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Impacts of Extreme Weather on Sea Surface Temperature in the Western Waters of Sumatera and the Southern Waters of Java in June 2016
No full textOcean dynamics is affected by atmospheric conditions. Surface wind is one of atmospheric variables that has an important role in the ocean dynamics. This study was conducted to determine impacts of extreme weather on sea surface temperature in the western waters of Sumatera and the southern waters of Java in June 2016. Daily surface wind (2007-2016), sea surface temperature (1987-2016), sea wave height (1-10 June 2016) and surface current (1994-2016) were analyzed using anomaly analysis to assess the impact of surface winds on surface ocean. The result showed that in June 2016 extreme weather occurred in these waters that was characterized by sea wave height reached 2.6 m. Impacts of extreme weather in these waters cause upwelling intensity weakened that was marked by increase of sea surface temperature. The increases of sea surface temperature in the middle to north of western waters of Sumatera reached 0.9 OC, in the middle to south of western waters of Sumatera reached 1.8 OC and in the southern waters of Java reached 1.6 OC
The Relationship between the Mixed Pixel Spectral Value of Landsat 8 OLI Data and LAPAN Surveillance Aircraft (LSA) Aerial-Photo Data
Get PDFMedium resolution satellite data such as Landsat is very potential for mixed pixel (mixel) to occur. Indonesian land use diverse especially urban areas makes high potential mixel in the first Landsat pixel size of 30 meters x 30 meters on the actual condition. Aircraft multispectral aerial photo data LAPAN Surveillance Aircraft (LSA) with a spatial resolution reached 58 cm can display objects in more detail in these sizes. The purpose of this research is to study mixel on Landsat data with multispectral data LSA as a complement Landsat data. The method proposed in this study is a visual interpretation with GEOBIA method for classification of land cover, and then test the validity of the sample to be used in research, and the use of such vegetation index NDVI to see the connection between vegetation index data of vegetation index LSA with Landsat data. The results showed that the regression equation obtained by regression between NDVI of Landsat data and NDVI of LSA with a significance of less than 0.05 is y = 0.732x - 0102 with a value of R2 = 0.887. Through these results we can conclude that the NDVI values on both the data related to one another
Dynamic Land Resources Management at the Mount Kelud, Indonesia
Get PDFThere is a contradictive situation between the theory that believes that high volcanic hazard areas should be for limited production zones and those areas that are intensively utilised for several production activities. This paper tries to discuss that contradictive situation from both the perspective of natural hazards and natural resources, therefore, the best options for the land utilisation pattern might be formulated at these high volcanic hazards areas. We conducted landscape analysis that covers volcanic morphology, volcanic materials, and both natural and artificial processes that modify the morphology and materials characteristics. The natural processes occurring in the high volcanic hazard might cover non-volcanic processes such as erosion and landslide. The artificial processes were usually considered as land utilisation activities by the local community. In such areas where both natural and artificial processes occurred, we conducted in-depth interviews to assess the community perception on thread and benefits of the last Kelud Eruption in February 2014. We evaluated the current land resources utilisation and portrayed the local adaptive land resource utilisation. There were three types of land resources available at the active volcano: space, natural scenery, and volcanic materials. The availability of these land resources was in a dynamic condition both in terms of quality and quantity. Immediately after the eruption, the natural scenery made the area attractive as a tourist destination. Following the high intensity of rainfall, the volcanic materials might be used as high-quality construction materials. The available space might be utilised for any purposes after the situation became relatively stable. The current space was mostly used for agricultural enterprises which accommodates the physical and socio-cultural characteristics of the active volcano environment
Spatio-Temporal Distribution of Landslides in Java and the Triggering Factors
Get PDFJava Island, the most populated island of Indonesia, is prone to landslide disasters. Their occurrence and impact have increased mainly as the result of natural factors, aggravated by human imprint. This paper is intended to analyse: (1) the spatio-temporal variation of landslides in Java during short term and long-term periods, and (2) their causative factors such as rainfall, topography, geology, earthquakes, and land-use. The evaluation spatially and temporally of historical landslides and consequences were based on the landslide database covering the period of 1981 – 2007 in the GIS environment. Database showed that landslides distributed unevenly between West Java (67 %), Central Java (29 %) and East Java (4 %). Slope failures were most abundant on the very intensively weathered zone of old volcanic materials on slope angles of 30O – 40O. Rainfall threshold analysis showed that shallow landslides and deep-seated landslides were triggered by rainfall events of 300 – 600 mm and 600 mm respectively of antecedent rainfall during 30 consecutive days, and many cases showed that the landslides were not always initiated by intense rainfall during the landslide day. Human interference plays an important role in landslide occurrence through land conversion from natural forest to dryland agriculture which was the host of most of landslides in Java. These results and methods can be used as valuable information on the spatio-temporal characteristics of landslides in Java and their relationship with causative factors, thereby providing a sound basis for landslide investigation in more detail
Karakteristik Kualitas Air Limpasan di Daerah Urban Sebagai Sumber Pencemaran Air
Get PDFPerkembangan daerah kota dapat memberikan dampak negatif pada kondisi bidrologi, baik pada air permukaan maupun air tanah. Perkembangan daerah kota juga didukung oleh pertambangan sarana transportasi serta prasarananya, yaitu jalan raya dan kendaraan bermotor. Perkembangan daerab permukiman di daerah perkotaan juga menyebabkan bertambahnya volume limpasan dan penurunan kualitas air. Penelitian yang mengarah kepada dampak terbadap kondisi hidrologi, khususnya pada kualitas air di beberapa negara di luar Indonesia dikaji, khususnya yang menyangkut kualitas air permukaan yang berasal dari daerah kota. Zat kimia yang terdapat di dalam air sudah ada sejak awal terbentuknya tetesan air hujan dan pada proses jatuhnya air hujan ke muka bumi. Terdapatnya inti kondensasi sudah menunjukkan masuknya zat lain ke dalam air hujan. Pada saat hujan jatuh ke muka bumi, berbagai macam gas terlarut di dalam air hujan tersebut. Air hujan yang jatuh di muka bumi melarutkan tanah batuan dan material lain yang ada di muka bumi, selanjutnya zat yang larut tersebut terbawa aliran air yang terbentuk. Di daerah perkotaan material di tanah pekarangan dan jalan raya merupakan sumber pencemar yang sangat berarti. Beberapa penelitian menujukkan bahwa air limpasan yang berasal dari daerah perkotaan, baik yang berasal dari jalan raya maupun dari pekarangan mempunyai kadar zat kimia yang cukup tinggi dan mempunyai potensi yang cukup sebagai pencemar bagi badan air penerima limpasan tersebut. Pencemar tersebut dilihat dari BOD, COD, kadar zat tersuspensi, kadar zat terlarut, klorida posfat, nitrat dan bakteri bentuk coli. Bahkan ada beberapa kadar logam berat seperti Pb yang terdeteksi pada limpasan ini. Mengacu kepada basil penelitian di luar negeri nampaknya penelitian di Indonesia semacam itu perlu pula dilakukan, mengingat babwa perkembangan kota di Indonesia pesat juga
Yogya Utara=Bandung Utara? Dilema Tata Ruang Kawasan Resapan Air di DIY
Get PDFSecara umum pemanfaatan ruang dapat diklasifikasikan menjadi dua, yaitu sebagai kawasan budidaya (pertanian maupun non pertanian) dan kawasan non budidaya (lindung, daerah bahaya alam, dsb). Permasalahan yang muncul adalah sebaran kawasan-kawasan tersebut seringkali saling baur (campur), sehingga menambah rumit di dalam pengelolaannya, lebih-lebih pengelolaan dengan sistem pengendalian dan pengawasan yang belum jelas benar wewenangnya atau masih cenderung terlalu mudah untuk diintervensi oleh penguasa (tunggal) daerah dengan kebijakan "mudah diatur"
Slum, Development in Yogyakarta City 1970-2000
Get PDFSlum, a dwelling that is statutorily unfit for human habitation, is still the big problem in, especially, cities of developing countries. This article highlights the development of slums in Yogyakarta City along 1970-2000, and it’s merely focused on spatial and socio-ecological development. The aims of the study is to analyze the distribution and development process of slum dwellings. Distribution of slum area is taken from interpretation of time-series aerial photos. The change of extent and distribution of slum is analyzed using Geographic Information System. To obtain the socio-economic characteristics of slum dwellers, the survey method is chosen. The respondent are selected randomly among head of household that represent each settlement units. Quality of settlement are determined by total score of 15 selected variables. The result shows that the first category of slum was increased 74.4 hectares from year 1970 to 2000, the second category was increased 47.6 hectares, and the third was 131.1 hectares. Nevertheless, the process of slum development in Yogyakarta City includes in "continuous" type, which slowly and long period of creation. Densification and aging process is two of the main causes of slum expansion. Distribution of slum unit were driven by rivers that next to city center. According to this research, it’s found out that the slum dwellers are characterized by the new migrant who had low income and education, working in the informal sector, and renting the house
Charasteristics of Ageing Population in Semarang City
No full textIncrease of amount of ageing population represent the indication that a region have experienced of the ageing population. In some developing countries, of including Indonesia, growth of ageing population are estimate will mount quickly in period to come, although its percentage do not same. Whereas characteristic do not know surely. This matter is caused by there is view that ageing population of still not yet of this problem, but within long term will be are problem of if are not paid attention since now. Studying of ageing population of pursuant to its characteristic will assist in handling good problems now and also to come. With the existence of data of usable ageing population resident characteristic for the materials of population development planning in area
Influence of Geographical Conditions on the Spatial Structure of Jayapura City
No full textJayapura City is situated in the eastern tip of Indonesia and borders the neighboring country Papua New Guinea (PNG). Its geographical conditions are very diverse dominated by hills leading to the formation of separated urban areas. Currently, there are two major urban areas, Jayapura and Abepura. Historically, Jayapura and Abepura were two old towns established in the Dutch rule, namely Hollandia Haven and Hollandia Binnen. They are detached by Skyline hills that hinder their complete physical merger. The presence of two separated urban areas in Jayapura City is also reinforced by the image perceived by the residents regarding with the powerful visual image of those cities. It however forms unique and distinctive properties in the spatial structure of Jayapura City. This study examines how the influence of geographical conditions on the spatial structre of Jayapura City. Data collection was done through direct observation and interviews with respondents of Jayapura and Abepura. Direct observation was conducted to obtain data on the use of land that form patterns in Jayapura City area. While collecting data through questionnaires conducted to determine the image of residents of Jayapura City on the spatial structure of the city. The results showed that the geographical conditions in Jayapura City affect the formation of two separate parts of the city. The geographical condition is also an element forming a strong spatial structure as a characteristic reinforces the visual impression of the existence of two cities in a “single city”
Pemanfaatan Data Iklim untuk Evaluasi Kekeringan dengan Menggunakan Indeks Palmer
Get PDFTujuan penelitian ini ialah mengevaluasi tingkat kekeringan di daerah Kedu Selatan, Jawa Tengah dengan menggunakan Indeks Palmer, dengan harapan agar dapat diperoleh gambaran hubungan antara curah hujan dan indeks kekeringan. Data yang digunakan adalah curah hujan dan suhu udara rataan bulanan selama 5 tahun (antara 1972 dan 1976) dan air tanah yang tersedia pada kedua lapisan tanah atas. Data hujan diambil dari 69 stasiun penakar hujan biasa. Data klimatologi diperoleh dari stasiun Sempor dan basil akhir berupa Peta Indeks kekeringan. Hasil perhitungan indeks kekeringan atas data hujan di suatu lokasi menimbulkan indeks yang terlalu basah atau terlalu kering dari keadaan normalnya untuk di suatu tempat. Hubungan dua deret waktu antara hujan dan indeks kekeringan menunjukkan bahwa daerah yang berhutan dengan kondisi tanahnya berupa tanah liat, timbulnya kekeringan mengalami kemunduran setelah beberapa bulan tidak terjadi hujan. Sebagian besar-koefisien korelasi (r) menunjukkan nilai yang lebih besar daripada koefisien korelasi-lag (rL), kecuali di daerah yang mempunyai kawasan hutan cukup luas. Kelayakan Peta Indeks kekeringan dapat dikaitkan dengan penuruan produksi pertanian (padi ladang) dan peristiwa banjir yang pernah terjadi di daerah penelitian