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1.
简要介绍了国内外近海岸悬浮泥沙定量化遥感反演的研究进展及悬浮泥沙遥感反演模型的建立方法,通过对国内外近年研究的部分悬浮泥沙遥感反演模型进行简单分类、对比分析得出其优缺点,并针对部分悬浮泥沙遥感反演模型的不足和目前遥感技术在悬浮泥沙定量反演中的应用提出了一些肤浅见解。  相似文献   

2.
在曹妃甸近海水体实测光谱数据分析的基础上,与同步采集的水体悬浮泥沙浓度进行相关分析,选用合适的TM数据的遥感变量参数,根据2008年实测的四个剖面29个站点的海洋水色数据建立了水体悬浮泥沙浓度与TM数据对应的遥感定量反演模型,并用18个独立样本点进行了精度评价.研究结果表明:曹妃甸近海水体光谱曲线基本呈现单峰现象,敏感...  相似文献   

3.
本文推导出来悬浮泥沙遥感定量的统一式,其形式包含了Gordon关系式和负指数关系式,其它各悬浮泥沙的关系式可看作是该统一式的近似。由多个例子的计算表明统一式的相关性和精度要高于目前国内外使用的悬浮泥沙定量的遥感模式。该统一式被成功地应用于珠江口伶仃洋的遥感定量分析中。  相似文献   

4.
遥感影像的大气校正是遥感定量化研究的难点之一。以曹妃甸近岸海域为研究区,以水体悬浮泥沙浓度(suspended sediment concentration,SSC)定量反演为目标,采用6S(second simulation of the satellite signal in the solar spectrum)模型和FLAASH模型对研究区MODIS影像的大气校正方法进行对比实验,对2个模型校正前后的影像质量以及对目标地物信息的校正效果进行了评价。研究结果表明:2种模型均能在一定程度上削弱大气对水体信息的影响;相比之下,6S模型校正后影像质量优于FLAASH模型,能更真实地反映目标地物,可更好地实现对近岸海域遥感影像的高精度大气校正;将6S模型大气校正后的MODIS影像应用于悬浮泥沙浓度的遥感反演,反演结果的平均相对误差为24.79%,均方根误差为4.32 mg/L。研究结果可为近岸海域Ⅱ类水体大气校正方法的选择提供依据,为深化泥沙运移规律研究及水质、水环境评价提供技术支持。  相似文献   

5.
悬浮泥沙是湖泊水体的重要水质要素之一,是湖泊水生态系统重要影响因子。利用遥感提取的鄱阳湖底质类型数据,对各类型底质区域上泥沙模型参数进行敏感性分析,基于2011年实测的不同底质区上泥沙浓度数据率定得到空间上不一致的泥沙模型参数,从而建立鄱阳湖丰水期二维悬浮泥沙输运模型。利用该模型模拟预测2013年丰水期悬浮泥沙输移过程,实测泥沙数据验证表明,模拟悬浮泥沙均方根误差为19.8 mg/L,相关系数R2为0.78,该模型能够较好地进行悬浮泥沙模拟预测。对比模型模拟和遥感反演的悬浮泥沙空间分布,两者具有较好的空间一致性,进一步表明该模型能够可靠地模拟预测鄱阳湖悬浮泥沙的时空动态变化。本研究充分利用遥感数据辅助建立鄱阳湖泥沙输移模型,为湖泊水环境动态变化监测提供有力的技术方法支撑,为进一步进行鄱阳湖水环境动态变化的数值模拟预测研究提供基础。  相似文献   

6.
李建  田礼乔  陈晓玲 《测绘学报》2017,46(4):478-486
对地观测技术的快速发展为水环境定量遥感监测提供了多源遥感数据的有利支撑,然而多源数据空间尺度差异引起的遥感数据和定量产品的不一致性严重制约了水环境科学研究和业务化应用。针对多源遥感数据的空间尺度转换和尺度误差问题,本文提出一种模拟遥感成像过程点扩散函数(PSF)的多源遥感数据空间尺度转换方法。以高空间分辨率GF-1卫星16m遥感数据为基础,模拟了常用的内陆水环境监测卫星Landsat TM/ETM+/OLI(30m)、Terra/Aqua MODIS(250m、500m、1000m)数据,系统研究了高动态浑浊水体(以鄱阳湖悬浮颗粒物监测为例)多源定量遥感监测的空间尺度误差,并对比分析了常用的多源数据尺度转换方法(基于遥感反射率数据平均法和基于悬浮颗粒物产品平均法)的有效性。结果表明,基于点扩散函数的空间尺度转换方法与传统方法具有较高的相关性,基于遥感反射率数据平均法的水环境定量遥感产品的误差水平低于基于悬浮颗粒物产品平均法;相对于南海等相对平稳水体的低空间尺度误差水平(0.5%),在高动态浑浊的内陆或近岸水环境遥感监测中,由空间尺度变化引起的产品误差可达±5%左右。因此,在高精度水环境定量遥感发展应用的需求和多源多尺度遥感数据协同的背景下,本文研究对于提高多源遥感监测产品的一致性和应用能力具有重要理论和现实意义。  相似文献   

7.
海洋测量学     
CH20051979基于遥感反演结果的悬浮泥沙时空动态规律研究———以珠江河口及邻近海域为例=Spatial andTemporal Dynamics of Suspended Sedi ment Concentrationinthe Pearl River Estuary Based on Remote Sensing/陈晓玲,袁中智(武汉大学),李毓湘,韦永康(香港理工大学)∥武汉大学学报(信息科学版).-2005,30(8).-677~681选择了珠江口及其邻近海域1995年~2000年152个时相的NOAA/AVHRR影像反演的悬浮泥沙浓度结果,通过对悬浮泥沙反演结果影像的叠加,求算叠加像素点像素平均值,计算了研究海域在1995~2000年间月、季及丰枯水期几个时…  相似文献   

8.
选择了珠江口及其邻近海域1995年~2000年152个时相的NOAA/AVHRR影像反演的悬浮泥沙浓度结果,通过对悬浮泥沙反演结果影像的叠加,求算叠加像素点像素平均值,计算了研究海域在1995~2000年间月、季及丰枯水期几个时间尺度上的悬浮泥沙平均浓度及其平均变化。结果大致表明了陆地径流对海域的影响范围和悬浮泥沙在海域的运动方向。  相似文献   

9.
神舟三号CMODIS数据获取长江口悬浮泥沙含量的时空分布   总被引:6,自引:2,他引:6  
韩震  金亚秋  恽才兴 《遥感学报》2006,10(3):381-386
悬浮泥沙含量的时空分布是分析河口海岸冲淤变化、估算河流入海物质通量、研究海洋沉积速率和海洋环境的重要参数.成像光谱仪技术包含了丰富的空间、辐射和光谱三重信息.用中国神舟三号上34个波段的中等分辨率成像光谱仪(CMODIS)数据,采用经验线性法对其辐射亮度值进行了反射率转换,结合长江口现场调查资料,对长江口悬浮泥沙含量时空分布进行了遥感定量反演,取得了很好的效果.  相似文献   

10.
大雾区域地面能见度、垂直总水汽含量、雾滴有效半径等因子是对大雾进行有效监测的重要参数。以MOD IS探测器的卫星遥感数据资料为主要数据源,定量反演了这些大雾参数。能见度参数反演结果和气象地面观测能见度信息数据的对比表明其效果良好。所得垂直总水汽含量、雾滴有效半径也与以前国内外相关多年研究的结果趋势一致。此方法在这里成功的应用,说明其在遥感大雾监测中的潜在应用价值。  相似文献   

11.
Total suspended sediment (TSS) data concentrations are retrieved from two sets of satellite ocean color data (the Moderate Resolution Imaging Spectroradiometer (MODIS) onboard Aqua and the Korean Geostationary Ocean Color Imager (GOCI)) using an existing regional model to characterize spatial and temporal variation of TSS in the Yellow and East China Seas. MODIS-derived TSS maps show that TSS concentrations are, in general, high along the Korean and Chinese coasts including the Bohai Sea and the Yangtz River estuary, and lower in the middle of the Yellow Sea and the southeastern area of the East China Sea. The monthly average of 10-year MODIS data reveals that TSS values are highest during winter (January to February) and lowest in summer (July to August). Short-term TSS concentrations retrieved from GOCI data showed the dominant influence of semi-diurnal tidal changes on sediment dynamics through temporal (hourly) and spatial distribution in coastal zones of the Yellow sea. The results presented here demonstrate that the satellite-derived TSS products can be utilized as an application tool for future studies on long- and short-term sediment dynamics of turbid coastal waters. In particular, GOCI observations provide unique important capabilities to characterize and quantify the water properties at high temporal (hourly) and spatial (0.5 km) resolutions in the turbid coastal waters of the Yellow Sea and its vicinities.  相似文献   

12.
以MODIS红外谱段数据为基准,对高光谱红外谱段数据进行辐射交叉定标试验,同时运用高光谱红外谱段数据对近海海表水温进行了评估试验.交叉定标数据选取2012年—2013年冬、夏两季各一幅代表性图像,MODIS与高光谱红外谱段数据成像时间均为同一天白天.实验结果表明,天宫一号高光谱红外谱段数据与MODIS数据具有极好的相关性,相关系数R大于0.95;在此基础上建立了基于MODIS 32波段的辐亮度线性回归校正方程,并用于海表温度反演、检测自然与人工扰动造成的海表温度异常.基于校正数据反演的中国南北典型冬、夏代表性季节的海表温度与常识较为一致.由此表明,基于MODIS交叉定标的天宫一号数据可用于实际的业务化定量评估;同时,由于空间分辨率较高,天宫一号高光谱红外谱段数据在海水精细空间动态变化检测上表现出极好的性能.  相似文献   

13.
近岸/内陆水环境遥感的空间尺度问题研究包括空间变异尺度及遥感监测空间尺度需求,以及多源多尺度遥感数据及定量产品的空间尺度误差两个方面。利用长时序高分一号16 m遥感数据集高时空分辨率的综合优势,采用空间半变异函数分析方法获取了中国近岸/内陆典型水环境要素(以悬浮颗粒物为例)的空间变异尺度。基于水环境要素空间变异的连续性和泰勒级数展开理论,定量化地描述了空间尺度误差解析函数。结果表明,近岸/内陆水体等高动态水体的空间变异尺度平均在150 m以下,而外海等相对稳定水体空间变异尺度在300 m以上。随着空间分辨率的降低,受到空间变异和水环境要素非线性定量反演模型的共同影响,悬浮颗粒物的空间尺度误差显著增大,亟需重点研究区域化的尺度误差校正方法。  相似文献   

14.
In this study, a theoretical model for studying the scaling effects on the two-band ratio of red to near-infrared band (TBRRN) is suggested. The model is used to explain the relationship between scaling error and local scale error; the results revealed that a special scale scaling procedure can be divided into a series smaller scale scaling procedures, and the total scaling error is the sum of the scaling error of these series’ smaller scale scaling procedure. Consequently, under the condition that the local scale is adequately fine, the total scale error at the target scale may be estimated accurately. In order to understand the mechanisms associated with scale in practical remote sensing, TBRRN data with 250 m and 1 km resolution is estimated from MODIS data at 645 and 859 nm, retrieved on September 1, 2009, in the Yellow River estuary, China. It is found that the TBRRN estimated from the 1 km resolution MODIS data is ~2.94 % smaller than as estimated from the 250 m MODIS data. The large scaling error distributes neither in the turbid waters, nor in the low suspended sediment regions, but instead in the high-low suspended sediment concentration transitional zone, which may be attributed to the spatial variable of suspended sediment in the transitional zone. This paper also points out that, owing to the importance of total scale error in achieving NASA’s mission in oceanic remote sensing, the way in which to conveniently and precisely estimate the total scale error of remote sensing parameters may potentially be an important topic in the field of oceanic remote sensing, both in present research and in the future.  相似文献   

15.
An effective methodology for Bohai Sea ice detection based on gray level co-occurrence matrix (GLCM) texture analysis is proposed using MODIS 250 m imagery. The method determines texture measures for sea ice extraction by analyzing the discrepancy of textural features between sea ice and sea water. Sea ice extent and outer edge are recognized accurately by texture segmentation owing to significant differences in texture statistical features between ice and water. The texture analysis method can properly eliminate perturbations on sea ice extraction due to suspended sediment. It effectively solves the problem of spectral confusion and sea ice misassignment in the conventional gray-threshold segmentation and ratio-threshold segmentation methods. The method eliminates the need for threshold range setting for sea ice segmentation. Taking the Bohai Sea as an example, the results of the proposed method are validated using co-temporal HJ1B-CCD 30 m imagery by visual interpretation, and the accuracy of the method are evaluated using confusion matrix. The results show that the proposed method is superior and more reliable for sea ice detection compared to conventional methods, providing an ideal tool for precise sea ice extraction.  相似文献   

16.
辐射沙脊群海域悬沙场遥感反演方法   总被引:1,自引:1,他引:0  
利用2006年江苏908调查水文泥沙测验数据和同期MODIS影像建立遥感定量反演模式,获取了半个潮周期的悬沙场以及全潮平均悬沙场,进行了辐射沙脊群海域悬沙场遥感反演方法的研究,并结合悬沙数学模型对结果进行了验证。研究表明,在辐射沙脊群海域,敏感参数(B1-B4)/(B1+B4)的对数模式反演悬沙场精度较高;遥感反演结果在总体上与数学模型计算结果相似,悬沙高值区主要分布在弶港、废黄河口和长江口附近;在细节上比数学模型表现得更精细,能清晰地反映河口、沙洲、水道等地貌对悬沙分布的影响。  相似文献   

17.
MODIS数据的海洋表面温度反演   总被引:4,自引:0,他引:4  
以黄海及东海海域为对象,研究用MODIS数据提取我国海域海洋表面温度的方法,建立了适合于我国海域的MODIS海洋表面温度遥感实用模式。研究表明,此算法的反演精度比较高,用这种模式计算的海面温度可较真实地反映海洋表面温度分布状况。由于同一天可以获取同一地区的上午和下午两景MODIS数据,因此MODIS数据在探测海洋现象方面具有独特的优势。  相似文献   

18.
The two main inherent optical properties (IOPs) namely absorption and back scattering coefficients were estimated using a quasi analytical algorithm (QAA) for open and coastal ocean waters of Arabian Sea. Absorption due to gelbstoff and back scattering due to the particulate matter were calculated using the quasi analytical algorithm for all the in-situ measured reflectance spectra collected in the Arabian Sea. A comparative study was made to study the spectral variability of reflectance spectra in open as well as coastal waters of Arabian Sea. Spectral analysis was made for the absorption and back scattering coefficients calculated using the QAA for both open and coastal waters. The absorption coefficient in the open ocean waters vary from a minimum value of 0.029 to a maximum value of 0.445 and it varies from a minimum value of 0.081 to a maximum value of 4.000 for the coastal waters of Arabian Sea. Absorption due to gelbstoff or the CDOM ag(λ), calculated for the Arabian Sea waters show a variation of 0.000202 to 0.112437 for open ocean waters and it varies from 0.002848 to 2.8936 for coastal waters of Arabian Sea. Particulate back scattering coefficient for open ocean waters vary from 0.0000307 to 0.006575 whereas bbp(λ) vary from 0.000167 to 0.026014 for coastal ocean waters. The minimum slope for the open ocean waters is 0.989 and maximum value of 2.147 (average value of 1.7) was observed; whereas a minimum value of 0.046 and a maximum value of 1.201 (average value of 0.6) were observed from the in-situ spectra for coastal waters of Veraval. The slope ‘Y’ estimated from the model is 1.957 for open ocean waters and 0.515 for coastal waters collected in the Arabian Sea.  相似文献   

19.
Remote sensing has been extensively used for water delineation and has played an important role in water quality evaluation and environmental management strategies. Suspended sediments are important determinants of water quality in coastal zones. Remote sensing enables the effective monitoring of total suspended sediments (TSS) and the detection of areas with critical water quality issues. This study aims to develop and implement regression models for estimating and mapping TSS concentrations from Advanced Land Observation Satellite (ALOS) images over the coastal waters of Langkawi Island, Malaysia. The algorithm was developed based on the water reflectance model, which is a function of the inherent optical properties of water. Such properties can then be linked to TSS concentration. In this study, an ALOS Advanced Visible and Near Infrared Radiometer type 2 device was used as the imaging sensor system. Concurrent complementary in-situ water samples were collected within the area coverage of the sensor, and digital numbers (DN) for each band corresponding to the sea-truth locations were determined. The extracted DN values were converted into reflectance values and then regressed with their respective sea-truth data. An algorithm was proposed to obtain the regression coefficient. This algorithm can estimate TSS concentrations with a high correlation coefficient (R2?=?0.96) and low root-mean-square error (RMSE?=?1.98 mg/l). Finally, a map of the TSS concentration was generated by using the proposed algorithm. This study found that TSS mapping can be conducted by using ALOS data over the coastal waters of Langkawi Island, Malaysia.  相似文献   

20.
There is considerable interest in accurately estimating water quality parameters in turbid (Case 2) and eutrophic waters such as the Western Basin of Lake Erie (WBLE). Lake Erie is a large, open freshwater body that supports diverse ecosystem, and over 12 million people in the mid-western part of the United States depend on it for drinking water, fisheries, navigational, and recreational purposes. The increasing utilization of the freshwater has deteriorated the water severely and currently the lake is experiencing recurring harmful algal blooms (HABs). Improving the water quality of Lake Erie requires the use of robust monitoring tools that help water quality managers understand sources and pathways of influxes that trigger HABs. Satellite-based remote sensing sensor such as the moderate resolution imaging spectroradiometer (MODIS) may provide frequent and synoptic view of the water quality indices. In this study, data set from field measurements was used to evaluate the performance of 14 existing ocean color algorithms. Results indicated that MODIS data consistently underestimated the chlorophyll a concentrations in the WBLE, with the largest source of errors from dissolved organic matter and xanthophyll accessory pigments in this data set. Most of the global algorithms, including OC4v4 and the Baltic model, generated near-identical statistical parameters with an average R2 of ~0.57 and RMSE ~2.9 μg/l. MODIS performed poorly (R2 ~0.18) when its NIR/red bands were used. A slightly improved model was developed using similar band ratio approach generating R2 of ~0.62 and RMSE ~1.8 μg/l.  相似文献   

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