Sub-Mesoscale Vortex Streets in the Region of the Shantar Islands (Sea of Okhotsk), According to Satellite Remote Sensing Data

Izvestiya, Atmospheric and Oceanic Physics - Images in the visible range of the MODIS Terra/Aqua and ETM+ Landsat 7/OLI Landsat 8 satellites are used to study vortex streets (VSes) in the region of...     

Assessment of Suspended Sediment Budget of the Lena River Delta Based on the Remote Sensing Dataset

Izvestiya, Atmospheric and Oceanic Physics - This study evaluates long-term and seasonal changes of sediment budget in Lena delta based on remote sensing dataset. Since 2000 Landsat images have...     

Open-Source Software Implementation and Validation of the Split-Window Method for Automated Land Surface Temperature Retrieval from Landsat 8 Data

Izvestiya, Atmospheric and Oceanic Physics - An open software implementation of the algorithm for retrieving the land surface temperature (LST) from Landsat 8 remote sensing satellite data is...     

Mapping Age Stages of Forest Vegetation Based on an Analysis of Landsat Multiseasonal Satellite Images

Izvestiya, Atmospheric and Oceanic Physics - The possibility of increasing the efficiency of forest vegetation mapping is studied using Landsat multitemporal satellite images of medium spatial...     

福建省海岛和海岸带遥感影像数据库构建与实现

在参考ISO19115-2003遥感影像元数据标准的基础上,利用覆盖福建全境的海岛、海岸带的Landsat7和SPOT5的原始影像、校正影像以及融合影像,构建基于SQL Server2005的福建省海岛、海岸带遥感影像数据库系统,实现了遥感影像元数据与影像数据的一体化存储与管理．同时,使用VB语言的可视化特性,实现了基于用户的可视化查询与下载．本系统的研发,将为福建省海岛、海岸带研究提供一个可以共享的基础数据平台．     

基于遥感图像分析的极区海冰漂移研究

自然水体中石油污染含量的时空间分布是数字地球领域水体环境研究的一个重要参数,利用遥感技术提取水中石油含量也是数字地球研究领域的一个热点问题.基于2009-2013年进行的六次石油类污水野外配比实验数据,结合2013年6月-2014年4月晴天获取的中国辽宁盘锦辽河油田Landsat 8/OLI遥感数据,在对配比实验测定值、Landsat 8/OLI传感器模拟值和Landsat 8/OLI传感器过境值等三类遥感反射比数据进行归一化处理的基础上,通过对波段特征进行分析,发现含油水样与无油水样在绿色、红色和近红外波段的遥感反射比存在明显的差异,由此提出了水体石油污染归一化遥感反射比指数NDPRI (Normalized Difference Petroleum Remote Sensing Reflectance Index),该指数可用来判断水体是否存在油污染,进一步建立利用NDPRI来反演水中石油含量遥感模式.结果表明:(1)含油水样和无油水样在蓝色波段的归一化遥感反射比差别不大;(2)含油水样在绿色和红色波段的归一化遥感反射比明显低于无油水样;(3)无油水样在近红外波段的归一化遥感反射比呈现下降趋势,而含油水样的归一化遥感反射比随着石油类浓度含量的增加而明显抬升,呈现出较好的线性关系;(4)含油水样,其NDPRI小于0.45,此阈值作为是否有油污染的判断值.最后,利用2014年4-8月污水厂获取的现场实测数据对模式进行验证,相对误差为13.5％,表明所建立的模式具有良好的石油含量反演精度.     

Spectral variations in upwelling radiant intensity in turbid coastal waters

The spectral characteristics of visible light upwelling from turbid coastal waters were examined separately by means of both in situ and remote optical sensors. Increasing concentrations of suspended sediment were found to be associated with a migration of the in situ peak in spectral intensity towards longer (red) wavelengths. The water colour changes at long wavelengths were preserved at satellite altitudes without significant degradation of the spectral shift by the atmosphere making it possible to interpret directly three commonly used Landsat algorithms in terms of the changes in the upwelling in situ spectra. It was determined that more than one Landsat algorithm was necessary to follow the spectral shift of the sediments. For suspended sediments in the Bay of Fundy in the concentration range 5–50 mg 1⁻¹, in situ, aircraft and satellite studies all indicated that a ratio of Landsat band 4 to band 5 was optimum for monitoring the spectral changes associated with the sediments. Successful use of the Landsat system was attributed to the high reflectance and optimum colour changes associated with the Bay of Fundy suspended sediments     

陆地卫星TM磁带资料在黄河口海区悬沙分布定量研究中的应用

遥感技术是目前获得河口地区及近海水域泥沙分布与扩散的有效方法,多采用美国Landsat系列的多光谱扫描仪(MSS)和专题制图仪(TM)、NOAA气象卫星、法国SPOT卫星资料和前苏联的联盟号以及我国的国土卫星资料等,即将发射的美国海洋卫星将为本项研究提供新的途径。资料的形式有磁带(CCT)和卫片两种,目前世界上以陆地卫星资料应用最广,这主要是由于它有资料商业化、易于获得、资料系列长、重复周期短、可监测动态変化及影像分辨率适中(MSS像元空间分辨率为80m,TM为30m)等优点。 河口区泥沙受河流径流、潮流、风浪等多种动力因素影响,悬浮泥沙的含量和颗粒组成经常变化,因而河口悬沙的时空分布及其运动规律较为复杂,用常规测量方法难以了解其变化规律,而遥感的多时相、多波段可监视泥沙扩散的动态变化;同时,陆地卫星图象覆盖面积较广(185×185k㎡),不同图幅的拼接、镶嵌技术也已完善,故可监测河口区泥沙扩散的空间变化。因此,遥感技术弥补了常规手段的费时、耗资、资料不同步、周期长、难以反映多变的黄河泥沙的动态变化等不足。本文根据1989年8月黄河口海区表层泥沙实测资料与天气条件大致相同的遥感资料(磁带)进行了相关分析,定量研究黄河泥沙入海后的扩散和分布规律。     

Delineating suspended sediment concentration patterns in surface waters of the Changjiang Estuary by remote sensing analysis

Three Landsat TM imageries (taken on 18 May 1987, 4 August 1998 and 28 July 2007) were used as the data source to identify the spatial and temporal variations of the suspended sediment concentration (SSC) in surface waters of the Changjiang Estuary. Atmospheric correction was carried out to determine the water-leaving reflectance using the FLAASH module. A regression equation between surveyed SSC and suspended sediment index was chosen to retrieve the SSC from the Landsat TM images. In addition, tidal harmonic analysis was performed to calculate tidal conditions corresponding to the acquisition time of satellite images. The results show that the SSC spatial patterns are similar to the in situ observation results, which show the highest SSC in the region of turbidity maximum zone in the Changjiang Estuary. For the period of 1987 to 2007, the SSC pattern is controlled mainly by tidal dynamic conditions and wind speeds, rather than sediment discharges from the river.     

陆地卫星相片的海岸带解译

海岸带是海洋与陆地交互作用的地带。海岸带的地貌和水文特征按潮汐海面可分为三带:高潮位以上的海滨,包括沿岸堤平原和海蚀阶地等,它们是古海洋作用的遗迹,一般不受现代海洋动力的影响,高潮位与低潮位之间的潮间带,它们随涨落潮而周期性地被淹;以及低潮位以下一直到波浪作用极限深度的水下岸坡,包括浅海和泻湖水域,属于水下环境。     

Analysis of the landscape structure in the tundra zone for western Siberia based on satellite data

The landscape structure are investigated for typical and southern tundra subzones of western Siberia based on satellite images from Landsat and WorldView. The microlandscape types for the considered regions are selected and areas of microlandscapes are defined on the basis of satellite information and accounting data of field studies. The areas of the main wetland landscapes in the different types of bogs in northwestern Siberia are defined.     

Atmospheric correction of Landsat data for the retrieval of sea surface temperature in coastal waters

1IntroductionRemote sensingis an effective approach for esti-mation of the sea surface temperature(SST),andadvanced very high resolution radiometer(AVHRR)and moderate resolution imaging spectroradiometer(MODIS)thermal infared(TIR)data are widelyused in th…     

Studying the dynamics of thermokarst lake fields in Altai mountain valleys

The dynamics of the thermokarst lake (TL) areas at six permafrost test sites (TSs) in Gorny Altai has been studied using the collection of the Landsat 5 asynchronical space images (1993–2010). It has been indicated that the average total lake area at all test sites increased by 31% during the studied period.     

苏北废黄河三角洲海岸时空演变遥感分析

基于遥感与地理信息系统技术,使用苏北废黄河三角洲海岸地区1978,1987和2000年的Landsat卫星遥感数据,选取岸线指标与波段,提取岸线信息,生成1978-1987年和1987-2000年海岸土地增减时空变化分布图,建立岸线变化距离及增速衡量指标,定量分析了废黄河三角洲海岸面积变化特征,以及灌河口-中山河口、中山河口-扁担港口和扁担港口-双洋河口以南岸段的时空变化格局与分布特征.研究结果表明,废黄河三角洲海岸的自然侵蚀速率呈减小趋势,但侵蚀作用仍在继续.侵蚀强度以废黄河口地区为中心,向南北两侧逐渐减弱.人工保滩护岸措施在一定程度上影响着自然侵蚀格局.其内部各岸段分别呈现缓蚀、侵蚀和基本侵淤平衡的变化格局.     

Spatial variations of tidal water level and their impact on the exposure patterns of tidal land on the central Jiangsu coast

The exposed area of intertidal zone varies with tidal water level changes. If intercomparisons of satellite images are adopted as a method to determine geomorphological changes of the intertidal zone in response to accretion or erosion processes, then the e?ect of water level variations must be evaluated. In this study, two Landsat TM images overpassing the central Jiangsu coastal waters on 2 January and 7 March 2002, respectively, were treated by the changing detection analysis using Image Di?erencing and Post-classiˉcation Comparison. The simultaneous tide level data from four tide gauge stations along the coast were used for displaying the spatial variations of water levels and determining the elevations of waterlines. The results show that the spatial variations of water levels are highly signiˉcant in the central Jiangsu coastal waters. The huge di?erences of tidal land exposure patterns between the two imaging times are related mainly to the spatial variations of tidal water levels, which are controlled by the di?erences in tidal phases for di?erent imaging times and the spatial variations of water level over the study area at each imaging time. Under complex tidal conditions, e.g., those of the central Jiangsu coastal waters, the tide-surge model should be used to eliminate e?ectively the e?ects of water level variations on remote sensing interpretation of geomorphological changes in the intertidal zone.     

多光谱遥感在长江口水深探测中的应用

利用L andsat-7 ETM 遥感图像反射率和实测水深值之间的相关性,建立了单波段模型、双波段模型、比值模型和多波段模型等4种线性回归模型,以及动量BP人工神经网络水深反演模型,对长江口南港航道水深进行了反演,对比分析了不同方法在长江口水深反演计算中的优劣性,试验表明,神经网络反演模型标准误差最小,精度最高。     

辽河口湿地景观格局变化特征与驱动机制分析

在GIS/RS技术与景观格局分析软件FRAGSTATS的支持下,利用1988、1995、2001和2007年的4期TM遥感影像数据,对辽河口地区的湿地景观格局的动态变化特征进行了定量分析。结果表明:自1988年以来,辽河口地区的湿地类型发生了重大变化,主要表现在大量的自然湿地转化为人工湿地或人工景观,具体表现在转化为建筑用地、水稻田、养殖区。驱动力分析表明:年平均气温升高,降水量的减少是导致辽河口地区湿地变化的主要自然因素;人口的急剧增长,经济开发等人类干扰是引起变化的主要驱动力。     

利用Landsat数据反演近岸海水表层温度的大气校正算法

介绍了一种将大气效应考虑在内、利用Landsat TM、ETM+热红外数据进行近海岸海表水温反演的单窗算法.在该算法中,将地表气温、相对湿度等常规气象资料作为初始参数,根据对流层中大气温度随高度呈线性降低、水汽随高度呈指数衰减的规律,建立了估算平均大气温度及水汽含量的通用模式.通过与实测数据及MODIS Terra海表水温产品比较发现,该算法能够提高运用TM/ETM+TIR单波段数据进行近岸海表水温(SST)反演的精度:一方面,反演所得结果更接近于海表实际水温;另一方面,它在一定程度上剔除大气中的水汽对SST反演的影响,进而提高海表水温的温度对比度.该提出的大气校正算法只需地表大气温度及相对湿度资料,该算法也无需进行大气模式的界定.     

绿潮Lansat影像滑动窗口自适应阈值全自动检测方法

Since the atmospheric correction is a necessary preprocessing step of remote sensing image before detecting green tide, the introduced error directly affects the detection precision. Therefore, the detection method of green tide is presented from Landsat TM/ETM plus image which needs not the atmospheric correction. In order to achieve an automatic detection of green tide, a linear relationship(y =0.723 x+0.504) between detection threshold y and subtraction x(x=λ_(nir)–λ_(red)) is found from the comparing Landsat TM/ETM plus image with the field surveys.Using this relationship, green tide patches can be detected automatically from Landsat TM/ETM plus image.Considering there is brightness difference between different regions in an image, the image will be divided into a plurality of windows(sub-images) with a same size firstly, and then each window will be detected using an adaptive detection threshold determined according to the discovered linear relationship. It is found that big errors will appear in some windows, such as those covered by clouds seriously. To solve this problem, the moving step k of windows is proposed to be less than the window width n. Using this mechanism, most pixels will be detected[n/k]×[n/k] times except the boundary pixels, then every pixel will be assigned the final class(green tide or sea water) according to majority rule voting strategy. It can be seen from the experiments, the proposed detection method using multi-windows and their adaptive thresholds can detect green tide from Landsat TM/ETM plus image automatically. Meanwhile, it avoids the reliance on the accurate atmospheric correction.     

1988—2015年马六甲海峡岸线时空变化特征分析

基于Landsat遥感影像,建立1988年、2000年和2015年3个时期马六甲海峡两侧的岸线数据,并从岸线结构、岸线变化速率、海陆格局和岸线开发利用强度等方面分析1988—2000年、2000—2015年和1988—2015年不同时段区域陆体以及槟城港等12个主要港口区域的岸线时空变化特征。结果如下:岸线结构变化显著,人工岸线长度和比例急剧增加,港口区域逐渐从单一类型主导向多元结构转变;除个别港口外,两侧岸线均呈向海扩张状态,南北两岸的岸线平均变化速率分别为0.91m/a和1.20m/a;因海峡南岸沼泽广布、地势低平及海平面上升等原因,其岸线稳定性差于海峡北岸;岸线开发利用强度持续增强,并表现出明显的海峡北岸强于南岸的空间差异,以及北岸第一阶段增长快于第二阶段,南岸第一阶段增长慢于第二阶段的时间差异。马六甲海峡的交通运输功能是两岸岸线变化的主要驱动因素。本研究对认识马六甲海峡两岸及港口区域岸线的时空变化和发展特征有重要意义,对海峡及港口岸线的综合管理具有一定借鉴作用。