MODEL PEMBANGKIT DATA CURAH HUJAN: STUDI KASUS STASIUN SIMPANG ALAI KOTA PADANG

The effort on constructing weather data generator to cope with the scarcity of daily rainfall data is becoming essential recently. The objective of the paper is to generate rainfall daily data using stochastic spreadsheet. This technique can generate random values derived from the Gamma distribution which is initiated by the determination of rainfall probabilities, the occurrences on certain days and followed by the generation of rainfall height. The result showed that the rainfall data generator in Padang at period 1976-2005 showed consistent patterns with the observation eventhough simulation on day 180th the value is too high. Based on T-paired test, it showed no statistically significant different between simulation and observation (P-Value=0.000). Thus, the model can be employed as daily rainfall generator that can be further used to support the sustanaibility of agricultural activitiesin and food security in Padang. Key words: the scarcity, Gamma distribution, food securit

SIMULASI MODEL HBV PADA DAERAH ALIRAN SUNGAI BATANG ARAU PADANG

The objective of the study was to apply and to test the HBV subtropical model into a tropical region Batang Arau watershed Padang. Batang Arau watershed, located in Padang, covers an area of 106 km2. The HBV model was manually calibrated by trial adjustment of each parameter to obtain the appropriate physical characteristics of Batang Arau watershed. The study shows that the correlation coefficient of 0.48 and the value of NSE at 0.58. The value indicates the HBV modeling included in the category of accuracy being and indicated that HBV built models can not simulate the discharge of DAS Batang Arau quite well and can not be used to represent the real situation in DAS Batang Arau Padang. Although DAS Batang Padang Harau included in a small basin, but the model of HBV have not been able to describe the phenomenon that is properly due to the diversity of topography.Key words: Model HBV hydrology, watershed Batang Arau, the diversity of topograph

SYSTEMATIC LITERATURE REVIEW (SLR): NUCLEAR POWER PLANTS

Nuclear Power Plant (NPP) is a thermal power plant using one or several nuclear reactors as its heat source. NPP uses radioactive materials such as uranium as the heat source by utilizing fission reactions. The fission reaction produces enormous heat energy. Currently, there are many studies on NPPs, ranging from technological developments to the environmental impact of the NPP itself. This study aims to identify research developments on nuclear power plants from around the world obtained from relevant international journals in 2017-2023. The method used in this study is the Systematic Literature Review (SLR) method. The SLR method is used to identify, review, evaluate, and conclude all available research with interesting topic areas, with specific relevant research questions. Data were obtained by searching journals with Harzing's Publish or Perish application from the Scopus journal database. There are 191 journals with the keyword " Nuclear Power Plant " obtained from the Scopus database. Then these journals are filtered by type of article and if the number of citations is more than 32, then 49 articles are obtained which will be reviewed. This SLR method shows the development of research on NPP in several developed countries that have been using this technology for a long time. In addition, research topics such as the Fukushima accident, fault diagnostics, and safety assessment are the most discussed topics in the research so that they can be used as a reference for countries that are developing NPP

Climate Comfort in Nature-Based Tourism at Tropical Region

This research reveals visitor perceptions of climate comfort in nature-based tourism areas in Indonesia. We combined a survey and modeling to calculate the comfort score based on Tourism Climate Index (TCI) and Holiday Climate Index (HCI) in three tourism sites of Ecopark Ancol, Bogor Botanical Garden, and Cibodas Botanical Garden. During the survey, we collected data on climate comfort perceptions and the role of the weather on the comfort. Totally, 793 respondents of tourism visitors participated in the study. Our results showed that almost all of visitors (>95%) stated that the weather affected the climate comfort. Interestingly, the weather condition did not influence on the decisions where the tourism site to visit. The level of perceived climate comfort for the sites were neutral (Ecopark, 57.3%), and comfortable (Bogor Botanical Garden, 60%; Cibodas Botanical Garden, 78.4%). Then by modeling we obtained the best method to calculate the comfort based on the following index: (i) TCI with Physiological Equivalent Temperature (PET) Tianjin for Ecopark (57.2), (ii) HCI for Bogor Botanical Garden (59), and (iii) HCI with PET Tianjin for Cibodas Botanical Garden (77.6). Further, perception on climate comfort was significantly difference among sex, age, and education level of the visitors. In warmer environmental condition, the older people and women feel more comfortable. Our finding revealed that topography was weak correlated with comfort perception. By understanding visitor perceptions, strategies and appropriate actions can be developed to increase comfort in the nature-based tourism industry

Magnetic Susceptibility of Volcanic Soil on the Surface of Mount Singgalang, Sumatra Barat

Volcanic soil is a part of interest for physical, chemical, and morphology studies of soil derived from volcanic ash, which is known to be fertile and is one of the most productive soils in the world. They are also known to have a high environmental carrying capacity, as evidenced by the dense population in the area around the volcano. The soil contains many minerals, one of which is magnetic minerals. However, there is no document so far that records the value of the magnetic susceptibility of volcanic soil on the surface of Mount Singgalang. This study aims to determine the abundance of magnetic minerals based on their magnetic susceptibility values. To achieve this goal, the rock magnetism method is applied with the Bartington magnetic susceptibility meter type MS2B sensor instrument. Magnetic susceptibility values can be used as initial characteristics to understand past volcanic processes and explain environmental changes. This method is very effective, inexpensive, sensitive, fast, and non-destructive. The results showed that the value of the magnetic susceptibility of volcanic soils varied with a value range of 93.3 - 352.5 (x10−8 m3/kg). Based on this value, it is assumed that the magnetic mineral properties are antiferromagnetic. The average frequency dependent susceptibility (χfd) (%) ranges from 0.831 - 2.090 %, indicating that the measured volcanic soil contains almost no superparamagnetic grains and is generally dominated by multi-domain grains

ANALISIS PERIODE ULANG BANJIR DI KOTA PADANG MENGGUNAKAN CARA IWAI DAN KAITANNYA DENGAN MJO (MADDEN JULIAN OSCILLATION)

The research has conducted for the analysis of return period of flood over Padang using Iwai’s method. Iwai’s method is a statistical based method to look for a normal distribution. Daily rainfall data observed at seven stations observations were made over the period of analysis to figure out the pattern, then seen his relationship with the MJO. The results of the research obtained monthly rainfall distribution pattern over Padang show equatorial type that has two peaks of rainfall in a year are March and April as the first peak while the second peak in November. Return period rainfall for the 60 days over Padang is 88 mm and is 78 mm in 30 days. Incidence of flooding over Padang in 2000-2010 have a strong relationship with the entry of the MJO phases 3 and 4, is shown from the flood events of 2001, 2002, 2003, 2004, 2006, 2007 and 2009 with a rainfall intensity approaching the calculation of return period 30 - 60 days is 78-88 mm. Key words: Iwai’s Method, return period, floo

SIMULASI MODEL HBV PADA DAERAH ALIRAN SUNGAI BATANG ARAU PADANG

The objective of the study was to apply and to test the HBV subtropical model into a tropical region Batang Arau watershed Padang. Batang Arau watershed, located in Padang, covers an area of 106 km2. The HBV model was manually calibrated by trial adjustment of each parameter to obtain the appropriate physical characteristics of Batang Arau watershed. The study shows that the correlation coefficient of 0.48 and the value of NSE at 0.58. The value indicates the HBV modeling included in the category of accuracy being and indicated that HBV built models can not simulate the discharge of DAS Batang Arau quite well and can not be used to represent the real situation in DAS Batang Arau Padang. Although DAS Batang Padang Harau included in a small basin, but the model of HBV have not been able to describe the phenomenon that is properly due to the diversity of topography. Key words: Model HBV hydrology, watershed Batang Arau, the diversity of topograph

PEMODELAN INVERSI DATA GEOLISTRIK 1-D UNTUK MENENTUKAN JENIS DAN KEDALAMAN BATUAN DASAR

Large earthquakes that occurred in the city of Padang had been expected to lead to changes in the structure of rocks beneath the surface composition including bedrock. Information about the composition of these rocks can be obtained by conducting geological surveys by using geoelectric methods (resistivity). This method is very good to know the condition or subsurface geological structures based on variations in resistivity. Research is inversion modeling. Equation used is forward modeling of resistivity 1-D using Jacobi matrix element finite difference approach. The data used are secondary data obtained from a previous study by the Department of Physics geoelectric exploration team of UNP. Resistivity is determined from an apparent resistivity measurements. Types are resistivity investigation using Vertical Electrical Sounding (VES) or depth investigation, with distinction anisotropic cross section in the vertical direction. The data inversion modeling results resistivity 1-D using IPI2WIN software obtained bedrock on the track of FE to FIS at the point of sounding 2/7 at depths >  18.3 m  the resistivity is 1002 Wm, on track of UNP gate to FT at the point of sounding 2/7 at depths >  25.6 m the resistivity is 744   Wm and at the point of sounding 5/7 on the surface to a depth of 3.75 m the resistivity is  778  Wm and on track of Balai Bahasa to Al Azhar mosque at the point of sounding 7/7 at a depth of >  11.4 m the resistivity is 923 Wm. While on the track of FIK to Lab. Biology is not found bedrock. Bedrock types found are suspected Andesite which form the basis for the layer above it as Alluvium and Sands, Sandstones and Clays. Modeling results are not so good, as evidenced by the error (RMS error) more than 5%, which means the calculation data does not approach the observations data. This is due to the amount of noise during measurement that sourced from the equipment used and the environmental conditions such as there are many trees, electrical wires and the route is paved. Key words: resistivity method, modeling, inversion, VE

PEMODELAN INVERSI DATA GEOLISTRIK 1-D UNTUK MENENTUKAN JENIS DAN KEDALAMAN BATUAN DASAR

Large earthquakes that occurred in the city of Padang had been expected to lead to changes in the structure of rocks beneath the surface composition including bedrock. Information about the composition of these rocks can be obtained by conducting geological surveys by using geoelectric methods (resistivity). This method is very good to know the condition or subsurface geological structures based on variations in resistivity. Research is inversion modeling. Equation used is forward modeling of resistivity 1-D using Jacobi matrix element finite difference approach. The data used are secondary data obtained from a previous study by the Department of Physics geoelectric exploration team of UNP. Resistivity is determined from an apparent resistivity measurements. Types are resistivity investigation using Vertical Electrical Sounding (VES) or depth investigation, with distinction anisotropic cross section in the vertical direction. The data inversion modeling results resistivity 1-D using IPI2WIN software obtained bedrock on the track of FE to FIS at the point of sounding 2/7 at depths >  18.3 m  the resistivity is 1002 Wm, on track of UNP gate to FT at the point of sounding 2/7 at depths >  25.6 m the resistivity is 744   Wm and at the point of sounding 5/7 on the surface to a depth of 3.75 m the resistivity is  778  Wm and on track of Balai Bahasa to Al Azhar mosque at the point of sounding 7/7 at a depth of >  11.4 m the resistivity is 923 Wm. While on the track of FIK to Lab. Biology is not found bedrock. Bedrock types found are suspected Andesite which form the basis for the layer above it as Alluvium and Sands, Sandstones and Clays. Modeling results are not so good, as evidenced by the error (RMS error) more than 5%, which means the calculation data does not approach the observations data. This is due to the amount of noise during measurement that sourced from the equipment used and the environmental conditions such as there are many trees, electrical wires and the route is paved.Key words: resistivity method, modeling, inversion, VE

ANALISIS CURAH HUJAN KOTA PADANG SAAT MADDEN JULIAN OSCILLATION PERIODE 1980-2010

Madden Julian Oscillation (MJO) is a phenomenon that affects the activity patterns of convective clouds and rainfall, thus this study has the objective to analyze the characteristics of the MJO with increased rainfall due to convective activity over Padang. Daily rainfall data observed in seven observation stations analizing wavelet power spectrum to determine the pattern of rainfall in the region, further correlation it with the MJO. Important results obtained based on rainfall data is Padang has equatorial pattern. Correlation between the results obtained with the strong MJO rainfall is -0.54 to -0.687 in phase 3 and phase 4 is  -0.564 to -0.69 with a confidence level of 90% -95%. These results indicate that strong MJO events in phase 3 and 4 do not directly affect the increase in precipitation, due to the phase difference and the lag at seven observation stations over Padang. Physically, out of phase and lag means that any strong MJO enters Padang occurs cloud growth process and after the strong MJO exit this area then who have formed the clouds turned into rain. For the above normal category, excess rainfall while strong MJO phase 3 is the observation station Simpang Alai and Tabing respectively 122% and 120%, as well as strong MJO phase 4 is the observation station of Gunung Sariak, Kasang, Gunung Nago, Batu Busuk and Ladang Padi sequential 118%, 116%, 123%, 119% and 117%. Keywords: MJO, rainfall, wavelet