International Journal of Remote Sensing and Earth Sciences (IJReSES)
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MONITORING OF LAND USE CHANGES USING AERIAL PHOTOGRAPH AND IKONOS IMAGE IN BEDUGUL, BALI
Get PDFThere was change of expending land use in Bedugul. It is necessary to monito the change of highland of Bali, catchments area of Beratan, Buyan and Tamblingan lakes. In order to control land use change and to anticipate degradation of hydrology function of this area. This study is to monitor the land use change by remote sensing and GIS technique. To evaluate land use and land cover, aerial photograph imagery and Ikonos imagery were used. Over 22 years of observation (1981-2003), there was land use changes in the catchments area of Beratan, Buyan and Tamblingan lakes at Bedugul area. The area of settlement increased by 62.6 ha, dry land vegetable crops and forest decreased by 116.5 ha and 32.5 ha, respectively. The surface area of Buyan Lake was also decreased, due to sedimentation caused by erosion in the vegetables dry land crops. Planning the land use study on erosion and soil-water conservation in this area necessary, in order to control land use change, erosion, and sedimentation in the lakes. Keywords: land use, monitoring, aerial photograph, Ikonos image
APPLICATION OF WAVELET TRANSFORM FOR INTERNAL WAVE DETECTION IN SAR IMAGE
Get PDFIn this paper, wavelet transform based on dyadic scales and spatial location have been used for internal wave detection in SAR image. It performed by using multi resolution analysis of image for feature detection and image enhancement. Wavelet transform uses local analysis to analyze a shorter region in image in time and scale data allows precise information than time and frequency region analysis such as Fourier analysis. Internal wave is observed in SAR image by effect of Bragg scattering process in sea surface that represents the meso-scale feature of sea processes. SAR image data is used considering to the effectiveness of large scales area monitoring on near real time data. Internal waves were observed in ERS-1 per 2 SAR images data over Lombok Strait during 1996-2001 period using 2D Symlet analysis for the symmetric extension of data at the image boundaries, to prevent discontinuities by a periodic wrapping of data in fast algorithm and space-saving code. Lombok Strait is chosen as study area because this strait is a major passage of the flow from Pacific Ocean to Indonesian seas (ARLINDO) and passage of Indian Ocean Kelvin wave to Makassar Strait.
Keyword: SAR image, internal wave, wavelet analysis
PRESENT UNDERSTANDING OF ACEH TSUNAMI (APPLICATIONS OF DATA FROM FIELD TO SATELLITE OBSERVATIONS)
Get PDFApplication of data from field to satellite observation and simulation has been made as present understanding of Aceh tsunami. Tsunami has attracted attention after struck Aceh in December 26th 2004, generated by a strong eartquake with magnitude Mw=9.0. The eatrhquake triggered giant tsunami waves that propagated throughout the Indian Ocean, causing extreme inundation and destruction along the northern and western coast of Sumatra. Within hours, the tsunami devastated the distant shores of Thailand to east as well as Sri Lanka, India and Maldives to the west. The tsunami also caused deaths, and destruction in Somalia and other nations of East Africa. The tsunami was recorded on tidal stations throughout the Indian Oceans in worldwide. Unlike the Pacific, the Indian Ocean does not yet have a network of deep-ocean pressure sensors, and so coastal tide gauges provide the only direct measurement of Indian Ocean stunami amplitudes. We had many lessons and basic knowledge which had already been learned from this tragic event in the Indian Ocean. Many more lessons should be learned in the near future as this tragedy unfolds and reverals many failures to value and protect human life in this neglected region of the world. Keywords: Tsunami, Earthquake, Indian Ocean, Aceh
THE CHARACTERISTIC AND VARIABILITY OF SEA SURFACE TEMPERATURE IN JAVA SEA
Get PDFThe phenomena of marine climate can be identified by the sea surface temperature, as Illahude (1999) reported that one of the parameters of oceanography which characterized of sea water mass is sea surface temperature (SST). The distribution of sea surface temperature can be used as an indicator of fishing ground. However, as understanding of marine climate variability it does not well enough (Hartoko,2000). The characteristic and variability of ST in Java Sea are not sufficiently enough understood. In order to better understand, we need the Spatial-Temporal Analysis of SST. The Spectral Analysis Method is used to study the characteristic and seasonal variation of SST, while GIS Analysis is used to study SST spatial distribution pattern. Temporally, the highest temperature at Java Sea occurs in April-May and November, whereas the lowest temperature in February and August. The SST fluctuation of Java Sea ranges from 27.48 degree of celcius to 29.66 degree of celcius and its periodic cycle generally occurs for 6 months, 1 year and 8 years. Keyword: SST, Variability, Spatio-Temporal Analysi
VERTICAL DISTRIBUTION OF CHLOROPHYLL-A BASED ON NEURAL NETWORK
Get PDFAn algorithm of estimating Vertical distribution of Chlorophyll-a (Chl-a) was evaluated based on Artificial Neural Networks (ANN) method in Hokkaido field in the northwest of Pacific Ocean. The algorithm applied to the data of SeaWiFS on OrbView-2 and AVHRR on NOAA off Hokkaido, has been applied on September 24, 1998 and September 28, 2001. Ocean color sensor provides the information of the photosynthetic pigment concentration for the upper 22% of the euphotic zone. In order to model a primary production in the water column derived from satellite, it is important to obtain the vertical profile of Chl-a distribution, because the maximum value of Chl-a concentration used to lie in the subsurface region. A shifted Gaussian model has been proposed to describe the variation of the chlorophyll-a (Chl-a) profile which consists of four parameters, i.e. background biomass (B0), maximum depth of Chl-a (zm), total biomass in the peak (h), and a measurement of the thickness or vertical scale of the peak (cr). However, these parameters are not easy to be determined directly from satellite data. Therefore, in the present study, an ANN methodology is used. Using in-situ data from 1974 to 1994 around Japan Islands, the above four parameters are calculated to derive the Chl-a concentration, sea surface temperature, mixed layer depth, latitude, longitude, and Julian days. The total of 6983 profiles of Chl-a and temperature are used for ANN. The correlation coefficients of these parameters are 0.79 (B0), 0.73 (h), 0.76 (cr) and 0.79 (zm) respectively. A site called A-linc off Hokkaido is used to evaluate Chl-a concentration in each depth. After comparing with in-situ data and ANN model, the results show good agreement relatively. Therefore, the ANN method is applicable and available tool to estimate primary production and fish resources from the space.
Keywords : Ocean color, Chlorophyll-a (Chl-a), Vertical structure, Artificial Neural Networks (ANN)
SPATIAL MODELING FOR MARICULTURE SITE SELECTION BASED ON ECOSYSTEM PARAMETERS AT KUPANG BAY, EAST NUSA TENGGARA INDONESIA
Get PDFThe aims of the study were : a. to identify the physical, chemical and biological parameters at the utilization zone-coastal water of Kupang Bay, East Nusa Tenggara, b. to analyze the value of coastal water suitability from the physical, chemical and biological parameters for the development for maniculture at the utilization zone of Kupang Bay, East Nusa Tenggara, c. to select the sub zone for the sea weed culture, grouper fish culture site using the system of floating net cage and the culture of pearl oyster. The method used in the study is a spatial approach by conducting the direct measurement of the physical, chemical, and biological parameters. Mapping and spatial model was processed and analyzed through a geo-statistic method. The site selection for mariculture sub-zones were constructed through a spatial scoring and spatial interaction-RGB model and based on matrix of ecosystem parameters suitability score and weighting. With consideration that any numerical, mathematical or spatial model related to the surface of the earth or an ecosystem should take into account the concept of 4D function of its spatian distribution (x,y,z)and temporal consideration (time) such as seasonal data. The result showed that the range values of the physical, chemical, and biological parameters at utilization zone of the Kupang Bay are as follow: 1. Variable of physical parameters were: a). depth 5-25 m, b). transparancy 3.00-11.00 m, c). temperature 26-28.45 degree of celcius, d). salinity 31.50-38.20 ppt, e). substrate consist of: sand, sandy clay, clay sand, silt clay, silt, sand, and coral, f). current velocity 0.059-0.238m per s, and g). total suspended solid 180-305mg per l. 2. Variable of chemical parameters were: a). dissolved oxygen 6.85-8.74 ppm, b). pH 7.97-8.59, c). phosphate is 0.081-0.435mg per l, and d). nitrate 0.145-4.134 mg per l, 3. Variable of biological parameter were: a). abundance of phytoplankton 106,760-210,380 cell per l, and b). chlorophyll-a 0.033-0.037 mg per m. Sub zone for seaweed culture identified mainly almost at all area of the middle of the Kupang Bay width about 7,544 hectares. The most-suitable sub-zone for grouper fish culture was 2,803 hectares wide and width of 1,336 hectare of moderately-suitable. Sub zone for pearl culture exist especially at the north part of Kupang Bay and at some area nearby at the mouth of the Kupang Bay wide about 4.383.8 hectares. The approach with the above concept had proved that with a significance difference of scoring-weight on each specific and important ecosystem parameters for each spatial analysis purposes (i.e.50 percent scoring-weight of nitrate and phosphate for sea weed culture sub zone; 40 percent scoring-weight of dissolved oxygen for fish culture sub zone and 40 percent scoring weight of plankton abudance for oyster pearl culture sub zone), had resulted in a distinctive and specific delineation for each culture sub zones, thus avoiding and less on sub zonal overlapping. Keywords: Ecosystem parameters, Kupang Bay, Mariculture, Spatial model
CLASSIFICATION OF POLARIMETRIC-SAR DATA WITH NEURAL NETWORK USING COMBINED FEATURES EXTRACTED FROM SCATTERING MODELS AND TEXTURE ANALYSIS
Get PDFThis paper shows a study on an alternative method for classification of polarimetric-SAR data. The method is designed by integrating the comined features extracted from two scattering models(i.e., freeman decomposition model and cloud decomposition model) and textural analysis with distribution-free neural network classifier. The neural network classifier (wich is based on a feedforward back-propagation neural network architecture) properly exploits the information in the combined features for providing high accuracy classification result. The effectiveness of the proposed method is demonstrated using E-SAR polarimetric data acquired on the area of Penajam, East Kalimantan, Indonesia. Keywords: Polarimetric-SAR, scattering model, freeman decomposition, Cloude decomposition, texture analysis, feature extraction, classification, neural networks
NUMERICAL SIMULATION OF COHESIVE SEDIMENT TRANSPORT IN JAKARTA BAY
Get PDFThe 3D-numerical model has been applied to simulate the current circulation and cohesive sediment transport in the Jakarta Bay, Indonesia. Sediment load comes from 3 river mouths i.e. Angke River, Karang River, and Ancol River. The model was simulated to analyze the effect of tidal current and river discharge. A constant westerly and easterly wind was used as input of the model to see the influence of monsoonal season. The numerical result showed that the tidal current flows from east to western part of the bay during ebb tide and vice versa during flood tide. The surface current circulation was dominantlyinfluenced by the tidal current comparated with the wind and river discharge effects. Hight turbidity level was found near the river mounths with the range of 50 to 100 mg per l. This high in the offshore area of the bay the sediment concentration decreases up to 10 mg per l. The movement of sediments followed the current circulations. During the flood tide, the sediment concentratation from the mounth of Angke River moved to the western part of the bay. Model simulated for increasing the river discharge into two times showed that the sediment distributed to the offshore direction two time longer compare with the normal debit. The transport of sediment from the Angke and Karang Rivers to the offshore area reached up to 6 km, while it just reached plus minus 2,5 km from the Ancol River. Keyword: Numerical model, Cohesive sediment, Effect of tidal current and river discharge
THE INDIAN SUMMER MONSOON CONTRIBUTION TO THE JJA RAINFALL OVER THE NOTERN PART OF SUMATRA DURING THE CO-OCCURING EL NINO AND DIPOLE MODE (+) YEARS
Get PDFThis article describes the further study investigating the JJA rainfall formation in the northern part of Sumatra during the co-occuring El Nino and Dipole Mode (+) years. Analyses based on wavelet transformation reveal that the rainfall in that part of Sumatra is insensitive or at least insignificantly influenced by El Nino and or DM. This study confirms also that the Indian Summer Monsoon (IM) may play important roles in the rainfall budget of the region including in compensating the possible reduction effects of both El Nino and DM on the JJA rainfall. The characteristics of JJA rainfall over the northern part of Sumatra on a wavelet time-frequency plane are descreibed, and the relative contributions of EN-DM-Indian summer monsoon in the rainfall over the nothern part of Sumatra are demonstrated by using multicoliner statistical analysis. Keywords: Indian Summer Monsoon, Rainfall, El Nino, Dipole Mode
