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1.
针对天文、大气、宏观地理与局地地形等因子对起伏地形下太阳散射辐射的复杂作用,将影响起伏地形下太阳散射辐射的天空因素与地面因素分开处理.通过基于数字高程模型（DEM）数据的起伏地形下天文辐射模型和地形开阔度模型,综合考虑地面因素对散射辐射的影响;基于常规地面气象站观测资料建立的水平面散射辐射模型考虑天空因素对散射辐射的影响;依据各向异性散射机理,建立了起伏地形下太阳散射辐射分布式计算模型,探索出一条利用DEM数据和常规气象观测资料实现山区太阳散射辐射定量模拟的技术路线.以1 km×1 km分辨率的DEM数据作为地形的综合反映,实现了起伏地形下黄河流域1 km×1 km分辨率的太阳散射辐射分布式模拟. 相似文献
2.
李春来 任鑫 刘建军 邹小端 牟伶俐 王建宇 舒嵘 邹永廖 张洪波 吕昌 刘建忠 左维 苏彦 温卫斌 边伟 汪敏 许春 孔德庆 王晓倩 王芳 耿良 张舟斌 郑磊 朱新颖 李俊铎 欧阳自远 《中国科学:地球科学》2010,40(3):281-293
激光高度计是搭载在CE-1上的主要载荷之一, 用于月球表面的地形测量. 2007年11月28日02点22分, 激光高度计成功获得第一个探测数据, 截止到2008年12月4日, 总共获取了约912万个探测数据, 数据覆盖全月面. 我们利用这些探测数据制作了空间分辨率为3 km的全月DEM模型, 月表地形地貌特征反映明显, 地形细节表达层次分明、清晰可辨. DEM模型的平面定位精度为445 m (1σ), 高程测量精度为60 m (1σ). 根据这一DEM模型, 测得月球表面最大高差为19.807 km, 最高点位于Engel’gardt撞击坑东缘(158.656°W, 5.441°N, +10.629 km), 最低点位于Antoniadi撞击坑底部(172.413°W, 70.368°S, -9.178 km). 通过比较, CE-1的激光高度计DEM模型, 在精度和分辨率上明显优于美国ULCN2005, 与日本SELENE激光高度计DEM模型相当, 测量到的最高点与SELEN结果相似, 但CE-1数据新发现了比SELEN结果更低的最低点. 相似文献
3.
数字高程模型(DEM)是南极冰盖变化研究的基础,由于现场实测数据的稀缺,卫星测高数据是南极地区构建DEM的'主要数据来源.CryoSat-2是新一代用于极地冰盖、海冰监测的测高卫星,本文利用2012-12-2015-01两个完整周期的CryoSat-2测高数据建立一个新的南极冰盖DEM.坡度是影响卫星测高精度的重要因素之一,利用改进的重定位方法对CryoSat-2数据进行坡度改正.插值方法是影响DEM精度的重要因素,通过对几种常用插值方法的比较,最后选用克里金插值方法对测高数据进行插值,建立了1km分辨率的南极DEM.在88°S以南的CryoSat-2数据空白区,利用南极数字数据库(ADD)的等高线数据对DEM进行填补,建立了全南极冰盖DEM.利用ICESat卫星测高数据、IceBridge航空测高数据以及GPS地面实测数据对新建立的CryoSat-2 DEM进行精度验证,并与Bamber 1 km DEM、ICESat DEM、RAMPv2 DEM以及JLB97 DEM等四种国际上常用的南极DEM进行比较.结果表明:新建立的CryoSat-2 DEM的整体精度约为0.730±8.398 m;在冰弯顶部区域,DEM精度优于1 m;在冰架上,DEM精度约为4 m;在内陆冰盖大部分地区,DEM精度优于10 m;在地形复杂的山区和沿海边缘地区,DEM误差超过150 m. 相似文献
4.
复杂地形下黄河流域月平均气温分布式模拟 总被引：2，自引：0，他引：2
通过对常规气象站月平均气温资料的分析,发现在影响气温的众多因素中,海拔高度、太阳总辐射、地表长波有效辐射对气温具有显著影响.建立了月平均气温的物理经验统计模型,结合复杂地形下太阳总辐射分布式模拟结果,提出了依托常规地面气象观测资料实现复杂地形下月平均气温分布式模拟的方法,生成了黄河流域1km×1km分辨率月平均气温、月平均最高气温、月平均最低气温的空间分布图.分析表明,模拟结果能较好地反映气温的宏观分布趋势和局地分布特征.交叉验证结果表明,模型具有很好的稳定性,各月平均气温、月平均最高气温、月平均最低气温的模拟误差平均为0.19~0.35℃;加密站验证和个例年验证表明,模型具有良好的空间维和时间维模拟能力.提出的月平均气温分布式模型立足于常规地面气象观测资料,不依赖于山地野外考察资料,可以方便地在广大地区推广应用. 相似文献
5.
基于"嫦娥一号"激光测高数据的月球极区光照条件研究 总被引：1，自引：0，他引：1
月球极区光照模型为研究月球车着陆点选择和水冰存在的探测提供了依据.利用"嫦娥一号"探月卫星获取的激光测高数据,得到了全月面高精度的数字高程模型(DEM),特别是在月球两极地区,地形细节清晰可见,为极区光照模型的建立提供了精确的数据基础.本文通过由测高数据建立的DEM和月球轨道参数相结合,采用地形最大高度角法,对月球极区的光照条件及其应用进行了研究和分析.光照率的计算周期为19年,考虑了黄道和白道交点进动的影响(18.6年).计算结果表明:(1)未发现有持续光照区;(2)有长久阴影区存在;(3)在南极或北极的夏季,撞击坑边沿高地处可以享受到连续的光照;(4)Shackleton撞击坑可以作为月球车着陆的首选目标之一. 相似文献
6.
月球极区光照模型为研究月球车着陆点选择和水冰存在的探测提供了依据.利用“嫦娥一号”探月卫星获取的激光测高数据,得到了全月面高精度的数字高程模型(DEM),特别是在月球两极地区,地形细节清晰可见,为极区光照模型的建立提供了精确的数据基础.本文通过由测高数据建立的DEM和月球轨道参数相结合,采用地形最大高度角法,对月球极区的光照条件及其应用进行了研究和分析.光照率的计算周期为19年,考虑了黄道和白道交点进动的影响(18.6年).计算结果表明:(1)未发现有持续光照区;(2)有长久阴影区存在;(3)在南极或北极的夏季,撞击坑边沿高地处可以享受到连续的光照;(4) Shackleton撞击坑可以作为月球车着陆的首选目标之一. 相似文献
7.
8.
基于RS和GIS的建筑物空间分布格网化方法研究 总被引：1，自引：0，他引：1
本文在概述目前地震风险评估以及震后快速评估中建筑物空间分布格网化处理方法基础上, 提出了基于遥感和GIS的多源数据多因子建筑物空间分布格网化方法。 以云南省东川区为例, 利用DEM数据、 土地利用数据、 基础地理数据等, 提取地形、 地貌、 河流、 道路、 居民地和其他土地利用类型等各种影响因子, 以300 m格网为单元, 研究了建筑物空间分布与各类影响因子之间的相关性, 确定了各类子因子的建筑面积密度, 实现了建筑物空间分布格网化预测。 综合分析表明, 考虑多影响因子的建筑物空间非均匀性分布, 较传统的均匀性分布方法更接近真实空间分布, 因而有助于提高地震风险评估和震后快速损失评估的准确性。 相似文献
9.
为了更好地保证从中山站到DomeA的南极内陆冰盖考察,该考察路线沿线的地形信息是必需的．虽然Radarsat南极制图计划fRAMP）能提供迄今为止最高精度的全南极数字高程模型（DEM）,其最高水平分辨率为200m,但其真正的水平分辨率根据源数据的比例尺和区域覆盖密度不同而不同．对于冰架和内陆冰盖地区,水平精度约为5km．在东南极内陆冰盖地区和远离山脉地区该DEM的垂直精度估计为±50m,因此更高精度的地形数据还不存在．为了满足将来对地形信息更高精度的要求,由于ASTER光学影像具有高的空间分辨率05m）,而ICESat／GLAS测高数据有较高的高程精度（13．8cm）,因此本文融合ASTER立体数据和ICESat／GLAS测高数据提取了该考察路线高精度数字高程模型．首先选择一些测高数据点作为ASTER提取DEM过程中的高程控制,以减少匹配错误．由于从75°～81°S范围没有合格的ASTER立体数据覆盖,并且在该范围内ICESat轨道覆盖度大,观测数据比较密集,因此在该区域仅使用ICESat测高数据提取DEM,最后生成覆盖整条路线的DEM．分析结果表明DEM精度得到很大的提高,DEM的绝对垂直精度某些地区优于15m,除了影像009—001外,其余所有结果精度都在30m以内．其内部精度优于15m,某些情况下优于7m．生成的结果达到1：50000制图标准．结果表明在南极地区,综合利用各种遥感数据提取南极地区冰面地形信息是一种经济有效的手段． 相似文献
10.
复杂地形下黄河流域月平均气温分布式模拟 总被引：7，自引：0，他引：7
通过对常规气象站月平均气温资料的分析,发现在影响气温的众多因素中,海拔高度、太阳总辐射、地表长波有效辐射对气温具有显著影响．建立了月平均气温的物理经验统计模型,结合复杂地形下太阳总辐射分布式模拟结果,提出了依托常规地面气象观测资料实现复杂地形下月平均气温分布式模拟的方法,生成了黄河流域1km×lkm分辨率月平均气温、月平均最高气温、月平均最低气温的空间分布图．分析表明,模拟结果能较好地反映气温的宏观分布趋势和局地分布特征．交叉验证结果表明,模型具有很好的稳定性,各月平均气温、月平均最高气温、月平均最低气温的模拟误差平均为0．19～0．35℃;加密站验证和个例年验证表明,模型具有良好的空间维和时间维模拟能力．提出的月平均气温分布式模型立足于常规地面气象观测资料,不依赖于山地野外考察资料,可以方便地在广大地区推广应用． 相似文献
11.
采用2000~2004年中国地区34个台站的地磁日均值数据, 计算了通日和静日的平均年变率,以及静日的拟合年变率.应用上述年变率, 建立了2000.0~2005.0年代中国地区地磁场长期变化泰勒多项式模型和曲面样条模型.分析讨论了该泰勒多项式模型和曲面样条模型与国际地磁参考场长期变化模型(IGRF-SV)的异同, 结果表明,中国地区地磁长期变化的泰勒多项式模型与曲面样条模型的形态与数值是一致的,而且与IGRF-SV长期变化的趋势也是一致的,但中国地区地磁长期变化具有区域特征. 相似文献
12.
西沙地块作为在南海形成演化过程中形成的微陆块,记录了南海演化历史的重要信息,其地壳结构、物质组成及构造属性是探讨南海形成演化的关键.基于采集到的OBS2013-3测线海底地震仪数据,用射线追踪和正演走时拟合方法,获得了西沙地块的二维纵波速度模型.模型显示沉积层速度为2.2~3.2km·s-1,厚度为0.8~3.0km,局部基底面起伏较大,上地壳顶部速度为5.0~5.5km·s-1,下地壳底部速度为6.9km·s-1,上地幔顶部速度为8.0km·s-1.西沙地块的地壳厚度平均为23km,上地壳厚度约为9km,下地壳厚度约为14km,莫霍面埋深为23~27km.从穿过西沙地块的纵、横两条大剖面推算,块体大小约为9.2×105 km3,与华南陆缘相比,表现为整体减薄的陆壳特征.西沙地块与南沙地块垂直于西南次海盆扩张脊分布,根据二者地壳结构的特征对比,二者互为共轭关系. 相似文献
13.
For better prediction and understanding of land-atmospheric interaction, in-situ observed meteorological data acquired from the China Meteorological Administration (CMA) were assimilated in the Weather Research and Forecasting (WRF) model and the monthly Green Vegetation Coverage (GVF) data, which was calculated using the Normalized Difference Vegetation Index (NDVI) of the Earth Observing System Moderate-Resolution Imaging Spectroradiometer (EOS-MODIS) and Digital Elevation Model (DEM) data of the Shuttle Radar Topography Mission (SRTM) system. Furthermore, the WRF model produced a High-Resolution Assimilation Dataset of the water-energy cycle in China (HRADC). This dataset has a horizontal resolution of 25 km for near surface meteorological data, such as air temperature, humidity, wind vectors and pressure (19 levels); soil temperature and moisture (four levels); surface temperature; downward/upward short/long radiation; 3-h latent heat flux; sensible heat flux; and ground heat flux. In this study, we 1) briefly introduce the cycling 3D-Var assimilation method and 2) compare results of meteorological elements, such as 2 m temperature and precipitation generated by the HRADC with the gridded observation data from CMA, and surface temperature and specific humidity with Global Land Data Assimilation System (GLDAS) output data from the National Aeronautics and Space Administration (NASA). We find that the simulated results of monthly 2 m temperature from HRADC is improved compared with the control simulation and has effectively reproduced the observed patterns. The simulated special distribution of ground surface temperature and specific humidity from HRADC are much closer to GLDAS outputs. The spatial distribution of root mean square errors (RMSE) and bias of 2 m temperature between observations and HRADC is reduced compared with the bias between observations and the control run. The monthly spatial distribution of surface temperature and specific humidity from HRADC is consistent with the GLDAS outputs over China. This study could improve the land surface parameters by utilizing remote sensing data and could further improve atmospheric elements with a data assimilation system. This work provides an effective attempt at combining multi-source data with different spatial and temporal scales into numerical simulations, and the simulated results could be used in further research on the long-term climatic effects and characteristics of the water-energy cycle over China. 相似文献
14.
Motovilov Yu. G. Bugaets A. N. Gartsman B. I. Gonchukov L. V. Kalugin A. S. Moreido V. M. Suchilina Z. A. Fingert E. A. 《Water Resources》2018,45(1):128-134
A physically based model of runoff formation with daily resolution has been developed for the upper part of the Ussuri basin with an area of 24400 km2 based on ECOMAG hydrological modeling platform. Two versions of the hydrological model have been studied: (1) a crude version with the spatial schematization of the drainage area and river network based on DEM 1 × 1 km with the use of soil and landscape maps at a scale of 1: 2500000 and (2) a detailed version with DEM 80 × 80 m and soil and landscape maps of the scale of 1: 100000. Each version of the model has been tested for two variants of meteorological inputs: (1) meteorological forcing data (temperature, air humidity, precipitation) at eight weather stations and (2) with the involvement of additional data on precipitation collected at 15 gages in the basin. The model has been calibrated and validated over a 34-year period (1979–2012) with the use of runoff data for the Ussuri R. and its tributaries. The results of numerical experiments for assessing the sensitivity of model hydrological response to the spatial resolution of land surface characteristics and the density of precipitation gaging stations are discussed. 相似文献
15.
Distributed modeling of monthly air temperatures over the rugged terrain of the Yellow River Basin 总被引：1，自引：0，他引：1
Our analyses of the monthly mean air temperature of meteorological stations show that altitude, global solar radiation and
surface effective radiation have a significant impact on air temperature. We set up a physically-based empirical model for
monthly air temperature simulation. Combined the proposed model with the distributed modeling results of global solar radiation
and routine meteorological observation data, we also developed a method for the distributed simulation of monthly air temperatures
over rugged terrain. Spatial distribution maps are generated at a resolution of 1 km×1 km for the monthly mean, the monthly
mean maximum and the monthly mean minimum air temperatures for the Yellow River Basin. Analysis shows that the simulation
results reflect to a considerable extent the macro and local distribution characteristics of air temperature. Cross-validation
shows that the proposed model displays good stability with mean absolute bias errors of 0.19°C–0.35°C. Tests carried out on
local meteorological station data and case year data show that the model has good spatial and temporal simulation capacity.
The proposed model solely uses routine meteorological data and can be applied easily to other regions.
Supported by China Meteorological Administration key Project on New Technique Diffusion (Grant No. CMATG2006Z10) and Jiangsu
Key Laboratory of Meteorological Disasters (Grant No. KLME050102) 相似文献
16.
SimonWU JonathanLI GordonHUANG G.M.ZENG 《国际泥沙研究》2004,19(1):28-36
The horizontal accuracy of topographic data represented by digital elevation model (DEM) resolution brings about uncertainties in landscape process modeling with raster GIS. This paper presents a study on the effect of topographic variability on cell-based empirical estimation of soil loss and sediment transport. An original DEM of 10m resolution for a case watershed was re-sampled to three realizations of higher grid sizes for a comparative examination. Equations based on the USLE are applied to the watershed to calculate soil loss from each cell and total sediment transport to streams. The study found that the calculated total soil loss from the watershed decreases with the increasing DEM resolution with a linear correlation as spatial variability is reduced by cell aggregation. The USLE topographic factors (LS) extracted from applied DEMs represent spatial variability, and determine the estimations as shown in the modeling results. The commonly used USGS 30m DEM appears to be able to reflect essential spatial variability and suitable for the empirical estimation. The appropriateness of a DEM resolution is dependent upon specific landscape characteristics, applied model and its parameterization. This work attempts to provide a general framework for the research in the DEM-based empirical modeling. 相似文献
17.
The quality of digital elevation model (DEM)‐derived river drainage networks (RDNs) is influenced by DEM quality, basin physical characteristics, scale, and algorithms used; these factors should not be neglected. However, few research studies analyse the different evaluation approaches used in the literature with respect to adequacy, meaning of the results, advantages, and limitations. Focusing on coarse‐resolution networks, this paper reviews the use of these techniques and offers new insights on these issues. Additionally, we propose adaptations for selected metrics and discuss distinct interpretations for the evaluation of RDNs derived at different spatial resolutions (1, 5, 10, 20, and 30 km) considering the Uruguay River basin (206,000 km2) as a case study. The results demonstrate that lumped basin/river characteristics and basin delineation analysis should not be used as evaluation criteria for RDN quality; however, some of these metrics offer useful complementary information. Percentage of the DEM‐derived RDN within a uniform buffer placed around a river network considered as reference and mean separation distance between these two networks are more suitable metrics, but the former is insensitive to serious errors. The change in reference from a fine‐scale network to a coarse‐resolution manual tracing network significantly augments the discrepancy of these largest errors when the mean distance metric was applied, and visual comparison analysis is necessary to interpret the results for other metrics. We recommend the use of the mean distance metric in combination with a detailed visual assessment, the importance of which increases as the resolution coarsens. In both cases, the impact of network quality can be further refined by quantifying the basin shape and river length errors. 相似文献
18.
AbstractAn integrated model, combining a surface energy balance system, an LAI-based interception model and a distributed monthly water balance model, was developed to predict hydrological impacts of land-use/land-cover change (LUCC) in the East River basin, China, with the aid of GIS/RS. The integrated model is a distributed model that not only accounts for spatial variations in basin terrain, rainfall and soil moisture, but also considers spatial and temporal variation of vegetation cover and evapotranspiration (ET), in particular, thus providing a powerful tool for investigating the hydrological impact of LUCC. The model was constructed using spatial data on topography, soil types and vegetation characteristics together with time series of precipitation from 170 stations in the basin. The model was calibrated and validated based on river discharge data from three stations in the basin for 21 years. The calibration and validation results suggested that the model is suitable for application in the basin. The results show that ET has a positive relationship with LAI (leaf area index), while runoff has a negative relationship with LAI in the same climatic zone that can be described by the surface energy balance and water balance equation. It was found that deforestation would cause an increase in annual runoff and a decrease in annual ET in southern China. Monthly runoff for different land-cover types was found to be inversely related to ET. Also, for most of the scenarios, and particularly for grassland and cropland, the most significant changes occurred in the rainy season, indicating that deforestation would cause a significant increase in monthly runoff in that season in the East River basin. These results are important for water resources management and environmental change monitoring.
Editor Z.W. Kundzewicz 相似文献