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The influence of temperature variations on the determined concentrations of dissolved organic matter (DOM) in water was investigated by laser induced fluorescence (LIF) technique in laboratory. The effect of temperature on CDOM fluorescence was investigated in freshwaters of Xixi River and in aqueous standards. The total luminescence spectra (TLS) of CDOM in several types of water samples with laser-induced fluorescence (LIF) measurements using a 405 nm wavelength excitation source were measured in the laboratory. A temperature calibration equation was derived to standardize CDOM fluorescence measurements to a specific reference temperature. Laboratory experiments with a portable LIF LiDAR showed that CDOM fluorescence intensity decreased as ambient water temperature increased. High correlation (R2=0.91) was observed between concentration of CDOM and fluorescence normalized to water Raman scattering with the temperature calibration method. The results demonstrated that temperature calibration is a necessary and important aspect of CDOM monitoring using in situ fluorescence sensors.

In order to obtain the spectral information of objects and improve the retrieval of quantitative parameters from remotely sensing data accurately on land or over water bodies, atmospheric correction is a vital step, certainly, it is also a prerequisite to hyperspectral imagery data analysis approaches. On the base of previous studies, the atmospheric correction algorithms were divided to two categories: image-based empirical and model-based correction methods. The Quick Atmospheric Correction (QUAC) and Dark Object Subtraction (DOS) methods belong to the empirical or semiempirical methods, however, the Fast Line-of-sight Atmospheric Analysis of Spectral Hypercube (FLAASH) method was developed from the radiative transfer model. In this paper, we initially evaluated the performance from Hyperspectral Imager for the Coastal Ocean (HICO) of 16 Nov 2013 using QUAC, DOS, and MODTRAN integrated in FLAASH, and compared the results of these correction methods with in situ data. The results indicate that the method of FLAASH model performs much better than DOS and QUAC in atmospheric correction for HICO hyperspectral imagery, although the DOS and QUAC method is conducted more easily and do not require inputs of complex parameters.

A coordinated retrieval method for sea surface salinity based on SMOS and ocean color data was developed. The method retrieved sea surface salinity in open sea based on SMOS data, and those with much RFIs in the coastal area using ocean color data, aCDOM. Tight relationships between surface water salinity and in situ aCDOM were found during the cruises in the Yangtze River estuary on April 2013 and Hangzhou Bay in May 2014, distributions of aCDOM revealed gradual downward trends of magnitudes, as water flowed down the Yangtze River estuary into the ECS coast. A dilution process was detected as water flowed down the Yangtze River and into the ECS coast. Thus, a salinity inversion model from the negative relationship between salinity and aCDOM was developed firstly. Then we matched the SSS products with different spatial resolution retrieved based on SMOS and ocean color and combined them. In the end, we compared the SSS measurements between those based on only SMOS data and those based on method in this paper, and found that the method can make up the phenomenon of lack of data effectively.

It is very hard to access cloud-free remote sensing data, especially for the ocean color images. A cloud removal approach from ocean color satellite images based on numerical modeling is introduced. The approach removes cloud-contaminated portions and then reconstructs the missing data utilizing model simulated values. The basic idea is to create the relationship between cloud-free patches and cloud-contaminated patches under the assumption that both of them are influenced by the same marine hydrodynamic conditions. Firstly, we find cloud-free GOCI (the Geostationary Ocean Color Imager) retrieved suspended sediment concentrations (SSC) in the East China Sea before and after the time of cloudy images, which are set as initial field and validation data for numerical model, respectively. Secondly, a sediment transport model based on COHERENS, a coupled hydrodynamic-ecological ocean model for regional and shelf seas, is configured. The comparison between simulated results and validation images show that the sediment transport model can be used to simulate actual sediment distribution and transport in the East China Sea. Then, the simulated SSCs corresponding to the cloudy portions are used to remove the cloud and replace the missing values. Finally, the accuracy assessments of the results are carried out by visual and statistical analysis. The experimental results demonstrate that the proposed method can effectively remove cloud from GOCI images and reconstruct the missing data, which is a new way to enhance the effectiveness and availability of ocean color data, and is of great practical significance.

A dual-wavelength lidar fluorosensor system for fast diagnosis of chromophoric dissolved matter (CDOM) in water in the Pearl River estuary was discussed. The laser-induced fluorescence (LIF) system used two lasers as excitation sources with wavelength at 355nm and 532 nm, and a hyperspectral CCD spectrometer was used to record the fluorescence signal. The overlapping fluorescence spectra of water Raman scattering and CDOM were separated with fitting bi- Gaussian of the least squares method. High correlation was observed between concentration of CDOM and fluorescence normalized to water Raman scattering. The in situ results demonstrated rapid characterization of dissolved organic matter can be done by the LIF technique.

The distribution and transport of suspended sediment in the coastal areas has attracted more and more attention. Monitoring and modeling of the distribution and transport of suspended sediment is significant. The mutual promotion of remote sensing and numerical simulation plays an important role on the coastal water quality study. In this study, a method of coupling derived suspended sediment concentration (SSC) images with numerical model, based on GOCI and COHERENS (COupled Hydrodynamical-Ecological model for REgioNal and Shelf seas) model, is proposed to monitor the suspended sediment dynamics in the East China Sea. The retrieved SSC were extracted from GOCI images, to set as initial condition and employed to calibrate the parameters and validation for the hydrodynamic modeling and sediment transport modeling, respectively. The model is forced by considering tidal surface elevation at open sea boundary, river discharges, surface stress as a function of wind speed, air temperature, relative humidity and cloud coverage, bottom roughness and heat flux through sea surface. The model results are in accord with the in situ measurements. The results show that: (1) Numerical model which initialized with satellite-derived SSC data can quickly response to the changes of sediment concentration in real sense. (2) Remote sensing is helpful to calibrate and validate the model for simulating the suspended sediment concentration distribution. (3)The proposed approach can obtain reasonable simulated results in the East China Sea. (4) It is of great significance to combine remote sensing and numerical simulation together to study the water quality in the coastal areas.

In remote sensing image applications, the image matching is a very key technology, its quality directly related to the quality of the subsequent results. This paper studied an improved SIFT features matching method for muili-source remote-sensing image registration based on GPU computing, epipolar line and least squares, its main purpose is to take both accuracy and efficiency into consideration. This method is firstly based on tonal balanced methods matching, and then exracts SIFT features based on the GPU computing technology, and then matchs feature points based on epipolar line and least squares matching method with RANSAC method, finally analies error sources of SIFT mismatch, researchs an improved SIFT mismatch reduce strategy.The experimental results prove that the method can effectively improve the efficiency and precision of SIFT feature matching.

Red tide not only destroys marine fishery production and deteriorates the marine environment, it also causes human health problems. In China, the East China Sea has a high incidence of red tide disasters. Remote sensing technology has been proven an effective means of monitoring red tides. Spectral information of red tide water is an important basis for establishing red tide remote sensing monitoring models. This paper analyzes and compares the differences between red tide event spectral curves and multiyear monthly averaged spectral curves of MODIS data from July 2002 to June 2012, and develops a red tide monitoring algorithm based on the background field, to extract red tide information of the East China Sea. With the application of the algorithm in the East China Sea, it reveals that it can effectively determine the location of red tide and extract red tide information.

Chromophoric dissolved organic matter (CDOM) exists in all natural waters. Researches on optical properties of CDOM play an important role in ocean color remote sensing retrieval. The optical properties of CDOM in Zhejiang coastal waters were investigated from August 18, 2009 to June 9, 2011 covering four seasons. Based on the measured data, the distribution of the absorption coefficient of CDOM was analyzed. The results showed that absorption coefficient at 440 nm (a(440)) decreased with the offshore direction, and the relatively high value of a(440) was observed generally in the coastal waters and low value in the adjacent waters. The distribution reflected the terrigenous origin characteristics of CDOM. The relationship between salinity and a(440) of the four seasons was discussed. The results demonstrated that a(440) had a significant negative linear relationship with the salinity. That is to say, CDOM took on the conservative behavior in the research region.

Aerosol optical thickness (AOT) and atmospheric visibility are two important weather parameters. AOT reflects the state of the atmosphere,-and atmospheric visibility is widely used in various aspects of social life. Generally, it is reported in literatures that both of them are affected by Air Pollutants and other meteorological factors, such as surface pressure, ground temperature, wind speed, precipitation. In this paper, a statistic relationship expression is established between AOT and atmospheric visibility on the basis of the point-to-point meteorological observations. In the national region, the correlation between atmospheric visibility and weather factors indicates that the surface pressure has great influence on atmospheric visibility all the year round. And the influence based on precipitation is more obvious in spring and summer, mean-while wind speed and temperature play important roles in autumn and winter. A significant positive correlation was found between AOT and API. To express the relationship between atmospheric visibility and AOT, some computable models were utilized. According to the accuracy analysis, the cubic curve model and the power function model are more accurate. And both RMSE (root-mean-square error) of them is higher than 0.47. But the coefficient of cubic curve is more complex in practice. Finally, a simple estimation model of aerosol optical thickness based on meteorological station observed atmospheric visibility was conducted using power function. The Pearson coefficient between calculation of power function and observation is 0.73.

HJ-1A/B were two small satellite constellations, that were launched for the environment and disaster monitoring and forecasting on September 6th, 2008. Based on the advantages of high temporal and spacial resolution of the HJ CCD data, this paper aims at evaluate four inversion algorithms of suspended sediments concentration by the remote sensing reflectance in the Hangzhou Bay. First, the atmospheric correction of HJ-1 A/B CCD imagery was carried out using fast line-of-sight atmospheric analysis of spectral hypercubes (FLAASH) model, in which aerosol optical depth was retrieved from synchronous Terra/MODIS data. Then, four classical band ratio algorithms were evaluated. Results show that He’s GOCI model was better than others with 12.75% relative error. At last, we compare the discrepancy between He’s GOCI algorithm and any other three model, results indicate that the other three empirical algorithms performance not very good because of the difference come from different satellite data, various study area, different research season, distinct correction result. This research has an important practical significance to improving the SSC inversion in the HZB.

The variations of Dissolved Oxygen (DO) in the near-bottom waters off the Changjiang (Yangtze River) Estuary before and after the passage of typhoons are investigated using both remotely sensed and in situ data sets. The Ekman pumping velocity during and after Typhoon was calculated. From buoys observation, typhoon passed by cause the water exchange between upper and lower layer. The mixture made the Dissolved Oxygen (DO) level changed to high level in short time. The level of DO at 50 m increased from 3.2 to 6.2 during the period of strong winds (< 30 knots) of Typhoon Muifa. The mixing process occurred in a short time, about 1-2 hours. The raise and resume result also has been verified from cruise observations. Typhoon effects hypoxia in many aspects. Typhoon can affect hypoxia in many ways. SST decreases as typhoon passes directly over the water. The concentrations of surface Chl a increase gradually due to mixing triggered by the typhoon. The affected area and time of change of hypoxia depend on the wind speed and the movement of the typhoon as well as the water depth.

Red tide not only destroys marine fishery production, deteriorates the marine environment, affects coastal tourist industry, but also causes human poison, even death by eating toxic seafood contaminated by red tide organisms. Remote sensing technology has the characteristics of large-scale, synchronized, rapid monitoring, so it is one of the most important and most effective means of red tide monitoring. This paper selects the high frequency red tides areas of the East China Sea as study area, MODIS/Aqua L2 data as the data source, analysis and compares the spectral differences in the red tide water bodies and non-red tide water bodies of many historical events. Based on the spectral differences, this paper develops the algorithm of Rrs555/Rrs488> 1.5 to extract the red tide information. Apply the algorithm on red tide event happened in the East China Sea on May 28, 2009 to extract the information of red tide, and found that the method can determine effectively the location of the occurrence of red tide; there is a good corresponding relationship between red tide extraction result and chlorophyll a concentration extracted by remote sensing, shows that these algorithm can determine effectively the location and extract the red tide information.

Synthetic aperture radar (SAR) can measure directional wave spectrum based on the closed nonlinear SAR-ocean mapping mechanism. The according wave spectrum retrieval algorithm has been developing for decades, but some limitations remain, like high wave number cut off in azimuthal direction and the need for the first guess spectrum. Wave spectrometer is a kind of new satellite-based real aperture radar (RAR) operating at low incidence, which has a narrow beam and scans complete 360° by antenna rotation. It derives wave spectrum by the simple linear relation between the wave spectrum and the modulation spectrum from the wave spectrometer. The linear coefficient can be estimated by the nadir beam or external wind speed information. This paper proposes a method on the wave spectrum estimation based on the joint measurement from synchronous SAR and wave spectrometer. Firstly, the modulation spectrum is derived from the signal spectrum of the wave spectrometer, from which the relative wave spectrum can be constructed. Then the relative wave spectrum is seen as the first guess spectrum for the wave spectrum retrieval of SAR image. Because the relative wave spectrum has the same pattern with the real wave spectrum but has different absolute energy, we can retrieve the directional wave spectrum by the iteration way based on the relative wave spectrum from the SAR image. This paper makes use of simulation technology to validate the joint measurement. The simulation compares the input spectrum and the retrieved one in terms of peak direction, peak wavelength and significant wave height, which has a deviation of 6°, 4m and 0.3m, respectively. Simulation results show the joint measurement has the feasibility for the retrieval of directional ocean wave spectrum.

Asian dust often occurring in the spring can be transported to the China Sea, even far to the North Pacific region. In this process, the dust deposition brings some nutrients and microelements into ocean and can affect the marine ecosystem significantly, such as the phytoplankton populations. In this study, we firstly analyze the monthly variations of chlorophyll a (Chla) concentrations and aerosol optical thickness (AOT), and then consider three major dust storm events during April 2006 to study their impact on the chlorophyll concentrations along the track of the dust storm using satellite observations over the Yellow Sea, including AOT and the Chla from Modis, composited sea surface temperature (SST) from TRMM / TMI and AMSR-E, and sea surface winds (SSW) from Quikscat. The central of North Yellow Sea (38- 39°N,123-124°E) and South Yellow Sea (35-37°N, 123-125°E) are regions where Chla blooming frequently during dust events. The Chla usually up to 5-12mg/m 3 and the max value even greater than 30 mg/m 3 . Without high wind speed and suitable temperature, dust deposition could also cause chlorophyll concentrations increased, but its impact region is limited and intensity is small in the Yellow Sea. Due to the AOT usually overflow or failure over dust regions, the high AOT can denote dust event. In the future, the dust aerosol optical thickness and other properties need to be estimated for further study on the ocean biogeochemical response to Asian dust events.

The development of algorithm for the detection and monitoring of red tides, using data from Medium Resolution Imaging Spectrometer (MERIS), is discussed. The interpretation of in-situ measured remote-sensing reflectance spectra above both waters is presented in this paper. And a radiative transfer model based on Matrix Operator techniques is used to study feature of the reflectance peak near 700nm. Based on the analysis of measured and modeled spectrums, the redshift phenomenon is obviously observed above the red tide water. The reflectance peak is observed to shift progressively from a centre wavelength of 683nm (clear and green water) to longer wavelengths (red tide waters). By using MERIS fluorescence bands, the line height at 681 nm (LH681) and 709 nm (LH709) above a baseline through the measurements at 665 nm and 753 nm are calculated. It is found that due to the red-shift phenomenon the LH709 is much higher than LH681 in red tide waters. So in this paper, the ratio of LH709 to LH681 is used as an index to detect the red tides. The results of operational red tide detection in the East China Sea have been presented.

Concentration of suspended sediment directly affects the optical properties such as transparency and water color, and aquatic environment as well. The paper selects the Minjiang Estuary, southeast coast of China as study area, and has established inversion mode of suspended sediment by coupling field data with water-leaving radiation from MODIS data in Minjiang Estuary. Monthly-averaged concentrations and seasonal changes of suspended sediment from 2002 to 2009 were calculated and analyzed by the mode. The main results are as follows: (1) Normalized water-leaving radiance ratio(nLw 667 /nLw 488 ) from MODIS data has high relativity with the field observed turbidity by regression equation of Y = 0.618X2 -5.720X + 18.94 , in which Y is turbidity, X is nLW 667 / nLW 488 and R 2 is 0.716. (2)Suspended sediment in the Minjiang Estuary has obviously spatial and temporal distribution characteristics, that higher concentration of suspended sediment is in coastal water and decreases from shore to sea, and highest concentration happens in winter.

SWIM is a satellite-based Ku-band real aperture radar designed for measuring the directional ocean wave spectrum. This radar works at six incidence angles (from 0 degree to 10 degree) with the 360 degree azimuth scanning. The measurement principal has been proposed by Jackson and the simulation technology has been developed by Hauser, which depends on the comparisons between estimated modulation spectrum and reference one. Based on the method after the slightly modification, we consider the SWIM performance for measuring wave properties in cases of no noise, noise and noise with correction. Moreover, we propose the four methods to calculate the coefficient α(θ) , which include integration method, derivative method, wind speed experience method and significant wave height method. We substitute the α(θ) into the simulation, in which the forward simulation only use the integration method and the afterward simulation use the four method alternatively. From the results, it shows that the SWIM has the capacity of measuring the wave spectrum but it requires the proper processing for the elimination and correction of noise. Among the four methods, the wind speed experience method has a big deviation with reference spectrum, the integration and derivative methods have good results of measurements and the significant wave height method has moderate error and shows good in low wind speed.

Using the coupled ocean and atmosphere radiative transfer code (COART), the downward radiance distributions above the sea surface and at 1 m depth in the water are calculated. Combined with the discrete angle numerical model, the investigation of effect of instrument tilts on E d , E s and L u is provided. It is found that the average of the time series E s data will be to eliminate the effect of the tilt of surface incident irradiance instrument caused by the rocked boat. And different high tilt thresholds should be set respectively for E d and L u to flag invalid data records.

Digital change detection (CD) is the computerized process of identifying changes in the state of an object, or other earthsurface features, between different dates. During the last years, a large number of change detection methods have been proposed for change detection of multiple-temporal remote sensing images. Among these, change vector analysis (CVA) is a very important and widely used method. The key of CVA is to determine change detection threshold. Change detection threshold is a very valuable key for change detection precision. In the literature, many techniques to determine change detection threshold have been proposed. However, most of them are not robust and operational since images are diverse and complex, especially to very high resolution (VHR) data (e.g. images acquired by QuickBird, IKONOS, SPOT5 and WorldView satellites). Such discrimination is usually performed by using empirical strategies or manual trial-and-error procedures, which affect both the accuracy and the reliability of the change-detection process. In this paper, we analyze the algorithm based on minimal classifying error, the algorithm based on OTSU and the algorithm based on EM. To eliminate the complexity of VHR data, an improved algorithm based on EM is proposed. Suppose the difference image meets the Mixed Gaussian distribution model. First, the grey histogram of the difference image is fitted to the Mixed Gaussian Distribution Model (MGM). Then the change detection threshold is determined by the MGM graph combing the Bayesian Criterion and the actual situation. In experiment, the semi-automatic method is effective and operational.

Based on satellite remote sensing to study the effects of ocean color and Sea Surface Temperature (SST) is the leading method at present. From 2000 to 2008, there were about 70 times storms or typhoons passed over the South China Sea Area (108-120°E, 14-24°N). In this article, authors used SeaWiFS, MODIS and serials of NOAA satellite data to statistic analysis the effects of chlorophyll-a (Chl-a) and SST in the study area caused by tropic storms and typhoons near last decade and found: firstly, the Ekman Pumping Velocity (EPV) was up-to 1.4x10-3 m s-1 by typhoon CHAUCHU in 2006, and was more ten times than that without typhoon. It pumped the nutrients to the euphotic zone and improved the increment of Chl-a concentration with the rate of 58.33%. and this typhoon caused the maximum decrease of SST was up to 7°C. At the same time, the average increment of Chl-a in the whole study area was about 21.13% but the decrease rate of SST was 6.36% by 16 typhoons. From the results of statistic analysis we found out that the isopycnal displacement of the seasonal thermocline explains 53% and the weight of the typhoon explains 55% of the variance of Chl-a by typhoons; In addition, the maximum amplitude of the increment of Chl-a in the study area was near to the east of Vietnam, it was up to 53%. But near the pear river estuary area with high Suspended Sand Concentration (SSC) the chl-a density decreased after typhoon and the descent rate of Chl-a was about 35%.

The procedure of radiometric normalization is necessary as change detection (CD) is highly dependent on accurate geometric and radiometric correction. The quality of radiometric normalization highly affects the results of change detection. During the last years, many methods on radiometric normalization have been proposed. However, they are generally proposed not for CD. In this paper, we will discuss these methods for CD. The ultimate objective of CD is identifying changes in the state of an object, or other earth-surface features, between different data. If you can't properly deal with radiometric normalization in CD, or the relationship between radiometric normalization and CD, you will fall into trouble. With respect to the accuracy, efficiency and operation of radiometric normalization for CD in VHR(very high resolution images such as spot5,QuickBird,Iknos), we design the processing procedure of radiometric normalization for CD in multitemporal images. Moreover, an improved matching algorithm based on Harris corner detection is described in this paper, which makes full use of graphic point feature, gray-level pixel and location information. In experiment, the proposed procedure has been proved effective and can be recommended for use in CD projects.

Some missions have been carried out to measure wave directional spectrum based on airborne real aperture radar in a low incidence. For this study, the authors simulate the satellite-based real aperture radar image spectrum to validate the radar performance of measuring the directional wave spectrum based on the same principal as airborne one. In the processes of the simulation, the authors don’t take into account the rotation of antenna and the disturbing of the noise in order that the simulation can exclude other factors to purely verify the measuring theory feasibility in essence. The authors use Wen’s spectrum as the input spectrum of the simulation, which is a kind of wind-generated wave spectrum that can better describe the state of developi ng wave and the statuses of the Chinese sea fields. Following that, the simulated sea surface, backscatte red radar signal, modulation spectrum and the one dimension wave spectrum (two dimension one can be obtained by synthesizing every directional one dimension spectrum) are obtained, which is compared with the input spectrum. To have a comprehensive realization to the performance of the radar, different cases including different developing degree, wind speed and angle between dominant waves propagation direction and radar look direction are considered. Presen ted results show that Satellite-based real aperture radar can mostly measure the wave spectrum, but the capacity is limited on the cases of low wind speed, developing waves and the big angles. Keywords: Satellite-based real aperture radar, Wen’s wave spectrum, wave directional spectrum

Coastal islands are located in transitional environments where land and sea interact. It is main frontier to develop oceanic economy and to utilize oceanic resources. Insular environment is isolated and its ecosystem is also vulnerable. The exploitation and development of islands make result on its land-cover and land-use transition and the trace of the landcover change indicates the impact on it conversely. Many changes have taken place in coastal area of East China within past four decades, especially in rapidly developing large islands. For monitoring environmental changes in such area, this paper, taking Zhoushan Island and its surrounding islands as an example, explored the temporal composition and spatial configuration of the land-cover trajectories. The recent land-cover data derived from both SPOT5 imageries and the last land-use data which came from investigation department. The historical distribution in 1980 was obtained from visual interpretation of CORONA photograph. Then the land-cover changed map could be derived through previous and last land-cover map. And the following time-series of land-cover was acquired from the supervised classification results of TM/ETM imageries which ranged from 1986 to 2000. The classification result was improved by limitation the sample selection in unchanged area in land-cover changed map in classification procedure. All these used satellite imageries were registered to the SPOT5 panchromatic imagery which was rectified using DGPS data in advance. Therefore, the temporal-spatial distributions of land-cover have been examined, reconstructed and analyzed with the support of GIS software. Based on those work, we revealed that the land-cover had changed rapidly in Zhoushan Island.

Based on the in-situ data and ocean color remote sensing data of SeaWiFS, we found there was a black water region with the normalized water-leaving radiances less than 0.5 mW/(cm 2 •μm•sr) at the visible light wavelength. Yangtze River Estuary locates in the East China Sea shelf with shallow water. Affected by the tide mixing and the runoff of the Yangtze River and Qiantang River, the turbidity is very high. Generally, the water-leaving radiance is high in the turbid water because of the large particle scattering. The reason of the occurrence of this black water was analyzed by the inherent optical properties and the ocean color components. The results showed that black water was caused by the relative low values of the suspended particle matter concentration and the back scattering ratio.

Suspended sediment is an important parameter of water quality and a main factor to affect the lifetime of port use, which needs to be monitored on the spatial distribution and temporal changes. It also dominates the optical properties in the coastal ocean and makes it difficult to retrieve chlorophyll concentration and other water constituents from satellite remote sensing data. Many algorithms were developed to retrieve suspended sediment concentration (SSC) from satellite remote sensing data and most of them were tested to be used for the region of the East China Sea. The results show that relative errors are too large to be more than 100% under high concentration of sediments. This region, especially in the Yangtze estuary and Hangzhou Bay, is famous for large area distribution of high concentration of suspended sediment, as high as more than 1000 mg/l. A new algorithm is developed, based on a large amount of in-situ measurements of four big cruises, each of these cruises employ two big ships to take about two months to measure about 200 stations. First, the relationship between the water-leaving radiance at different wavelengths and SSC was analyzed and the results show that the radiance at green bands is sensible to SSC at low concentration and almost saturated at high concentration, while the radiance at red bands has a good relationship with SSC at high concentration, meanwhile the radiance at near-infrared bands has also a big value under high SSC. Then the accuracy of the algorithm is evaluated and shows that the algorithm has a nice performance both at low and high SSC. Finally, the algorithm is used to obtain SSC from SeaWiFS and MODIS data and the distribution of SSC show that the algorithm is suitable for retrieving SSC from satellite remote sensing data in the East China Sea.

The spectral diffuse attenuation coefficients of downward irradiance (Kd) and upward radiance (Ku) are calculated from a profiler spectrometer measured data. Both Kd and Ku are the parameters of apparent optical properties (AOP) and need to be normalized according to the position of the Sun and sky conditions. Three kinds of sky indices are used to indicate the atmospheric conditions of clear, overcast and partly cloudy at the time of measurements. The values of normalized Kd can be compared with the sums of total absorption and backscattering coefficients. The total values from both measured data and the models fit the normalized Kd with the correlation coefficients of 0.85 and 0.81, respectively. The accuracy of Kd is also evaluated by the spectral root mean square error (RMSE) less than 0.15 m -1 in the spectral range from 450 to 700 nm.

Beijing-1 small satellite has three bands of green, red and near-infrared, with spatial resolution of 32 meters. Three days Beijing-1 data are used to retrieve distribution and living status of Enteromorpha clathrata (a kind of green algae and called Hutai in Chinese). First, use the non-supervised classification to separate the kinds who has big spectral differences. Second, the cloud and cloud-covered green algae can be separated by the ratio of near-infrared and red. In the end, the green algae distribution is obtained. The NDVI is used for indicator of living status and density. MODIS has the advantage of high temporal although its spatial resolution is much coarse than Beijing-1. A decision tree is developed to retrieve green algae. First, the cloud is eliminated by its high reflectance. Second, the NDVI is calculated and a threshold value is set to determine whether the grid is green algae. The green algae distribution results from Beijing-1 and MODIS are compared. Generally, the Beijing-1 extracted green algae is coincide with the MODIS extracted green algae. The Beijing-1 extracted algae area is smaller than that of MODIS, because the MODIS has spatial resolution of 250-meter, its situation of mix pixel is severer.

Coral reefs are complex marine ecosystems that are constructed and maintained by biological communities that thrive in tropical oceans. The Dong-Sha Atoll is located at the northern continental margin of the South China Sea. It has being abused by destructive activity of human being and natural event during recent decades. Remote sensing offers a powerful tool for studying coral reef geomorphology and is the most cost-effective approach for large-scale reef survey. In this paper, the high-resolution Quickbird2 imageries which covered the full atoll are used to categorize the current distribution of coral reefs geomorphological structure therein with the auxiliary SPOT5 and ASTER imageries. Spectral and texture analysis are used to distinguish the geomorphological diversity during data processing. The Gray Level Co-occurrence Matrices is adopted for texture feature extraction and atoll geomorphology mapping in the high-resolution pan-color image of Quickbird2. Quickbird2 is considered as the most appropriate image source for coral reefs studies. In the Dong-Sha Atoll, various dynamical geomorphologic units are developed according to wave energy zones. There the reef frame types are classified to 3 different types according as its diversity at the image. The radial structure system is the most characteristic and from high resolution imagery we can distinguish the discrepancy between them.

Qinshan Nuclear Power Station is located in the Haiyan County of Zhejiang Province in east China. The warm water from their cooling systems is discharged into the Hangzhou Bay directly which will affect the ecosystem of coastal area in the bay. To study the influence of warming effect from the thermal discharge of the Qinshan Nuclear Power Station Phase2 and Phase3, the remote sensing image of the marine airborne multi-spectrum scanner (MAMS), the numerical modeling based COHERENS (A coupled Hydrodynamical Ecological Model for Regional Shelf seas) and shipboard water column measurements are all applied to explore the spatial and temporal distribution of the warm water. In order to get accurate boundary conditions, a larger area was simulated firstly to provide hydrodynamic parameter for the modeling area in the numerical simulation. From the remote sensing image, the numerical simulation and field observations, we can conclude that the thermal effluent from the Qinshan Phase2 and Phase3 cooling systems just influences coastal water on a small scale.

At the beginning of 2008, the south area of China suffered a rare heavy snow and low temperature weather, which brought enormous economic lose and broke the environment. The abnormal weather also influenced the ocean color environment. Through analysis of MODIS remote sensing 3A data during 2 months before and after the snowstorm and low temperature weather, the author finds that, on the one hand,compared with same period of last year, the sea surface temperature (SST) from the East China Sea to the South China Sea (18°N-32°N 108°E-126°E descended 2.57°C; the average chlorophyll-a concentration(CHL-a)rose from 1.198 mg. m -3 to 1.75 mg. m -3 in the snowstorm and low temperature weather period from January 11 to 31 of 2008 which was 1.46 times more than that of the same period of last year. On the other hand, compared with the period before snowstorm,the SST decreased from 22.42°C to 18.34°C but the CHL-a rose from 1.32 mg. m -3 to 1.60 mg. m -3 after the snowstorm. In addition,the sea water transparency(SDD) had a certain increase in the open sea of South China Sea, but the suspended sediment concentration(SSC) increased significantly near the seashore, the Yangtse River Estuary and the Pearl River Estuary, which increased 200% compared with the period before the snowstorm 2008. Through researching and indicating, the main reason of increase of the CHL-a in the near seashore area(the I water) was more probably due to the increase of the SSC, and the CHL-a by remote sensing has greater error, which rising from the high SSC led to the increase of CHL-a; but in the open sea the increase of CHL-a is that the SDD improved and then the euphotic increased. As a result,this could promote the growth of primary productivity. Therefore, it faces the better applied foreground to monitor the influence on the ocean ecosystem environment caused by the snowstorm and low temperature weather through remote sensing.

A complete data set is crucial for many applications of satellite images. Therefore, this paper tries to reconstruct the missing data sets by combining Empirical Orthogonal Functions(EOF) decomposition with Kriging methods. The EOF-based method is an effective way of reconstructing missing data for large gappiness and can maintain the macro-scale and middle-scale information of oceanographic variables. As for sparse data area (area without data or with little data all the time), EOF-based method breaks down, while Kriging interpolation turns effective. Here are the main procedures of EOF-Kriging(EOF-K) method: firstly, the data sets are processed by the EOF decomposition and the spatial EOFs and temporal EOFs are obtained; then the temporal EOFs are analyzed with Singular Spectrum Analysis(SSA); thirdly, the sparse data area is interpolated in the spatial EOFs by using Kriging interpolation; lastly, the missing data is reconstructed by using the modified spatial-temporal EOFs. Furthermore, the EOF-K method has been applied to a large data set, i.e. 151 daily Sea Surface Temperature satellite images of the East China Sea and its adjacent areas. After reconstruction with EOF-K, comparing with original data sets, the root mean square error (RMSE) of cross-validation is 0.58 °C, and comparing with in-situ Argo data, the RMSE is 0.68 °C. Thus, it has been proved that EOF-K reconstruction method is robust for reconstructing satellite missing data.

Hangzhou Bay in China is an important conveyor transporting contaminants from surrounding cities in Yangtze Delta. A numerical hydrodynamic model based on COHERENS (Coupled Hydrodynamical Ecological model for Regional Shelf seas) has been employed to simulate the pollutant transport trajectory and to obtain the retention ratio in the Bay. The forcing of the model include tides and freshwater. The influence of wind was explored by imposing the QSCAT/NCEP Blend Wind data into the numerical simulation. The bay was divided into 8 subdomains (S1-S8) and the simulation was performed in two months: March (the dry season) and July (the wet season). Two sets of numerical experiment were carried out with or without wind. Results indicated that wind plays a more important role on pollutant transport in the wet season than in the dry season. The influences of wind on the pollutant transport in 8 subdomians are different, especially in wet season. The retention ratio of S1 is most significantly affected by wind compared with other subdomains.

The Colored Dissolved Organic Materials (CDOM) and the de-pigmented particles are the main components affecting the ocean colors in China coastal waters (which are commonly considered as the Case II waters). Understanding of their spectral characteristics is very important to develop the regional bio-optical algorithms for ocean color remote sensing. The coastal water in East China Sea (ECS) is influenced by the terrestrial materials especially the Yangtze River outflow, which has high dissolved organic and suspended materials concentration and complex particles composition. In this paper, we analyze the in situ datasets collected in four seasons between 2006 and 2007 in ECS, and get the spectral absorption models of CDOM and de-pigmented particles. The distributions of absorption coefficients of CDOM ( ) and de-pigmented particles ( ) show a decreasing trend from coastal water to the off-shore waters, which is influenced mainly by the Yangtze River outflow and coastal currents with remarkable seasonal variation in ESC. The maxima of a dp CDOM a dp a dp is very high and even up to 90 m-1 level in estuary waters that it will apparently influence the retrieval of CDOM. The frequency of slops of the exponential spectrum of de-pigmented particles obeys the Gaussian distribution and it has good relationships with the absorption coefficient especially in the near-shore areas. The optical characteristics in ECS will give feasible reference to the further development of regional bio-optical algorithms.

The ocean color satellite sensors measure the water-leaving radiance from ocean, which is used to deduce the global chlorophyll-a concentration distribution and other information. The water-leaving radiance is mainly caused by the backscatter of particles in the water. Spectral backscattering coefficients of particles play an important role in determining the remote sensing reflectance and a model is developed to study the spectral characteristics of the particle backscattering coefficients. The backscattering model of particles is established based on the measured data at two wavelengths of 470nm and 700nm and the backscattering coefficients of phytoplankton are also deduced from the total particles. The parameter n in the model is deduced from chlorophyll-a instead of using a constant value and the backscattering coefficient of particles at 700nm is retrieved from chlorophyll-a using a power function. To deduce the backscattering model of phytoplankton, the ratio of phytoplankton absorption to the total absorption of particles is used to separate the phytoplankton part from total backscattering values. The backscattering model of phytoplankton is established with a high correlation coefficient of 0.80 and the parameter values of the model are very close to those of Sathyendranath. The range of phytoplankton backscattering coefficients is from 0.0018 to 0.016m-1, almost half of that scattered by total particles. The backscattering properties of phytoplankton also agree with the normalized diffuse attenuation coefficients of seawater, which can be used in the bio-optical models in the coastal ocean. © (2008) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The multiscale analysis method is considered as an effective way to study the remotely sensed imageries of such complex landscape system. In order to overcome the shortcoming in applications of multiresolution segmentation, a four-step approach has been brought forward for homogeneous image-object detection. This is helpful to determinate the various optimal scales for diverse ground-objects in image segmentation and the potential meaningful image-objects fitting the intrinsic scale of the dominant landscape objects. Coastal landscape is complex system composed of a large number of heterogeneous components and some of them exhibit in homogenous areas. Satisfactory results were obtained in its applications in high-resolution remote sensing imageries on anthropo-directed area. The IODA result of man-made ground object is better than nature landscape because most man-made grounds objects have evident border. If the resolution of remotely sensed imagery is high enough to display object frontier then the image-objects detection results reveal perfect in MDF object candidates.

Data fusion is always a hot field in remote sensing research. It mainly includes checking, correlating, integrating and estimating multiple kinds of Data. Integration of global remote sensing image and local vector data is often necessary. In this paper, for global east Chinese high resolution remote sensing coast zone image and local vector data about ocean planning, we will introduce one way based on ArcGIS, in which the two kinds of data would be rapidly integrated. First, we change the vector data into raster data, then adjust these raster data precisely by Georeferencing module of ArcGIS, then vector and integrate data which we needed by Arcscan module of ArcGIS, at last, we program custom codes to solve the conflict between integrated new data and old data in VBA of ArcGIS. In the process, we wish to improve efficiency through a good management of map raster data.

Diffuse attenuation coefficient is an apparent optical property (AOP) which directly links to the inherent optical properties in ocean color remote sensing. So far, the study on the satellite retrieve algorithm of water diffuse attenuation coefficient has not been deeply-going, which is mainly discussed using the bands-ratio methods based on the in situ data. Only a few scientists apply the remote sensing data (such as SeaWiFS and MODIS) to retrieve the diffuse attenuation coefficient based on the model developed by Mueller (2002). In this paper, a quasi-analytical algorithm of spectral diffuse attenuation coefficients were developed based on the QAA algorithm of the inherent optical properties (IOPs) developed by Lee (2002). The model could retrieve multi-bands of the diffuse attenuation coefficients at 412 nm, 443 nm, 490 nm, 510 nm and 555nm wavelength. The in-situ optical dataset of South China Sea in 1999 was used to validate the model, and the results showed that the model had a good performance in the case I water in South China Sea, and the relative errors were 15.4%, 12.6%, 13.3%, 10.2%, 11.9%, 9.8% and 10.3% for the 412 nm, 443 nm, 490 nm, 510 nm, 520 nm, 555nm and 565 nm bands respectively. For the complex case II water, the model should be further localized and tested.

Multi-temporal series of satellite SPOT-VEGETATION Normalized Difference Vegetation Index (NDVI) has long time-series from 1998 to present. The convenient downloading policy make those data can be widely used all through the world. The data is used for global vegetation monitoring and variation analysis. The spring onset date reflects the vegetation growth and its feedback to climate and human activity, and become an important variable for the global climatic change and production monitoring. In this paper, the spatial spring onset date information in south and central China is portrayed, and the spring onset frequency distribution map is sketched by using the multi-year 10-days composite SPOT/VGT NDVI data. First, the long time series NDVI is reconstructed. Then a relative threshold value method is given to determine whether the vegetation begins to resuscitate. The spring onset frequency map mainly parallels the latitude. But because of the heterogeneity of vegetation and monsoon, the spring onset movements do not parallel the latitude completely.

Because of global climatic variations and anthropogenic influence on local environment, as the active interaction belt between ocean and land, the coastal ecosystems are sensitive even part of them are under pressure. It is of very necessary to diagnose whether they are in healthy stage. The Zhejiang coastal zone situated at about 120°E-123°E and 27°N-31°N, the landuse have changed largely during the past 20 years as long as the rapid economic development. In this paper the largest island-Zhoushan island- in the Zhejiang coastal line is selected as the study site. The objective is to establish a way to assess coastal ecosystem health stage. Indicators include the landuse transformation, water quality, ecosystem services during 1986 to 2005. The results indicate that the human pressure become more and more large. The scene generally is the outcome of economic pursuing activity. In the discussion we also provide some strategy to keep the human and nature harmonious.

Studies on the spectral reflectance of canopy and leaves of various cottons were performed. Spectral reflectance of six variety cotton over the 350-2500 nm range with a spectral resolution of 3 nm were obtained this study. In the early growth the spectral reflectance of cotton canopy increased with time, but in the later growth the spectral reflectance of cotton canopy decreased with time. In the main stem of cotton, the spectral reflectance of leaf decreased with leaf position up. The spectral reflectance of leaf increased with addition of leaves. The curve of spectral reflectance was up with water losing of leaf. In the single leaf, the spectral reflectance in leafstalk was higher than the spectral reflectance in edge of leaf. The action of derivative spectra on eliminating background influence on cotton canopy spectra and that of vegetation indices on determining agricultural parameters were analyzed. The results show that the position and slope of red edge of canopy spectral reflectance of cotton are certainly correlative to fractional vegetation cover.

The Digital Elevation Model (DEM) are terrain elevations at regularly spaced horizontal intervals, i.e., an a grid of regularly spaced elevations. With the development of computing technology, the methods of data acquisition, data storage and data processing speed for DEMs get along well. Heihe river lies in the northwest of China and is a continental river. It roots from snow-ice and disappears in deserts. The drainage area is about 140,000 square kilometers and the river is the main water source for the living. The upper reaches are mountainous and the runoff is very important. The middle reaches are oasis. At present, many hydrological and ecological models are introduced. The catchment basin and stream network data acquired from DEMs are main input data for many surface hydrological models. So the quality and resolution of DEMs are significant. Software ENVI Version 4.2 furnishes with the DEMs Extraction Module. The paper compared several methods for extracting DEMs of the upper reaches. We extracted the elevation data from the ASTER---stereo images with the module and created the DEM. Secondly; we collected the DEM based on the contour map of Heihe river. The comparison of the DEMs quality was carried out between the DEM from the contour map, the DEM extracted by ENVI Version 4.2. To a certain extent, the DEM from Aster imagery can reflect the terrain and be used in hydrological models.

Clouds are the obstruction of visual and infrared remote sensing and their shadows may also lead up to an intolerable bias of the true reflectance of the underlying terrain elements. Thus a reliable cloud and shadow mask is essential before the further processing. Clouds cast shadows on the earth's surface. On the high resolution remote sensing images, clouds' profiles and their shadows' are resemblant. Based on this truth, we employed a robust image matching algorithm called Modified Partial Hausforff Distance( MPHD ) to find the match with every cloud and its shadow and finally calculated the pixel distance between them. Before the match task we took into account topologic relationships such as coverage and fragmentation to improve the match result. Not only were the match pairs detected but also the pixel distances from each cloud to its shadow were obtained. Then we can use a pixel distance to predict a shadow of a cloud by translating the cloud. Given sunbeam's direction and viewing angles we may get cloud height with simple geometry calculation.

The marine waters of the Yellow Sea and East China Sea cover a large area and represent an important fishing ground. Monitoring changes in their biological productivity is an important goal that can hopefully be reached using satellite remote-sensing. Operational ocean color satellite algorithms are generally successful over the open ocean. These algorithms are based upon simple band ratios, assuming that the only optically active component of any significance in the water is phytoplankton. While this assumption generally holds for the open ocean waters, it may not always be the case for coastal ecosystems (in what are commonly referred to as Case II waters). This problem is particularly evident in the study site. For the high concentration of SPM, it make the failure of the atmospheric correction algorithm and decrease the accuracy of the products of ocean color remote sensing, such as the SeaWiFS and MODIS. In order to develop the high accuracy regional algorithm, the inherent optical properties in Yellow Sea and East China Sea must study previously. In this paper, the absorption and scattering properties of the optically significant biogeochemical variables and the composition of SPM are studied use the in situ dataset of the inherent optical properties in the Yellow Sea and East China Sea.

A study of detecting the sea fog from NOAA-16, and -17 Advanced Very High Resolution Radiometers (AVHRR3) is presented. Sea fog occurs frequently over China Sea at different season, especially on spring, and forms an obstacle for sea traffic. In this paper, several sea fog events are selected, analyzed and compared; their radiance and texture characterization with other bodies from satellite observations is given. Firstly, It is found that the satellite measured reflectance of channel 3a (1.58-1.64μm) is between the channel 1(0.58-0.68μm) and channel 2(0.725-1.0μm), and the one of channel 2 is lowest, which is different from the ocean, the land and some cloud body. Those results are explained with Mie scatter theory. Secondly, the sea fog, which is the cloud clung the earth surface, is generally characterized by higher reflectance than the surrounding water in visible, while it is similar to the surrounding in the infrared radiance brightness temperature. According those different feathers, a parameter, which is the standard deviation of the reflectance (or brightness temperature) differences between the adjacent eight pixels and the one, is defined as the texture to detect the marine fog. Thirdly, the sea fog is often coherent and continuous in spatial. It could be used to modify and restore some misjudge point or segment. Based on those analyses, finally, we design an algorithm for detect the sea fog at day. The results show that this method is valid to extract the fog region from NOAA/AVHRR3.

Before MODIS products will be applied in rice monitoring, it need to be validated. A site-intensive MODIS product validation on rice planting region in southern China was performed. Validation approach involved scaling up independent fine-grained datasets, including ground and high spatial resolution imagery (Thematic Mapper), to the coarser MODIS spatial resolutions. Results showed that The difference between situ rice LAI and MOD15-LAI in different rice growth sage is different. The differences are bigger in booting stage, heading stage and milking stage, but smaller in tiller stage and maturing stage. The 16-day composited MODIS reflectance and VIs matched well with ground measurement reflectance and VIs. Otherwise, results indicate that the MODIS algorithm will underestimate LAI value by about 5-10 % in total from 1-km resolution data over the Situ rice LAI at Southern China, the mean and standard deviation deviated from MOD15-LAI are smaller than that of situ rice LAI.

The first 19 bands of MODIS, covering visible to shortwave infrared spectral wavelength, were simulated by the ground-level reflectance spectra. All Normalized Difference Vegetation Index (NDVI)-like and Ratio Vegetation Index (RVI)-like spectral indices formed by every two bands were calculated to obtain their determinate coefficients with theoretical and real yield. Results showed that combinative NIR-infrared index (b2, b19) and (b16, b19) of MODIS were strongly correlated with rice yield, specially the correlative coefficient exceeded the significant level in maturing stage, but combinative visible light index were strongly correlated with rice yield in early stage and poorly in late stage. The best spectral index were the combination of (b2, b19) and (b16, b19) in predicting rice yield in whole rice growth, if considering the spatial resolution, Enhanced Vegetation Index (EVI) was better than the two band combination of (b2, b19) and (b16, b19) and was best suitable for monitoring rice yield.

In recent years hyperspectral remote sensing has been widely used in the applications of geology agriculture forest ocean etc. This work assessed the feasibility of hyperspectral technique in coastal zone remote sensing. Data was acquired by Operational Modular Imaging Spectrometer (OMIS). Field spectrum of each class was measured and analyzed to extract certain spectral feature. We proffer a hybrid decision tree classification algorithm combined with optimum spectral features of class pairs to every tree node and step by step classified out coastal vegetation water body rocky shore sand beach mudflat and artificial objects etc. The results show that hyperspectral data can be used to classify coastal landscape more accurate than multispectral image.

The calculation of Rayleigh scattering radiance is the first step of the atmospheric correction of ocean color remote sensing which affects the quality of atmospheric correction significantly. This paper studies how the satellite attitude affects the accuracy of the Rayleigh scattering radiance calculation. Satellite attitude affects the geometry angles of the sun and sensor directly and then affects the Rayleigh scattering radiance. The results show that roll angle affects Rayleigh scattering calculation most and the relative error of Rayleigh scattering radiance calculation is up to 10 as the roll angle is 2.5°. However the effects of the pitch angle and yaw angle are very small and the relative error of Rayleigh scattering radiance calculation is less than 1% as the pitch angle or yaw angle is 2.5°. The results also show that in order to achieve the 1% accuracy goal of the Rayleigh scattering radiance calculation the satellite roll angle should be less than if the satellite attitude isn't corrected in the data pre-processing stage of ocean color remote sensing.

The airborne test experiment validates the function of remote sensor before on-oribt which has important meaning for satellite remote sensing. The sun glint is the most important factor that affects the data quality of airborne test experiment. In order to avoid the sun glint and improve the data quality it needs to select the optimal fly route before the airborne test experiment. This paper simulates the sun glint radiative image with inputed the in-remote sensor atmosphere and water parameters using the radiative transfer theory in atmosphere and ocean. Based on the generated sun glint radiative images can select the optimal fly route will improve the data availability significantly in the airborne test experiment and reduce the waste of manpower and material resources in the airborne test experiment.