Normal.dotm 0 0 1 214 1220 University of Sriwijaya 10 2 1498 12.0 0 false 18 pt 18 pt 0 0 false f... more Normal.dotm 0 0 1 214 1220 University of Sriwijaya 10 2 1498 12.0 0 false 18 pt 18 pt 0 0 false false false Sea surface height (SSH) data from merged-satellite observations (e.g. TOPEX/Poseidon, JASON and ERS) were used to evaluate the spatial and temporal variations of sea surface circulations in the southeastern tropical Indian Ocean (SETIO). A Complex Empirical Orthogonal Function (CEOF) was used to extract the dominant mode of variability in the SETIO region. The results show that the first mode accounts for 41.2% of the total variance dominates the variation. The second mode accounts for 18.2% of the total variance, while the third and the fourth modes explain 6.5% and 2.6% of the total variance, respectively. The spectrum analysis indicates that the 35-day variations is a prominent feature in all CEOF modes. Furthermore, semiannual variation at period of about 180-day was observed in the first third modes, while the annual variation of about 300-day was only observed in the first two modes. A relatively strong variation at period of around 500-day was observed in the first, second and fourth modes. It is suggested that the spatial and phase pattern of the first and third modes are related to the propagation of the Kelvin waves generated by wind stress over the equatorial Indian Ocean. On the other hand, the second was likely related to the local upwelling and downwelling generated by the seasonal changes in the alongshore winds. Furthermore, the fourth mode represents the oceanic eddy generated from the downstream straits of the Indonesian Throughflow. Variasi Spasial dan Temporal Tinggi Muka Laut di Wilayah Tropis Samudera India Bagian Tenggara Berdasarkan Data Satelit Altimetri Abstrak Data tinggi permukaan laut hasil observasi dari beberapa satelit (yaitu: TOPEX/Poseidon, JASON dan ERS) digunakan untuk evaluasi variasi spasial dan variasi temporal sirkulasi permukaan laut di wilayah tropis Samudera Hindia bagian tenggara. Analysis dilakukan menggunakan metode Complex Empirical Orthogonal Function (CEOF) untuk mendapatkan mode variasi yang dominan di wilayah ini. Hasil analisis menunjukkan bahwa mode CEOF pertama menjelaskan 41,2% dari variasi total dan merupakan mode yang paling dominan. Mode CEOF kedua mengandung 18,2% dari variasi total, sedangkan mode ketiga dan keempat menjelaskan masing-masing 6,5% dan 2,6% dari variasi total. Analisis spektrum terhadap deret waktu masing-masing mode CEOF menunjukkan bahwa variasi dalam skala 35 hari merupakan variasi yang signifikan untuk setiap mode. Selanjutnya, variasi setengah-tahunan dengan periode osilasi sekitar 180 hari terekam pada tiga mode pertama, sementara variasi tahunan dengan periode osilasi sekitar 300 hari hanya terekam pada mode pertama dan mode kedua. Variasi yang cukup kuat pada periode osilasi sekitar 500 hari terekam pada mode pertama, mode kedua dan mode keempat. Hasil analisis ini juga menunjukkan bahwa pola spasial dan fase gelombang pada mode pertama dan mode ketiga adalah terkait dengan penjalaran gelombang Kelvin yang dibangkitkan oleh stres angin di wilayah ekuator Samudera Hindia. Sementara itu, mode kedua terkait dengan proses upwelling dan downwelling yang dibangkitkan oleh angin muson di sepanjang pantai. Selanjutnya, mode keempat merepresentasikan oceanic eddy yang terbentuk dari selat-selat arus lintas Indonesia (ARLINDO). Kata kunci: Complex empirical orthogonal function, Analisis Fourier, Samudera Hindia, Tinggi permukaan laut.
Karimata Strait is a vast strait which connecting the South China Sea to the Java Sea and has a g... more Karimata Strait is a vast strait which connecting the South China Sea to the Java Sea and has a geostrategic function. This study aims to determine oceanographic characteristics in the Karimata Strait which includes wave, current and tidal conditions. The data used is derived from National Oceanic and Atmospheric Administration (NOAA) and Babel Ocean Observation Science and Technologies Centre (BOOST CENTRE). This research is focused on oceanographic conditions in the eastern monsoon (August 2017). The analysis shows the current direction in the Karimata Strait has speed between 0 – 0.25 m/s to the northwest. The wave height in the southern waters of the Karimata Strait tends to be higher between 0.175 – 0.225 m. Furthermore, the tides in Karimata Strait has a diurnal type with formzahl numbers is F=12.33 and tidal mounts is 2m.
The existence of the Indonesian government's One Map Policy (OMP) demands synergy to the regi... more The existence of the Indonesian government's One Map Policy (OMP) demands synergy to the regions. Sumatra is one of the areas that captures this opportunity. One of the follow-up actions to this policy is regional readiness in preparing qualified human resources in the geospatial field. Sriwijaya University as one of the universities in Indonesia that focuses on developing human resources in South Sumatra, facilitates local governments in developing employee capacity. This program was carried out for 5 days to learn about the basic level Geographic Information System (GIS) for Bappeda Lahat employees. This program is carried out in 3 stages, namely identification of partner problems, training, and evaluation. This training program has a positive impact on employees in Bappeda Lahat, namely being able to make location points for regional planning with SmartGPS, making spatial shapefile data and making thematic spatial maps according to the main tasks of the job fields of employee...
Dalam penelitian ini dilakukan pengkajian dinamika massa air Arus Lintas Indonesia (Arlindo) dala... more Dalam penelitian ini dilakukan pengkajian dinamika massa air Arus Lintas Indonesia (Arlindo) dalam kaitannya dengan sumber asli air yang dapat teridentifikasi masuk dari Samudra Pasifik ke perairan Indonesia Bagian Timur. Wilayah studi berada pada 12.5° LU – 2.5° LS dan 122,5° BT - 140° BT. Sumber data adalah World Ocean Database 2001 dari National Oceanography Data Center (NODC), http://www.nadc.noaa.gov/PC5/WODo1/pacif_o.html . Analisis dilakukan dengan menggunakan metode core layer dan analisis isopiknal sedangkan untuk mengolah dan menampilkan data digunakan software Ocean Data View mp versi 1.2, http://www.awi-bremerhaven.de/GEO/odv . Dari analisis yang dilakukan teridentifikasi bahwa sumber air Arlindo yang masuk ke Perairan Indonesia bagian timur melalui gerbang Arlindo memiliki karakteristik dari berbagai massa air, antara lain adalah core dari; NPSW dengan densitas potensial sekitar 24 s q salinitas 34.76 4 ml/l; SPSW dengan densitas potensial ekitar 25 s q salinitas S>3...
Normal.dotm 0 0 1 214 1220 University of Sriwijaya 10 2 1498 12.0 0 false 18 pt 18 pt 0 0 false f... more Normal.dotm 0 0 1 214 1220 University of Sriwijaya 10 2 1498 12.0 0 false 18 pt 18 pt 0 0 false false false Sea surface height (SSH) data from merged-satellite observations (e.g. TOPEX/Poseidon, JASON and ERS) were used to evaluate the spatial and temporal variations of sea surface circulations in the southeastern tropical Indian Ocean (SETIO). A Complex Empirical Orthogonal Function (CEOF) was used to extract the dominant mode of variability in the SETIO region. The results show that the first mode accounts for 41.2% of the total variance dominates the variation. The second mode accounts for 18.2% of the total variance, while the third and the fourth modes explain 6.5% and 2.6% of the total variance, respectively. The spectrum analysis indicates that the 35-day variations is a prominent feature in all CEOF modes. Furthermore, semiannual variation at period of about 180-day was observed in the first third modes, while the annual variation of about 300-day was only observed in the first two modes. A relatively strong variation at period of around 500-day was observed in the first, second and fourth modes. It is suggested that the spatial and phase pattern of the first and third modes are related to the propagation of the Kelvin waves generated by wind stress over the equatorial Indian Ocean. On the other hand, the second was likely related to the local upwelling and downwelling generated by the seasonal changes in the alongshore winds. Furthermore, the fourth mode represents the oceanic eddy generated from the downstream straits of the Indonesian Throughflow. Variasi Spasial dan Temporal Tinggi Muka Laut di Wilayah Tropis Samudera India Bagian Tenggara Berdasarkan Data Satelit Altimetri Abstrak Data tinggi permukaan laut hasil observasi dari beberapa satelit (yaitu: TOPEX/Poseidon, JASON dan ERS) digunakan untuk evaluasi variasi spasial dan variasi temporal sirkulasi permukaan laut di wilayah tropis Samudera Hindia bagian tenggara. Analysis dilakukan menggunakan metode Complex Empirical Orthogonal Function (CEOF) untuk mendapatkan mode variasi yang dominan di wilayah ini. Hasil analisis menunjukkan bahwa mode CEOF pertama menjelaskan 41,2% dari variasi total dan merupakan mode yang paling dominan. Mode CEOF kedua mengandung 18,2% dari variasi total, sedangkan mode ketiga dan keempat menjelaskan masing-masing 6,5% dan 2,6% dari variasi total. Analisis spektrum terhadap deret waktu masing-masing mode CEOF menunjukkan bahwa variasi dalam skala 35 hari merupakan variasi yang signifikan untuk setiap mode. Selanjutnya, variasi setengah-tahunan dengan periode osilasi sekitar 180 hari terekam pada tiga mode pertama, sementara variasi tahunan dengan periode osilasi sekitar 300 hari hanya terekam pada mode pertama dan mode kedua. Variasi yang cukup kuat pada periode osilasi sekitar 500 hari terekam pada mode pertama, mode kedua dan mode keempat. Hasil analisis ini juga menunjukkan bahwa pola spasial dan fase gelombang pada mode pertama dan mode ketiga adalah terkait dengan penjalaran gelombang Kelvin yang dibangkitkan oleh stres angin di wilayah ekuator Samudera Hindia. Sementara itu, mode kedua terkait dengan proses upwelling dan downwelling yang dibangkitkan oleh angin muson di sepanjang pantai. Selanjutnya, mode keempat merepresentasikan oceanic eddy yang terbentuk dari selat-selat arus lintas Indonesia (ARLINDO). Kata kunci: Complex empirical orthogonal function, Analisis Fourier, Samudera Hindia, Tinggi permukaan laut.
Karimata Strait is a vast strait which connecting the South China Sea to the Java Sea and has a g... more Karimata Strait is a vast strait which connecting the South China Sea to the Java Sea and has a geostrategic function. This study aims to determine oceanographic characteristics in the Karimata Strait which includes wave, current and tidal conditions. The data used is derived from National Oceanic and Atmospheric Administration (NOAA) and Babel Ocean Observation Science and Technologies Centre (BOOST CENTRE). This research is focused on oceanographic conditions in the eastern monsoon (August 2017). The analysis shows the current direction in the Karimata Strait has speed between 0 – 0.25 m/s to the northwest. The wave height in the southern waters of the Karimata Strait tends to be higher between 0.175 – 0.225 m. Furthermore, the tides in Karimata Strait has a diurnal type with formzahl numbers is F=12.33 and tidal mounts is 2m.
The existence of the Indonesian government's One Map Policy (OMP) demands synergy to the regi... more The existence of the Indonesian government's One Map Policy (OMP) demands synergy to the regions. Sumatra is one of the areas that captures this opportunity. One of the follow-up actions to this policy is regional readiness in preparing qualified human resources in the geospatial field. Sriwijaya University as one of the universities in Indonesia that focuses on developing human resources in South Sumatra, facilitates local governments in developing employee capacity. This program was carried out for 5 days to learn about the basic level Geographic Information System (GIS) for Bappeda Lahat employees. This program is carried out in 3 stages, namely identification of partner problems, training, and evaluation. This training program has a positive impact on employees in Bappeda Lahat, namely being able to make location points for regional planning with SmartGPS, making spatial shapefile data and making thematic spatial maps according to the main tasks of the job fields of employee...
Dalam penelitian ini dilakukan pengkajian dinamika massa air Arus Lintas Indonesia (Arlindo) dala... more Dalam penelitian ini dilakukan pengkajian dinamika massa air Arus Lintas Indonesia (Arlindo) dalam kaitannya dengan sumber asli air yang dapat teridentifikasi masuk dari Samudra Pasifik ke perairan Indonesia Bagian Timur. Wilayah studi berada pada 12.5° LU – 2.5° LS dan 122,5° BT - 140° BT. Sumber data adalah World Ocean Database 2001 dari National Oceanography Data Center (NODC), http://www.nadc.noaa.gov/PC5/WODo1/pacif_o.html . Analisis dilakukan dengan menggunakan metode core layer dan analisis isopiknal sedangkan untuk mengolah dan menampilkan data digunakan software Ocean Data View mp versi 1.2, http://www.awi-bremerhaven.de/GEO/odv . Dari analisis yang dilakukan teridentifikasi bahwa sumber air Arlindo yang masuk ke Perairan Indonesia bagian timur melalui gerbang Arlindo memiliki karakteristik dari berbagai massa air, antara lain adalah core dari; NPSW dengan densitas potensial sekitar 24 s q salinitas 34.76 4 ml/l; SPSW dengan densitas potensial ekitar 25 s q salinitas S>3...
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