Jurnal Meteorologi Klimatologi dan Geofisika

EVALUATING METEOROLOGICAL DATA FOR NUCLEAR POWER PLANT (NPP) PUSPIPTEK SERPONG

2021-03-18T11:17:32+00:00

Precise and consistent meteorological data is needed to support safety and security as well as in an effort to meet safety requirements and criteria from the initial stages of siting, design, construction, even activities in the previous stages to the operation stage, handling safety during and during decommissioning and waste management radioactive. Therefore, the aim of this study is to identify and analyze the distribution of data distribution to see the extent to which meteorological data for nuclear site area provide accurate and precise data so that it can be used scientifically. In the present paper, the concentrations calculated by this method are compared with data observed over Portable Weather Station (PWS) and existing Automatic Weather Stations (AWS). Good agreement was confirmed in similar data observed and existing of PWS or AWS data due to statistically calculating test using correlation, deviation and Root Mean Square Error (RMSE). The two AWS tested, both Experimental Power Reactor (RDE) and Nuclear Serpong Area (KNS), gave fairly good scores statistically. Analysis on October 13, 2020, the value of RMSE, and the correlation between AWS RDE and KNS, respectively, is 361.2; 67.6 and 0.56. Then the data analysis on October 14, 2019 which compared AWS RDE and PWS, the value of Standard Deviation, RMSE, and the correlation between AWS RDE and PWS were 137.3; 8.65 and 0.48. The availability of good data is 98.3% for RDE and 95.3% for KNS, respectively.

PEMETAAN PERKIRAAN POTENSI GELOMBANG LAUT SEBAGAI PEMBANGKIT LISTRIK TENAGA GELOMBANG LAUT DENGAN SISTEM PELAMIS DI PERAIRAN NIAS

2021-03-18T11:17:37+00:00

The need for electricity using alternative energy is very necessary to replace fossil energy, notably coal power plant sector which is very polluting the environment, the development of alternative energy also supports the realization of sustainable development goals (SDGs) in providing clean and renewable energy. Indonesia has great potential in developing ocean wave energy of around 41 gigawatts, so that it can help to fullfil national electricity consumption. The purpose of this study is to determine the ocean wave potential using conversion of power density of Pelamis (Sea Dragon) electricity analysis in Nias Waters, North Sumatera. This study uses quantitive-case method. This study uses surface wind data from ERA5 and ASCAT in 2019; by processing wind data to generate wind roses using WRPlot software, SMB (Sverdrup-Munk-Bretschneider) method to determine wave forecasting and wave equation using IDL programming, as well as the wave energy density equation using mass-Damper-system electrical energy conversion in the Pelamis module. Based on the study, the results of significant wave height and periode are obtained 0.63 meters and 4.05 seconds, with the conversion angle between the Pelamis arms module is 46,85^o using Damper spring between 1.00-1.73 meters, with average of ocean wave density is 82,01 kW/m²; maximum kW/m²; minimum 17,32 kW/m².

PENGARUH KETERSEDIAAN RUANG TERBUKA HIJAU TERHADAP TINGKAT KENYAMANAN TERMAL DI WILAYAH PERKOTAAN (Studi Kasus di Kelurahan Sokanegara, Kota Purwokerto)

2021-03-18T11:17:48+00:00

Population increasing in the city of Purwokerto affects the increase in built-up area and reduced vegetation areas or Green Open Space (RTH). According to the Ministry of Public Works, urban areas must provide green open space (RTH) as much as 30% of the total area. The condition of Green Open Space (RTH) and its availability is important for a city because it will greatly affect the environmental conditions and microclimate around the area. This study aims to determine the availability of Green Open Space (RTH) in urban areas and its effect on the level of thermal comfort by emphasizing the Sokanegara, Purwokerto City. The data used is the Sentinel-2A satellite image data acquisition of 12 September 2019, for analysis of the distribution of green open spaces using the NDVI (Normalized Difference Vegetation Index) algorithm. The method to get the level of thermal comfort is to use the THI (Thermal Humidity Index) index. The results indicated that all types of green open space in Sokanegara sub-district categorized as uncomfortable because the THI value at each sample point of green open space is more than 28 ℃. Therefore, further planning is needed to increase the Green Open Space in Sokanegara Village, East Purwokerto.

NORMAL STANDAR KLIMATOLOGI UNTUK PEMETAAN POTENSI ENERGI ANGIN DAN SIMULASINYA DI WILAYAH KALIMANTAN BARAT

2021-03-18T11:17:58+00:00

Today, there are more and varied researches on renewable energy, including on utilization of wind energy. Wind energy has been used to generate 147 MW of electricity in Sidrap and Jeneponto (South Sulawesi). The present study is prepared to determine the amount of wind energy potential and its capability in the power produced in West Kalimantan. The study was performed using statistic calculation and analysis by using data of wind speed at an altitude of 10 meters above ground level from manual observation and PSD reanalysis, NOAA. The research result shows that wind energy potential is relatively low in June and December, as shown in the map of wind energy potential based on climatological standard normal. Following shear pattern on streamline, central West Kalimantan has the lowest wind energy potential (< 25 W/m²). The highest wind energy potential is in Ketapang Regency (Tumbang Titi Sub-district) which is > 52 W/m²). HOMER simulation for Tumbang Titi shows wind energy potential can be used to generate into 9,457 kWh/year and requires $4,071.15, with most of the expenses for wind turbine which amounts to $3,632.61.

KAJIAN KECEPATAN TRANSFER GAS KARBONDIOKSIDA (CO2) SAAT SIKLON TROPIS DI LAUT SELATAN JAWA SECARA KLIMATOLOGI PADA BULAN MARET, APRIL, MEI TAHUN 2008 HINGGA 2020

2021-03-18T11:18:07+00:00

Tropical cyclones can move huge amounts of heat energy from oceans into atmosphere. The transfer of heat between oceans and atmospheres is related to the transfer of CO₂ gas from oceans to atmospheres. Tropical cyclones affect the absorption of CO₂ into atmosphere, where wind speed and sea surface temperatures play a role in the release of CO₂ into atmosphere. The study examined how tropical cyclones affect the transfer of CO₂ gas from oceans to atmosphere in the Southern sea of Java in the transition season 1, which is March, April, and May starting from 2008 to 2020. The method used in the form of analysis of atmospheric and ocean dynamics uses data components of wind speed direction u and v at altitude of 10 meters as well as sea surface temperature data. The data was obtained from the ERA5 reanalysis model which is the fifth generation of ECMWF. The maximum speed of monthly CO₂ transfer in March was 150 m/s, in April at 122.3 m/s, and in May at 122.3 m/s. The climatology results show that the speed of CO₂transfer is maximum when a tropical cyclone occurs in March and at least in tropical cyclones that occur in May.

ANALISI HUBUNGAN MAGNITUDO GEMPA BUMI TERHADAP HASIL FREKUENSI DOMINAN PADA RANGKAIAN GEMPA ACEH 2004, YOGYAKARTA 2006, PALU DAN LOMBOK 2018 SEBAGAI UPAYA MITIGASI BENCANA

2021-03-18T11:18:16+00:00

Indonesia is located at the boundaries of three major plate of the world, namely Indo-Australia, Eurasia, and the Pacific Plates. This has made Indonesia prone to earthquakes, so mitigation are needed. The purpose of this research is to determine the empirical relationship between earthquake magnitude and dominant frequency results based on several major earthquake events in Indonesia such as in Aceh 2004, Yogyakarta 2006, Lombok and Palu 2018 as an effort to earthquake hazard mitigation in Indonesia. Magnitude carries information about earthquake power based on the energy released from the hypocenter. Physically, magnitude is related to frequency. The frequency can obtained from earthquake records in time domain which are converted to frequency domain by Fast Fourier Transform method. Earthquake data is obtained from IRIS and uses 89 events with magnitude of 4-9. In Aceh, Yogyakarta, Lombok, and Palu that relatioship between magnitude and frequency are y = -0.053x + 6.2999, y = 0.018x + 4.082, y = -0.0496x + 6.455, and y = -0.0192x + 5.3129. In this research, it can be concluded that the bigger magnitude of the earthquake has smaller frequency. The potential magnitude that appear if the seismicity are low in Aceh, Yogyakarta, Lombok, and Palu are 6.2, 4, 6.4, and 5.3.

ANALISIS TINGKAT RISIKO DAN KERENTANAN BAHAYA GEMPA BUMI DI KOTA SURABAYA DALAM UPAYA PEMBERIAN INFORMASI MITIGASI BENCANA

2021-03-18T11:18:24+00:00

Surabaya segment and Waru segment, part of Baribis-Kendeng Fold Thrust Zone that passes through Surabaya City potentially affected by earthquake hazard in the future with high population that settled there and high number of buildings. The impact of earthquake hazard can be decreased by Peak Ground Acceleration (PGA), high population density, and buildings analysis as an action of mitigation. PGA value calculated by McGuire empirical formula (1974, 1977) using historical data of earthquake in the past 50 years and the result of this value among 33,991 -29,8194 gal, this result classified as low frequency related to MMI scale that released by BMKG. The map result of PGA that related to spatial data of high population and high buildings in the Surabaya conclude that east side of Surabaya has a very high risk of earthquake vulnerability.

PERUBAHAN LAMA PENYINARAN MATAHARI TAHUN 1990-2019 DI KALIMANTAN BARAT

2021-03-18T11:18:30+00:00

The sun is a source of renewable energy relating to climate change. Sunshine Duration (SD) is the element to an important indicator of the sun. West Kalimantan is located in the equator area receiving sunlight most of the year. This study aims to identify change in SD in West Kalimantan. The variable used is the average SD data from 1990 to 2019 divided into three time periods at five stations representing monsoon and equatorial rain patterns in West Kalimantan. ANOVA and Tukey tests are used for statistical analysis. The highest average SD is at Ketapang Station. The average annual SD in the monsoon region is higher than the equatorial region. In the dry season, the average monthly SD is higher than during the rainy season. There was an anomaly SD in the dry season in 1997 due to forest and land fires which corresponds to the El Nino event. The time period of the decade has a real effect on the average annual SD at Sambas and Supadio Pontianak Station. The average SD in 2010-2019 at Sambas Station and Supadio Pontianak Station was higher than the previous year's period. SD is an important factor for measuring solar energy, so the change shows good availability as a renewable energy source in West Kalimantan.