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51.
该文报道碱厂废水随浓度变化的光谱实验。分析碱厂废水的光谱特征 ,并与相同浓度的海水悬浮泥沙水体的光谱进行比较 ;确定该废水特征波长为 50 1.3nm。根据光谱实验结果 ,结合当前已有的水色传感器的资料 ,选择两个卫星传感器波段 :Sea WIFS第四频道 (497.2~ 52 1.6 nm)和TM第二频道 (518.9~ 6 0 0 .2 nm) ;利用数字对 (R,c) ,建立了反射率与该污染水体浓度间的相关模式。为遥感技术大面积、快速地监测碱厂废水污染水体提供理论依据。  相似文献   
52.
Satellite-derived ocean color data of Coastal Zone Color Scanner (CZCS) on board the Nimbus-7 and Ocean Color and Temperature Scanner (OCTS) on board the Advanced Earth Observing Satellite (ADEOS) are jointly used with historical in situ data to examine seasonal and spatial distributions of chlorophyll a (Chl-a) and suspended particulate matter (SPM) concentrations in the East China Sea. Ocean color imagery showed that Chl-a concentrations on the continental shelf were higher than those of the Kuroshio area throughout the year. Satellite-derived Chl-a concentrations are generally in good accordance with historical in situ values during spring through autumn (although no shipboard in situ measurement was conducted at nearshore areas). In contrast, ocean color imagery in winter indicated high Chl-a concentrations (4–10 mg m–3) on the continental shelf where bottom depth was less than 50 m when surface water was turbid (2–72 g m–3 of SPM at surface), while historical in situ values were usually less than 1 mg m–3. This suggests that resuspended bottom sediment due to wind-driven mixing and winter cooling is responsible for the noticeable overestimation of satellite-derived Chl-a concentrations. The algorithm for ocean color needs to be improved urgently for turbid water.  相似文献   
53.
红树林遥感智能分类方法研究   总被引:13,自引:0,他引:13  
滕骏华  刘宇 《台湾海峡》1997,16(3):331-338
利用GIS信息中的红树林地域分布规律作向导,充分利用械树林区的光谱信息进行红树林植被信息提取。在对比研究常规的红树林图象自理方法的基础上,提出了适用于红树林植被信息遥感监测的智能分类方法。  相似文献   
54.
通过分析1980年以后的海冰资料和卫星云图照片,对黄、渤海沿岸11个海冰测点的历史变迁进行了评述,浅析了测点的优劣及使用资料时应注意的事项。  相似文献   
55.
The influences of mesoscale eddies on variations of the Kuroshio path south of Japan have been investigated using time series of the Kuroshio axis location and altimeter-derived sea surface height maps for a period of seven years from 1993 to 1999, when the Kuroshio followed its non-large meander path. It was found that both the cyclonic and anticyclonic eddies may interact with the Kuroshio and trigger short-term meanders of the Kuroshio path, although not all eddies that approached or collided with the Kuroshio formed meanders. An anticyclonic eddy that revolves clockwise in a region south of Shikoku and Cape Shionomisaki with a period of about 5–6 months was found to propagate westward along about 30°N and collide with the Kuroshio in the east of Kyushu or south of Shikoku. This collision sometimes triggers meanders which propagate over the whole region south of Japan. The eddy was advected downstream, generating a meander on the downstream side to the east of Cape Shionomisaki. After the eddy passed Cape Shionomisaki, it detached from the Kuroshio and started to move westward again. Sometimes the eddy merges with other anticyclonic eddies traveling from the east. Coalescence of cyclonic eddies, which are also generated in the Kuroshio Extension region and propagate westward in the Kuroshio recirculation region south of Japan, into the Kuroshio in the east of Kyushu, also triggers meanders which mainly propagate only in a region west of Cape Shionomisaki. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
56.
Seasonal and spatial variations of iceberg drift were studied using continuous satellite scatterometer images off Dronning Maud Land, East Antarctica. Generally, iceberg drift speed showed a westward increase to the Greenwich Meridian. Seasonal variations of the drift speed were high in autumn—early winter and low in spring, and their magnitudes also increased westward. Seasonal variations of the drift speed were significantly correlated with variations of sea levels at Syowa and Mawson Stations, and hence qualitatively consistent with geostrophic current variations. Thus, the scatterometer data are demonstrated to be useful in monitoring iceberg trajectory and oceanic current variations. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
57.
It is broadly acknowledged that the precision of satellite-altimeter-measured instantaneous sea surface heights (SSH) is lower in coastal regions than in open oceans, due partly to contamination of the radar return from the coastal sea-surface state and from land topography. This study investigates the behavior of ERS-2 and POSEIDON altimeter waveform data in coastal regions and estimates a boundary around Australia's coasts in which the altimeter range may be poorly estimated by on-satellite tracking software. Over one million 20 Hz ERS-2 (March to April 1999) and POSEIDON (January 1998 to January 1999) radar altimeter waveform data were used over an area extending 350 km offshore Australia. The DS759.2 (5'resolution) ocean depth model and the GSHHS (0.2 km resolution) shoreline model were used together to define the coastal regions. Using the 50% threshold retracking points as the estimates of expected tracking gate, we determined that the sea surface height is contaminated out to maximum distance of between about 8 km and 22 km from the Australian shoreline for ERS-2, depending partly on coastal topography. Using the standard deviation of the mean waveforms as an indication of the general variability of the altimeter returns in the Australian coastal region shows obvious coastal contamination out to about 4 km for both altimeters, and less obvious contamination out to about 8 km for POSEIDON and 10 km for ERS-2. Therefore, ERS-2 and POSEIDON satellite altimeter data should be treated with some caution for distances less than about 22 km from the Australian coast and probably ignored altogether for distances less than 4 km.  相似文献   
58.
利用卫星遥感技术监测赤潮的研究   总被引:8,自引:0,他引:8  
赤潮灾害的频繁发生,给海洋生态环境和海洋渔业经济造成了严重危害。卫星遥感技术的不断完善,为快速、有效地动态监测赤潮灾害提供了可能,通过卫星图片的校正、合成、分析、解释、判断分析,可以迅速连续地掌握赤潮的发生状况,对于研究防控和治理赤潮灾害有着十分重要的意义,本文就如何利用卫星遥感技术监测赤潮进行了探讨。  相似文献   
59.
高分辨率遥感技术在厦门海湾生态环境调查中的应用   总被引:5,自引:0,他引:5  
林桂兰  孙飒梅  曾良杰  庄世坚 《台湾海峡》2003,22(2):242-247,T003
对于局部区域研究,高分辨率卫星遥感及其影像的智能化处理技术是获取信息的新手段.本文以IKONOS遥感影像在厦门海湾的应用为例,探讨高分辨率遥感卫星影像应用于海湾生态环境调查与分析的应用技术.通过分析高分辨率影像地物特征,提出高分辨率遥感影像的重要处理技术:采用不同缩放尺度进行分类和利用空间特征及纹理结构进行专题信息提取。  相似文献   
60.
遥感与GIS支持下的海洋渔业空间分布研究——以东海为例   总被引:9,自引:1,他引:9  
基于海洋渔业多年来生产实践所表明的海洋渔场与海洋水文要素密切相关性,将研究区的遥感融合信息与生产数据进行GIS空间配准,同时建立了诸多要素数据的空间聚类模式,利用该模式提取了水文信息和中心渔场信息相关联的空间分布规律的隐伏信息,由此阐述了实现海洋渔业现代化,应用空间遥感融合信息和GIS支持下指导海洋渔业生产的渔情预报有着重要意义.  相似文献   
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