International Journal of Remote Sensing and Earth Sciences (IJReSES)
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VERIFICATION OF LAND MOISTURE ESTIMATION MODEL BASED ON MODIS REFLECTANCES IN AGRICULTURAL LAND
Get PDFFrom this research, it is found that reflectances in the first, second, and sixth channels (R1, R2, R6) of MODIS have high correlations with surface soil moisture (percent weight) at 0-20 cm depth. An index called Land Moisture INdex (LMI) was created from the linier combination of R1 (percent), R2(percent), and R6 (percent). The MODIS reflectances and field soil moisture in paddy field taken from the Central and East Java during Juli-September 2005 are applied into the previous model which have been generated from data during July-September 2004. The result showed that there was a high correlation between Land/Soil Moisture (SM) which was measured from field survey, and LMI which was generated from the MODIS refectances. The best model equation between SM and LMI is the power regression model, which has the coeficient of determination of 88 percent. It is implied that soil moisture condition can be obtained from the MODIS data using LAnd Moisture Index. Therefore, the spatial information of drouht condition analysed throught the soil moisture in the agricultural land can be provided from the MODIS data. Keywords: Land Moisture Index, Soil Moisture Estimation, Spatial information, drought
ESTIMATION OF AIR TEMPERATURE USING REMOTE SENSING BASED ON THERMAL DIFFUSIVITY APPROACH
Get PDFThe measurement of air temperature usually used thermometer in the meteorology or climate station under Bureau of Meteorology and Geophysics. In Indonesia, there are some limitations in air temperature measurement and then they could not provide the spatial high resolution information. The measurement of air temperature is very important for analyzing the human comfort, photosynthesis, and vegetation growth which we need saome details spatial information. However, when data were sparse, the underlying assumptions about the variation among sampled points often differed and the choice of interpolation method and parameters then became critical. Often though data may be too sparse to use any of the interpolation methods, alternate ways to derive spatially representative values of air temperature need to researched. The data that could provide spatial information are remote sensing. The objective of this research is to estimate air temperature using remote sensing data (NOAA/AVHRR and LANDSAT/TM), based on thermal diffusivity approach. The steps of this research include the calibration of surface temperature, the determination of amplitude, and the estimation of air temperature. Based on this research, the best equation to calculate surface temperature from NOAA AVHRR is Ulivieri et al equation. This equation shows the higher correlation between surface temperatures from NOAA/AVHRR and the observation in the field than the other equation. Physically, this research could estimate air temperature from satellites data, but statistically, this research has not enough significancy to describe the field observation. Keywords: physical model, temperature, remote sensing
SEA SAND MINING ZONATION THROUGH THE INTEGRATION OF OCEAN DYNAMIC AND GIS IN RIAU ISLAND WATERS
Get PDFSea-sand mining has both advantages particularly in its destructive capabilities. The damages caused by sea-sand mining are mostly due to the unorganized mining zones. In order to minimize the negative effects of mining activities, the well-organized mining zones that have evaluated all related aspects are required. There are several aspects which are closely related to the sea-sand mining zones , one of those is hydro-oceanography aspects in its relation with the sea environments. A comprehensive analysis can be made by integrating hydrooceanography and GIS as a system of both data-organizer and software. This method is supported by using the remote sensing technology as a verification data comparison to the results of hydrooceanography analyses. The application of image analysis as a verification tool is a good method to proof the results given by the numerical simulation model. In this study, we use the Landsat images as the data analysis have indicated that the mining can be continously conducted in several locations without imposing any hazardous impacts to the adjacent environment. By considering the results above, in integrated system between the numerical model and the GIS in highly effective as a foundation to determine the mining zone where the negative effects of the oceanographic-dynamical-changes on the environment due to the mining activities can be easily recognized and predicted. Keyword: Geographic Information System, Hydro-oceanography, Image Analysis
STUDY OF SHORT MACKEREL CATH, SEA SURFACE TEMPERATURE, AND CHLOROPHYLL -A IN THE MAKASSAR STRAIT
Get PDFThe Makassar Strait is the major fishing ground for Short Mackerel (Rastrelliger spp) fisheries in South Sulawesi, Indonesia using both commercial fishing vessels and boats with traditional fishing gear. Though Short Mackerel is one of dominant commercial food fishes in South Sulawesi, the annual Cath per Unit Effort (CPUE) has been decreasing from year to year. In 2000, the total of annual CPUE was 22,117 tons and in 2007, it was 17,596 tons. The purpose of this research was to forecast the fishing ground of Short Mackerel employing Moderate Resolution Imaging Spectroradiometer (MODIS) satellite images in Makassar Strait territory with the study interest of 3 S and to 5 S and 118 E to 120 E. This research was conductade from September 15 to October 20, 2007. Fishing data were collected from the fishermen including fishing locations, catch, sea surface temperature, and chlorophyll concentrations. To determine the relationship between cacth and oceanographic parameters, linear regression was employed. We also examined sea surface temperature (SST) and Chlorophyll-a concentration field data vs. MODIS satellite data. The result showed that SST andChlorophyll distributions have close relationship with the distribution of fishing location of Short Mackerel. The fishing location tends to spread on the waters with the SST ranged from 26 degree of celcius to 29 degree of celcius and Chlorophyll concentration from 1.19 mg per m to 1.25 mg per m. Keywords: Chlorophyll-a, MODIS, Sea Surface Temperature
MAPPING CORAL REEF HABITAT WITH AND WITHOUT WATER COLUMN CORRECTION USING QUICKBIRD IMAGE
Get PDFRemote sensing from space offers an effective approach to solve the limitation of field sampling, in particular to monitor the reefs in remote sites. Moreover, using the achieved remotely sensed data, it is even possible to monitor the historic status of the coral reef environment. The capabilities of satellite remote sensing techniques combined with the field data collection have been assessed for generating coral reef habitat mapping of the Derawan Island. A very high spatial resolution multi-spectral QuickBird image (October 2003) has been used. The capability of QuickBird image to generate a coral reef habitat map with the water column correction by applying the Lyzenga method, and also without the water column correction by the applying maximum likelihood method, have been
assessed. The classification accuracy of the coral reef habitat map increased after the improvement of the water column effects. The classification of QuickBird image for coral reef habitat mapping increased up to 22% by applying a water column correction. Keywords : Coral Reef, Quickbird, Water Column Correctio
RELATIVE HUMADITY ESTIMATION BASED ON MODIS PRECIPITABLE WATER FOR SUPPORTING SPATIAL INFORMATION OVER JAVA ISLAND
Get PDFThis research is performed to derive weather property, i.e. relative humidity, based on precipitable water from MODIS (Moderate Resolution Imaging Spectroradiometer) data which on board of TERRA/AQUA satellites. As one of dynamic atmospheric parameters, the precipitable water has ability to indicate the dryness or wetness of a certain area. It can be derived by MODIS at 0.865, 1.24, 0.905, 0.936 and 0.940 um of its wavelength ranges. Verification of MODIS precipitatble water is made using radiosonde data at 2 climatological stations in Java island (Jakarta and Surabaya). The result shows that the standard deviation between precipitable water which is derived by MODIS and radiosonde data (August-October 2004), is 1.6 cm, Meanwhile, through the statistical analysis, they have significant correlation of about 0.82. In adition, the relationship between the MODIS precipitable water and the altitude has a negative correlation (r= -0.98). It means that the precipitable water tends to decrease along with the increase of altitude, According to the climate condition in West Java which is mostly wetter rather than of East Java, we knew that the precipitable water in West Java is higher than East Java. Related to related to relative humidity, the mODIS precipitable water can be used to estimate relative humidity, based on topography area, the correlation coeficient between 0.84-0.92. Keywords: MODIS Precipitable water, Radiosonde, Relative humidity, Verification
COMPARISON OF CHLOROPHYLL CONCENTRATION ESTIMATION USING TWO DIFFERENT ALGORITHMS AND THE EFFECT OF COLORED DISSOLVED ORGANIC MATTER
Get PDFThe effect of colored dissolved organic matter (CDOM) on the Sea-viewing Wide Field-of-view Sensor(Sea WiFS) OC4v4 and the MODIS algorithms used to estimate chlorophyll-a was studied using satellite and situ data collated during seasonal cruises in the Northeastern Gulf of Mexico between 1997 and 2000. For chlorophyll-a concentrations 50 mg m, OC4v4 generally overestimated chlorophyll-a concentration by up to 300 percent. The MODIS algorithm provided better estimates of high CDOM concentration, found typically nearshore in noterhn summer and spring. For oceanic waters where chlorophyll-a concentrations 1.0 mg m, both OC4v4 and MODIS algorithm had errors within the Sea WiFS mission specification (35 percent) during fall. The OC4v4 algorithm is more susceptible to artifacts due to CDOM absorption of light at 443 mm. Keywords: chlorophyll-a, Mississippi River Plume, Sea WiFS, upwelling, OC4v4
WATER MASS ANALYSIS OF THE INDONESIAN THROUGHFLOW BY MEANS OF PRINCIPLE COMPONENT ANALYSIS
Get PDFThe water masses in both routes of Indonesia Throughflow (ITF) from historical hydrographic data are examined by means of the Principal Component Analysis (PCA), a multivariate statistical technique, during the southeast monsoon and northwest monsoon, and compared with the TS diagrams. The temperature and dissolves oxygen always play in the same PC, which describeds a variability contribution of the water mass characters, while salinity in a different PC. The relationship of the water masses parameters may indicate the character of dissolved oxygen as a non-conservation tracer. The Principle Component Analysis may also be used to follow the trendds of core layer attenuation as verified by the salinity corresponds at the PC. It will be higher with S-max and S-min and more closely resemble the sources. This condition is shown in the waters close to the main sources in the Pacific, like Sulawesi, Malkuku and Halmahera Sea, where both the salinity extrema can still be observed. Conversely, in the Banda and Timor Sea, where S-max and S-min are greatly attenuated even completely remove, the correspondence of salinity in the water mass character variability becomes smaller. As seen on TS and TO diagrams, PCA graphics are also showed the dominant of the north Pacific water in the western route seas, the Sulawesi, Makasar Strait and the Florest Sea, but relatively salty water of South Pacific origin is observed in the Halmahera Sea, particularly in the northwest monsoon. The strong seasonal variablity of surface water in the Indonesian can also be observed in the PCA graphics. Keywords: Water Mass, Indonesian Throughflow, PCA
TWO VIEWING THEORY ON ATMOSPHERE CORRECTION IN OCEAN COLOR ALGORITHM
Get PDFA new algorithm for retrieving optical thickness and surface reflectance, data in the visible bands from satellites is developed. The proposed algorithm is to solve the simultaneous equation of two unknown variables, i.e. aerosol optical thickness and surface reflectance (r). In term of difference from the conventional and, one directional retrieval algorithm, we do not need the spectral characteristics of aerosol. We solve the equation by forward calculation using the 6S transfer code. The two observational equations change linearly within the domain where we solve the solution. We estimate the chlorophyll-a concentration from the evaluated r. This method is validated against Global Imager (GLI) data, which has two independent data for one pixel in both tilting and nadir viewing. Keywords, GLI, 6S, Radiative Transfer, Reflectance, Rayleigh, Mie
POLARIMETRIC-SAR CLASSIFICATION USING FUZZY MAXIMUM LIKEHOOD ESTIMATION CLUSTERING WITH CONSIDERATION OF COMPLEMENTARY INFORMATION BASED ON PHYSICAL POLARIMETRIC PARAMETERS, TARGET SCATTERING CHARACTERISTIK, AND SPATIAL CONTEXT
Get PDFThis paper shows a study on an alternative method for unsupervised classification of polarimetric-Syenthetic Aperture Radar (SAR) data. The first step was to extract several main physical polarimetric parameters (polarization power, coherence, and phase difference) from polarimetric covariance matrix (or coherency matrix) and physical scattering characteristics of land use/cover based on polarimetric decomposition (Cloude decomposition model). In this paper, we found that these features have complementary information which can be integrated in order to improve the discrimination of different land use or cover types. Classification stage was performed using Fuzzy Maximum Likelihood Estimation (FMLE) clustering algorithm. FMLE algorithm allows for ellipsoidal clusters of arbitrary extent and is consequently more flexible than standard Fuzzy K-Means clustering algorithm. Hoever, basic FMLE algorithm makes use exclusively the spectral (or intensity) properties of the individual pixel vectors and spatial-contextual information of the image was not taken into account. Hence, poor(noisy) classification result is ussualy obtained from SAR data due to speckle noise. In this paper, we propose a modified FMLE which integrate basic FMLE clustering with spatial-contextual information by statistical analysis of local neightbourhoods. The effectiveness of the proposed method was demonstrated using E-SAR polarimetric data acquired on the area of Penajam, East Kalimantan, Indonesia. Result showed classified images improving land-cover discrimination performance. Exhibiting homogeneous region, and preserving edge and other fine structures. Keywords: Cloudes polarimetric decomposition, FMLE clustering, polarimetric coherence, Polarimetric-SAR, unsupervised classification