explain spatial distributions of incoming shortwave radiation. 相似文献
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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
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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
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《地理学报(英文版)》2017,(11)
Geomorphometry,the science of digital terrain analysis(DTA),is an important focus of research in both geomorphology and geographical information science(GIS).Given that 70% of China is mountainous,geomorphological research is popular among Chinese scholars,and the development of GIS over the last 30 years has led to significant advances in geomorphometric research.In this paper,we review Chinese progress in geomorphometry based on the published literature.There are three major areas of progress:digital terrain modelling methods,DTA methods,and applications of digital terrain models(DTMs).First,traditional vector-and raster-based terrain modelling methods,including the assessment of uncertainty,have received widespread attention.New terrain modelling methods such as unified raster and vector,high-fidelity,and real-time dynamic geographical scene modelling have also attracted research attention and are now a major focus of digital terrain modelling research.Second,in addition to the popular DTA methods based on topographical derivatives,geomorphological features,and hydrological factors extracted from DTMs,DTA methods have been extended to include analyses of the structure of underlying strata,ocean surface features and even socioeconomic spatial structures.Third,DTMs have been applied to fields including global climate change,analysis of various typical regions,lunar surface and other related fields.Clearly,Chinese scholars have made significant progress in geomorphometry.Chinese scholars have had the greatest international impact in areas including high-fidelity digital terrain modelling and DTM-based regional geomorphological analysis,particularly in the Loess Plateau and the Tibetan Plateau regions. 相似文献
12.
J. H. Van Boxel Z. González-Carranza H. Hooghiemstra M. Bierkens M. I. Vélez 《Journal of Paleolimnology》2014,51(1):63-77
Knowledge of paleoclimates and past climate change is important to put recent and future climate change in perspective. In the absence of well-developed methodology to reconstruct paleoprecipitation the majority of climate reconstructions focus on temperature, whereas precipitation is an equally important climate parameter. This paper explores the possibility of inferring paleoprecipitation from lake-level records by inverse hydrological modelling. Pollen spectra of a lacustrine sediment core were used to infer changes in past temperatures and lake levels during the past 14,000 years. A hydrological model that calculates lake levels using meteorological parameters and a digital terrain model were developed for the catchment area of Lake La Cocha. After calibration the model accurately simulated modern lake levels. A sensitivity analysis shows that the model results are most sensitive to temperature and precipitation. This hydrological model was subsequently used to estimate mean annual precipitation needed to reproduce the pollen-based reconstructed lake levels (inverse modelling). The lake currently discharges through the permanent Guamués River, with a modelled mean annual discharge of 3.6 m3 s?1. However, past lake levels and hydrological modelling results suggest that Lake La Cocha has been free of discharge during most of the Holocene, and after an intermittent phase only recently started discharging permanently. The uncertainty in the inferred precipitation during the discharge-free period is estimated at ~22 mm. Quasi stable lake levels seem to justify using equilibrium conditions when reconstructing precipitation. Early Holocene lake levels were ~10 m lower than modern values, implying that precipitation must have been 30–40 % less than today. 相似文献
13.
分别利用分布式时变增益水文模型（DTVGM）和分布式耗水过程模型（DEPM）对延河流域延安水文站以上区域进行水文过程模拟,并应用拓展卡尔曼滤波(EKF)算法对2个模型的绿水(实际蒸散发)模拟结果进行同化处理,从而优化了研究区的绿水量并得出绿水的空间分布规律。结果表明：在整个模拟期,DTVGM的月尺度效率系数（NSCE）达到了0.83,水量平衡相对误差为-1.97%,模型能够较好地模拟研究区的水文过程;DEPM的水量平衡相对误差为-1.81%,能较好地模拟流域的水量平衡;DTVGM和DEPM模拟的流域2010年平均绿水量分别为378.52 mm和375.55 mm,空间分布格局相似。与站点观测值比较,DTVGM和DEPM模拟绿水的NSCE分别是0.76和0.59,DEPM的结果具有更多的空间变化信息。同化结果表明EKF算法能综合优化2个模型的模拟结果,同化后DTVGM模拟研究区的平均绿水量为376.34 mm,NSCE为0.78;同化后研究区绿水标准差为40.37 mm,比同化前增加了7.79 mm,绿水空间分布体现了更多的空间变化信息,同时,空间分布时格局也更加合理。 相似文献
14.
In mountainous area, spatial interpolation is the traditional method to calculate air temperature by use of observed temperature data. Due to lack of sufficient observation data in mountainous areas many precise interpolation methods could give only coarse result which could not meet the demand of precision agriculture and local climate exploration. Based on DEMs of 25 m resolution, a reversed model is constructed, with which temperature is simulated to the corresponding slope unit from the solar radiation. Taking Yaoxian county as a test area, and mean monthly temperature data as basic information sources, which are collected from 15 weather stations around Yaoxian county in Shaanxi province from the year of 1970 to 2000, a simulation for the solar radiation cell by cell is completed. By simulating solar radiation at each slope and flat cell unit, the terrain revised temperature model could be realized. A comparison between the simulated temperature and the radiation temperature from TM6 thermal infrared image shows that the terrain improved model gets a finer temperature distribution at local level. The accuracy of simulated temperature in mountainous area is higher than it is in flat area. 相似文献
15.
由于太阳辐射在山区的空间分布情况较为复杂,在Arcgis,Envi和C++基础上,提出了一个晴空条件下估算山区太阳辐射分布的模型。在借鉴国内外太阳辐射研究成果基础上充分考虑了地形因素和大气状况,利用Modtran大气辐射传输模型、DEM和Modis反照率数据建立了山区太阳辐射计算模型。以黑河上游山区为试验区,利用该模型模拟得到了黑河上游山区的太阳辐射,分析了坡度、坡向、海拔对太阳辐射空间分布的影响,并利用实测值对模型进行了验证,结果表明：该模型可较好地反映研究区内山区太阳总辐射的分布,可用于山区太阳辐射的估算。 相似文献
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Guonian LV Liyang XIONG Min CHEN Guoan TANG Yehua SHENG Xuejun LIU Zhiyao SONG Yuqi LU Zhaoyuan YU Ka ZHANG Meizhen WANG 《地理学报(英文版)》2017,27(11):1389-1412
Geomorphometry, the science of digital terrain analysis (DTA), is an important focus of research in both geomorphology and geographical information science (GIS). Given that 70% of China is mountainous, geomorphological research is popular among Chinese scholars, and the development of GIS over the last 30 years has led to significant advances in geomorphometric research. In this paper, we review Chinese progress in geomorphometry based on the published literature. There are three major areas of progress: digital terrain modelling methods, DTA methods, and applications of digital terrain models (DTMs). First, traditional vector- and raster-based terrain modelling methods, including the assessment of uncertainty, have received widespread attention. New terrain modelling methods such as unified raster and vector, high-fidelity, and real-time dynamic geographical scene modelling have also attracted research attention and are now a major focus of digital terrain modelling research. Second, in addition to the popular DTA methods based on topographical derivatives, geomorphological features, and hydrological factors extracted from DTMs, DTA methods have been extended to include analyses of the structure of underlying strata, ocean surface features and even socioeconomic spatial structures. Third, DTMs have been applied to fields including global climate change, analysis of various typical regions, lunar surface and other related fields. Clearly, Chinese scholars have made significant progress in geomorphometry. Chinese scholars have had the greatest international impact in areas including high-fidelity digital terrain modelling and DTM-based regional geomorphological analysis, particularly in the Loess Plateau and the Tibetan Plateau regions. 相似文献
17.
DEM流径算法的相似性分析 总被引：4，自引：0，他引：4
流径算法是分布式水文模型、土壤侵蚀模拟等研究中的关键技术环节,决定着汇水面积、地形指数等许多重要的地形、水文参数的计算。本文以黄土高原两个典型样区的不同分辨率DEM为研究对象,对常用的五种流径算法(D8、Rho8、Dinf、MFD和DEMON)通过相对差系数、累积频率图、XY散点分布图等进行了定量的对比分析。结果表明:算法的差异主要集中在坡面区域,汇流区域各类算法的差别较小;算法差异在不同DEM尺度下都有所体现,但高分辨率下的差异会更明显;在地形复杂区域,多流向算法要优于单流向算法。研究也进一步指出汇水面积、地形指数等水文参数对流径算法具有强烈的依赖性。 相似文献
18.
TOPMODEL中地形指数ln 的新算法 总被引：4，自引：0，他引：4
TOPMODEL中地形指数ln (α/tanβ)被用来近似表征流域径流源面积和地下水水位的空间分布特征,目前广泛使用的计算地形指数的方法为多流向算法 (FD8算法)。本文首先介绍了多流向算法的基本原理,并基于此对流动累积分配中的有效等高线长度精确计算提出了几何锥面内切圆算法,同时改进了传统的地形指数中单位等高线汇流面积α的计算方法,增强了多流向算法对DEM中异常栅格的处理能力。改进后的地形指数新算法在两个不同流域和不同分辨率DEM上与传统多流向算法进行了对比分析。结果表明新算法在原理上更符合地形指数物理意义,实际应用中其计算结果更准确。这种地形指数新算法的提出对于流域水文过程机理分析及陆面过程定量化研究具有一定的现实意义。 相似文献
19.
基于DEM的复杂地形流域特征提取 总被引：21，自引：2，他引：19
利用流域数字高程模型(DEM)构建数字水系模型并提取流域水系特征是分布式水文过程模拟的重要前提。提出了面向分布式水文过程模拟和流域特征提取的数字水系模型,并针对现有方法对复杂地形DEM中含有的平地、洼地及其嵌套情形的处理不足,提出了栅格水流分类、填洼分类与归并及有效填平处理、河谷平地的出流代价法构建栅格流向和流序等新的处理方法,并在开发的软件系统得到实现。使用该方法创建的黄土岭流域数字水系模型和提取的水系等流域特征结果表明:本文方法可有效应对复杂地形流域的处理,提取的流域水系特征与实际自然水系比较吻合,能够有效地消除现有方法在地形平坦区域容易产生的平行河道、奇异河道、河道变形等不足。 相似文献
20.
Terrain revised model for air temperature in mountainous area based on DEMs： A case study in Yaoxian county 总被引：1，自引：0，他引：1
YANG Xin TANG Guoan XIAO Chenchao DENG Fengdong 《地理学报(英文版)》2007,17(4):399-408
In mountainous area, spatial interpolation is the traditional method to calculate air temperature by use of observed temperature data. Due to lack of sufficient observation data in mountainous areas many precise interpolation methods could give only coarse result which could not meet the demand of precision agriculture and local climate exploration. Based on DEMs of 25 m resolution, a reversed model is constructed, with which temperature is simulated to the corresponding slope unit from the solar radiation. Taking Yaoxian county as a test area, and mean monthly temperature data as basic information sources, which are collected from 15 weather stations around Yaoxian county in Shaanxi province from the year of 1970 to 2000, a simulation for the solar radiation cell by cell is completed. By simulating solar radiation at each slope and flat cell unit, the terrain revised temperature model could be realized. A comparison between the simulated temperature and the radiation temperature from TM6 thermal infrared image shows that the terrain improved model gets a finer temperature distribution at local level. The accuracy of simulated temperature in mountainous area is higher than it is in flat area. 相似文献