bluuebunny/crossref_metadata_2025 huggingface dataset:
Meridional Migration of Diurnal Heavy Rainfall during Extreme Events over Java and Surrounding Waters and Its Relation to Madden Julian Oscillation
Authors: Rais A. F. , Kosasih A. , Sujarwo  , Fitrianto M. A. , Kamid A. , Surgiansyah P.
Published: December 2021

In this study, meridional migration characteristic of diurnal heavy rainfall (DHR) over Java and surrounding waters and its relation to Madden Julian Oscillation (MJO) during extreme events was investigated. The rainfall data was the Climate Prediction Centre Morphing (CMORPH) V1.0 in the December-January-February (DJF) wet season of the 1998-2019 period. The thresholds of extreme events were based on the 95% percentile of daily rainfall area average of mountainous area (MA), northern plain area (NPA), northern waters (NW), southern plain area (SPA), and southern waters (SW) that were based on Global Land One-kilometer Base Elevation (GLOBE) Digital Elevation Model. We analyzed meridional migration of DHR through composite and the Hovmoller diagram. To get the MJO signal, we used the Wheeler-Kiladis wavenumber-frequency domain to filter outgoing longwave radiation (OLR). The results showed that DHR was stationary over the mountains, migrated to the Java Sea (The Indian Ocean), and was stationary over the Java Sea (Indian Ocean) in conjuction with migration from Java to the waters when extreme events occur over MA, NPA (SPA), and NW (SW), respectively. Based on a comparison of MJO-OLR during extreme events period of MA, NPA, SPA, NW, and SW, it seems that MJO had a stronger impact on the DHR of NW and SW than the others, but it must be examined based on significant test in the further study.
Utilization of Red-Green-Blue (RGB) modification composite for nighttime convective cloud monitoring over North Sumatra region
Authors: Saragih I J A , Tarigan K , Sinambela M , Situmorang M , Sembiring K , Humaidi S , Sirait M
Published: December 2021

Located between the Indian Ocean and the Malacca Strait, also the presence of the Bukit Barisan Mountains cause high convective activity in the North Sumatra region. The Himawari-8 satellite has 16 atmospheric observation channels that allow for observations of the convective system growth phase. The Red-Green-Blue (RGB) composite method is used to display a variety of satellite image composite information. The nocturnal convective system that often forms in the coastal areas of Sumatra causes heavy rains. A nocturnal convective system observation method is needed to publish early warning information on extreme weather. This research was conducted to observe the nocturnal convective system during heavy rain events in the North Sumatra region using a modification of RGB composite. This research used the Himawari-8 satellite data, Coloumn Max (CMAX) products of Medan weather radar data, and Global Satellite Mapping of Precipitation (GSMaP) rainfall estimation data. Comparison of RGB modified products with Night Microphysics RGB products and CMAX weather radar products, as well as time-series rainfall analysis. The results showed that the RGB modification product could capture the beginning of the convective system's growth, development, and spatial movement. The convective cloud distribution pattern corresponds to the area of heavy rain. There is a slight difference in cloud growth area between the satellite and radar products indicated the parallax error from the satellite image.
Estimation of Probable Maximum Precipitation (PMP) and Probable Maximum Flood (PMF) Using GSSHA Model (Case Study Area Upper Citarum Watershed)
Authors: Sibuea Puji R A , Agriamah Dewi R , Riawan Edi , Suwarman Rusmawan , Lubis Atika
Published: December 2021

Probable Maximum Flood (PMF) used in the design of hydrological structures reliabilities and safety which its value is obtained from the Probable Maximum Precipitation (PMP). The objectives of this study are to estimate PMP and PMF value in Upper Citarum Watershed and understand the impact from different PMP value to PMF value with two scenarios those are Scenario A and B. Scenario A will calculate the PMP value from each Global Satellite Mapping of Precipitation (GSMaP) rainfall data grid and Scenario B calculate the PMP value from the mean area rainfall. PMP value will be obtained by the statistical Hershfield method, and the PMF will be obtained by employed the PMP value as the input data in Gridded Surface Subsurface Hydrologic Analysis (GSSHA) hydrologic model. Model simulation results for PMF hydrographs from both scenarios show that spatial distribution of rainfall in the Upper Citarum watershed will affect the calculated discharge and whether Scenario A or B can be applied in the study area for PMP duration equal or higher than 72 hours. PMF peak discharge for Scenario A is averagely 13,12% larger than Scenario B.
Examining optimum prediction time of rainfall dynamics based on chaotic perspective at different temporal scales: a case study in Bojonegoro, Indonesia
Authors: Hidayat A M , Efendi U , Virgianto R H , Nugroho H A
Published: December 2021

As the driving force of the hydrological system, rain has severe impact when dealing with petroleum mining activities, especially in protecting assets and safety. Rainfall has high variability, both spatial and temporal (chaotic data). Due to this reason, ones can only create long-range prediction using the stochastic method. Here we use the Lyapunov exponent to analyze the nonlinear pattern of rainfall dynamics. This method is useful for identifying chaotic deportment in rainfall data. This study uses rainfall data for six years obtained from one of the largest petroleum mining sites in Bojonegoro, Indonesia. Rainfall dynamics have been analyzed on three different time scales, namely daily data, 5-day, and 10-day. The time delay (τ) was obtained by using the Average Mutual Information (AMI) method for the three-rainfall series (3, 2, 3, respectively). The observed rainfall data in Bojonegoro show signs of chaos as the finite correlation dimensions (m) attain values about 4 for all time scales. The maximum Lyapunov exponentλmaxfor each of three-rainfall series in Bojonegoro is 0.111, 0.057, 0.062, respectively. These values were analyzed to find the optimum prediction time of rainfall occurrence to perform better forecasting. The result shows that the optimum range of prediction time for daily, 5-day, and 10-day have 9, 18, and 16 times longer than their temporal scale.
Monthly daily-mean rainfall forecast over Indonesia using machine learning and artificial intelligence ensemble
Authors: Harsa H , Habibie M N , Praja A S , Rahayu S P , Hutapea T D , Swarinoto Y , Kurniawan R , Noviati S
Published: December 2021

A daily mean rainfall in a month forecast method is presented in this paper. The method provides spatial forecast over Indonesia and employs ensemble of Machine Learning and Artificial Intelligence algorithms as its forecast models. Each spatial grid in the forecast output is processed as an individual dataset. Therefore, each location in the forecast output has different stacked ensemble models as well as their model parameter settings. Furthermore, the best ensemble model is chosen for each spatial grid. The input dataset of the model consists of eight climate data (i.e., East and West Dipole Mode Index, Outgoing Longwave Radiation, Southern Oscillation Index, and Nino 1.2, 3, 4, 3.4) and monthly rainfall reanalysis data, ranging from January 1982 until December 2019. There are four assessment procedures performed on the models: daily mean rainfall establishment as a response function of climate patterns, and one-up to three-month lead forecast. The results show that, based on their performance, these non-Physical models are considerable to complement the existing forecast models.
Four-dimensional variational (4DVAR) performance test with assimilation satellite and radar data (case study of a heavy rainfall Bengkulu March 4, 2019)
Authors: Syafitri J D I , Sari F P
Published: December 2021

Four-dimensional variational (4DVAR) is one of the assimilation techniques considering time integration to distribute observational data at time window intervals. In this study, we aim to evaluate the 4DVAR assimilation technique using satellite and radar data to simulate a heavy rainfall case in Bengkulu on March 4, 2019. The result shows that radar data assimilation (DA-RAD) can improve rainfall pattern over Bengkulu mainland areas, while the satellite data assimilation (DA-SAT) enhances rainfall over the ocean. In addition, for temporal analysis, the DA-RAD successfully correct the initial time of the event, producing the smallest error and the best correlation in statistical verification, also a small bias and higher accuracy for discrete verification. However, DA-SAT is more capable to improve rainfall accumulation with the lowest FAR value. In conclusion, compared to others, both satellite and radar can be used as assimilation data for 4DVAR methods as they have different roles in increasing the quality of model performance.
The impact of land cover changes on temperature parameters in new capital of Indonesia (IKN)
Authors: Denryanto R A F , Virgianto R H
Published: December 2021

North Penajam Paser Regency and Kutai Kartanegara Regency which are located in East Kalimantan Province are two locations that are planned as the New Capital of Indonesia (IKN). This has become one of the factors changing land cover from vegetation land to urban land, so that it can contribute to temperature changes. In this work, we analyze impacts of land use change on temperature in the new capital city. The change will simulate land cover changes using the Weather Research and Forecasting (WRF) model with two scenarios of land cover change from vegetation land to 547 % and 1,222 % urban land. Scenarios I and II will increase the temperature to 1.17 and 1.77 °C, respectively. This could means that the addition of more urban areas results in an increase in temperature. The quantitative values of this connection will be beneficial for urban planners to manage the development of new capitals without having a significant impact on climate change.
Spatial fraction verification of high resolution model
Authors: Made Kembar Tirtanegara I , Sari Fitria Puspita
Published: December 2021

Fraction Skill Score (FSS) is one of spatial verification method to evaluate model performance on spatial scale variations. The method was applied to assess the Weather Research and Forecasting (WRF) model using 2 km (MODEL2KM) and 6 km (MODEL6KM) grid size. Cloud Top Temperature (CTT) data from Himawari-8 satellite was utilised as a ground truth data. This study aims to evaluate the model performance by FSS with absolute and percentile treshold on convective cloud simulation for three heavy rain events. The threshold considers the evaluation of absolute and percentile aspect. The result shows that there is no significant change in the FSS value for resolution increase of MODEL2KM compared to MODEL6KM. Also, the events of heavy rain having a lower CTT generate a higher FSS value for absolute threshold. Whilst, the percentile threshold for three cases have a greater FSS value, though it cannot provide the information of CTT absolute temperature value.
Utilization of ECMWF Seasonal Rainfall Forecast System (SEAS5) for forest fire prediction over Sumatera Island, Indonesia
Authors: Alfahmi F , Khaerima A , Byantoro A W
Published: December 2021

As part of the lungs of the world, the forest which covers Sumatra Island has a significant impact on the world oxygen production and the absorption of carbon dioxide. Drought over Sumatra Island often causes forest fires that can damage the function of forests as the world's lungs. Prediction of the seasonality of forest fires is needed to prevent and overcome forest fires that will occur next month. This study utilized seasonal rainfall predictions to predict the incidence of forest fires based on the drought index obtained. The result showed that ECMWF SEAS5 had good performance to predict rainfall over Sumatera Island for the first until the fourth months (lead time of 0 - 3). The Negative Standardized Precipitation Index (SPI) coincided with the increasing number of the hotspots. Furthermore, a linear equation has been applied to the calculated number of hotspots based on SPI from ECMWF.
The skill assessment of ENSO prediction issued by JMA ensemble prediction system and CFSv2
Authors: Rahmat R , Setiawan A M , Supari
Published: December 2021

Indonesian climate is strongly affected by El Niño-Southern Oscillation (ENSO) as one of climate-driven factor. ENSO prediction during the upcoming months or year is crucial for the government in order to design the further strategic policy. Besides producing its own ENSO prediction, BMKG also regularly releases the status and ENSO prediction collected from other climate centers, such as Japan Meteorological Agency (JMA) and National Oceanic and Atmospheric Administration (NOAA). However, the skill of these products is not well known yet. The aim of this study is to conduct a simple assessment on the skill of JMA Ensemble Prediction System (EPS) and NOAA Climate Forecast System version 2 (CFSv2) ENSO prediction using World Meteorological Organization (WMO) Standard Verification System for Long Range Forecast (SVS-LRF) method. Both ENSO prediction results also compared each other using Student's t-test. The ENSO predictions data were obtained from the ENSO JMA and ENSO NCEP forecast archive files, while observed Nino 3.4 were calculated from Centennial in situ Observation-Based Estimates (COBE) Sea Surface Temperature Anomaly (SSTA). Both ENSO prediction issued by JMA and NCEP has a good skill on 1 to 3 months lead time, indicated by high correlation coefficient and positive value of Mean Square Skill Score (MSSS). However, the skill of both skills significantly reduced for May-August target month. Further careful interpretation is needed for ENSO prediction issued on this mentioned period.
Automatic Rain Detection System Based on Digital Images of CCTV Cameras Using Convolutional Neural Network Method
Authors: Hakim Arif Luqman , Dewi Ristiana
Published: December 2021

The Meteorology, Climatology and Geophysics Agency (BMKG) has a duty to provide weather information including rainfall. BMKG has several types of rainfall gauges, but these are not evenly distributed across regions. The solution to increase the density of rainfall observations is to use existing sources to obtain weather information. This research uses Closed Circuit Television (CCTV) that is spread across the Jakarta area to produce information on rainy conditions. The method used is the Convolutional Neural Network (CNN). The image from CCTV will be used for the training and testing process, so as to get the best accuracy model. The results of this model will be used for rain detection on CCTV digital images. The rain detection process is carried out automatically and in real time. The results of the rain detection process will be displayed on the map according to the location where the CCTV was installed. This research has succeeded in making a CNN model for rain detection with a training accuracy of 98.8% and a testing accuracy of 96.4%, as well as evaluating the BMKG observation data, so it has an evaluation accuracy of 96.7%.
Why was the sky red in Jambi during the forest fire?
Authors: Kusumaningtyas S D A , Aldrian E , Suradi  , Ahmad M , Krisnawan G D
Published: December 2021

Extreme biomass burning occurred in Jambi, Indonesia, in 2019 and coincided exacerbated with El Nino. Peak burning season was in September, with a total hotspot of 7034. Red sky has been reported on September 21 during the day. Sun photometer measurements in Jambi as one of the Aerosol Robotic Network (AERONET) stations in Indonesia from 1 to September 26, 2019, were used to investigate the red sky phenomenon. Assessment of aerosol optical properties and spectral variation analysis is conducted. The study reveals that the red sky occurred due to, firstly, very high aerosol loading with fine size particles were present. The aerosol optical depth (AOD) was 0.34 at 500 nm on a non-hazy day (early September) and increased sharply to 5.74 during a hazy day. A high level of fine-mode particle was indicated with Angstrom Exponent>1. Secondly, during September 23, only longer wavelengths of AOD were measured at 675, 870, 1020, and 1640 nm, while AOD in shorter wavelengths cannot be retrieved. Highest AOD on September 23 was 6.19 at 675 nm, which is associated with the red sky in the previous day. Thirdly, SSA was near 1, indicating purely aerosol scattering due to coagulated fine-mode particles due to high humidity.
Measurement and Analysis of Ocean Current using High- Frequency (HF) Radar Observation in the Bali Strait
Authors: Firdaus R , Siadari E L , Alfahmi F
Published: December 2021

High-Frequency (HF) Radar is an instrument using radio waves to measure ocean currents and waves remotely. This technology has many advantages, including has unprecedented spatial and temporal resolution, can operate in any weather condition, and is not dangerous for the environment. However, HF Radar's research is still limited in Indonesia. This research aimed to analyze the tidal and residual current in the Bali Strait in July 2020. Radial velocity from two HF Radar sites is combined to obtain the total currents. Current data from HF Radar were compared with Acoustic Doppler Current Profiler (ADCP) data to investigate its accuracy. Surface current data were analyzed using harmonic analysis to separate tidal and residual currents. Comparison between HF Radar and ADCP data are in good agreement for meridional current with a very high correlation of 0.813 and a small RMSE value of 0.22 m/s. Harmonic analysis shows that the dominant currents are tidal currents. The current direction was northward (southward) at flood (ebb), with maximum northward (southward) velocities are 2.17 m/s (2.97 m/s), respectively. The residual current has a random pattern, slightly faster northward than southward, and has similar spectral with the wind.
Application of Attenuation Correction to Quantitative Precipitation Estimation on C-Band Weather Radar in Bengkulu
Authors: Handoyo M F , Hadi M P , Suprayogi S
Published: December 2021

A weather radar is an active system remote sensing tool that observes precipitation indirectly. Weather radar has an advantage in estimating precipitation because it has a high spatial resolution (up to 0.5 km). Reflectivity generated by weather radar still has signal interference caused by attenuation factors. Attenuation causes the Quantitative Precipitation Estimation (QPE) by the C-band weather radar to underestimate. Therefore attenuation correction on C-band weather radar is needed to eliminate precipitation estimation errors. This study aims to apply attenuation correction to determine Quantitative Precipitation Estimation (QPE) on the c-band weather radar in Bengkulu in December 2018. Gate-by-gate method attenuation correction with Kraemer approach has applied to c-band weather radar data from the Indonesian Agency for Meteorology and Geophysics (BMKG) weather radar network Bengkulu. This method uses reflectivity as the only input. Quantitative Precipitation Estimation (QPE) has obtained by comparing weather radar-based rain estimates to 10 observation rain gauges over a month with the Z-R relation equation. Root Mean Square Error (RMSE) is used to calculate the estimation error. Weather radar data are processed using Python-based libraries Wradlib and ArcGIS 10.5. As a result, the calculation between the weather radar estimate precipitation and the observed rainfall obtained equation Z=2,65R1,3. The attenuation correction process with Kreamer's approach on the c-band weather radar has reduced error in the Qualitative Precipitation Estimation (QPE). Corrected precipitation has a smaller error value (r = 0.88; RMSE = 8.38) than the uncorrected precipitation (r = 0.83; RMSE = 11.70).
Investigating consequences of choosing IDW interpolation parameters in East Java using raster analyses
Authors: Kurniawan A , Ryan M , Rafi A M , Haq B E A , Sudirman  , Suprayitno A
Published: December 2021

An observation network will never be enough for creating good information about monthly rainfall. An interpolation method is always needed. For operational purposes, inverse distance weighting (IDW) method is used. In East Java, 197 observation points are involved, then IDW's parameters used are neighbor=12 and power=2. The consequences of this framework are investigated in this study. By reversing IDW's formula, two kinds of raster analyses are developed, distance to neighbor used (DNU) and coefficient from point (CFP). DNU shows how far points are used for doing interpolation in some area by kilometer (km) meanwhile CFP describes an area impacted by a point and value sent to another cell from an observation point. Data used in this study are longitude and latitude of 197 observation points. The scripts are written in R Language. Analysis based on local governmental region shows that Sumenep has very far DNU. In average, the first point used located more than 25 km, and its twelfth is 112 km (average other regions DNU1=7 km and DNU12=35 km). It means there should be a unique interpolation mechanism for Sumenep. CFP confirms that some points give impact in unnatural ways (impacted area=5741 km2). We propose DNU and CFP as alternative quality control parameters for investigating consequences in interpolating rainfall.
Characteristics of Sea Surface Current in the Bali Strait, Indonesia using HF Radar and Its Utilization in Safety Navigation
Authors: Supriyadi E , Hidayat R , Santikayasa IP , Ramdhani A
Published: December 2021

This paper was done by using the HF Radar data from 2018-2019 to study the characteristics of Sea Surface Current (SSC) in the Bali Strait. The data processing method was done by calculating the speed and SSC direction of the zonal and meridional components. Furthermore, SSC analysis was performed every hour and month by calculating the average of all data at the same hour and month. It was found that the unique SSC pattern in the Bali Strait occurred on the western side of Bali Island and the eastern side of Java Island. On the west side of the Bali Island, there was a decrease in SSC speed at 0.00-7.00 and 13.00-18.00, as well as a two-fold increase at 8.00-12.00 and 19.00-2.00, both of which were in a fluctuating speed range from 0-140 cm s-1 in the direction of dominant towards the south. On the eastern side of Java Island, SSC speed ranges from 0 to 40 cm s-1 all the time with the dominant direction heading from east to southeast. The monthly SSC pattern was also seen more clearly in this study, meanwhile during December-March the SSC rate was lower than during June-September, ranging from 0 to 20 cm s-1 and from 40 to 140 cm s-1, respectively. Furthermore, the two SSC patterns above can be simplified into two periods, namely periods of relaxation and agitation. This study also applies the device to ship accidents that occurred in the Bali Strait as case studies.
Utilization of remote sensing data for mapping the effect of Indian Ocean Dipole (IOD) and El Nino Southern Oscillation (ENSO) in Sumatra Island
Authors: Agustina L , Virgianto R H , Fitrianto A N
Published: December 2021

IOD and ENSO are two global phenomena that are quite influencing the territory of Indonesia. Sumatra is one of the islands in Indonesia with unique local characteristics and is located in the westernmost. This study attempts to analyze how much the IOD and ENSO have affected rainfall in the Sumatra Island and which is more dominant, and the distribution that can be used as a reference in forecasting seasons and rainfall. In a period of 37 years (1981-2017), the influence of IOD and ENSO was analyzed using a correlation method which was then mapped. The rainfall data used was obtained from CHIRPS with a scale of 0.05. Data is processed using Climate Data Operator (CDO) and R-statistics to obtain correlation maps. Correlation calculations are carried out on the whole data and in the season period. The effect of IOD was seen to be significant in the southern part of Sumatra, with a maximum correlation of 0.4, while in the north and center, the correlation only -0.25. The effect of ENSO looks more evenly compared to the impact of IOD, with a correlation reaching -0.4 in the northern and southern parts of Sumatra. In contrast, the middle part shows a smaller correlation value with ranges of -0.1 to -0.3. In the DJF and MAM season periods, a positive correlation between rainfall and IOD occurred throughout Sumatra, and in the JJA and SON, a dominant-negative correlation occurred. In comparison, the ENSO shows dominant negative correlation in each period. Based on the correlation, ENSO is more influential on Sumatra compared to IOD in overall data. However, on seasonal data, IOD is more significant than ENSO. The southern part of Sumatra Island is the most affected by ENSO and IOD compared to other parts.
Forest and land fire smoke detection using GCOM-C data (case study: Pulang Pisau, Central Kalimantan)
Authors: Rahmi K I N , Febrianti N , Prasasti I
Published: December 2021

Forest/land fire give bad impact of heavy smoke on peatland area in Indonesia. Forest/land fire smoke need to be identified the distribution periodically. New satellite of GCOM-C has been launched to monitor climate condition and have visible, near infrared and thermal infrared. This study has objective to identify fire smoke from GCOM-C data. GCOM-C data has wavelength range from 0.38 to 12 μm it covers visible, near infrared, short-wave infrared and thermal infrared. It is relatively similar to MODIS or Himawari-8 images which could identify forest/land fire smoke. The methodology is visual interpretation to detect forest/land fire smoke using near infrared band (VN08), shortwave infrared band (SW03), and thermal bands (T01 and T02). Hotspot data is overlaid with GCOM-C image to represent the location of fire events. Combination of composite RGB image has been applied to detect forest/land fire smoke. GCOM-C image of VN8 bands and combination of thermal band in composite image could be used to detect fire smoke in Pulang Pisau, Central Kalimantan.
Evaluation of ECMWF model to predict daily and monthly solar radiation over Indonesia region
Authors: Sianturi Y , Sopaheluwakan A , Sartika K A
Published: December 2021

Solar radiation forecast is a pivotal information needed in the operational activity of large-scale solar energy production. In this study, the reliability of SSRD (surface solar radiation downward) forecast from the 51 ensemble members in the ECMWF (European Centre for Medium Range Forecast) long-range forecast to predict daily and monthly radiation in 5 climatological stations in Indonesia is evaluated. The global horizontal irradiance (GHI) data from the solar radiation observation network from January 2018 – December 2020 are used in the quantitative evaluation of the SSRD forecast. Post-processing methods are applied to the model output, namely the bilinear interpolation method and the empirical quantile mapping to reduce consistent biases in the model output. The evaluation was carried out for different cloud covers based on the calculation of clearness index (k_t). The cloud condition affects the performance of the model, where the highest correlation value is achieved during sunny days (0.18 – 0.65) and the lowest correlation happens in overcast days (0.05 – 0.35). Models also tend to underestimate radiation when the sky is clear and overestimate it in cloudy days, based on negative MBE values during clear days (-0.47 kWh/m2 – -1.29 kWh/m2). The spatial averaging method did not necessarily improve the accuracy of the forecast, but the empirical quantile mapping method provides better accuracy, which is indicated by a values (mean error ratio) lower than 1 in most stations. Information about the influence of cloud cover on model performance can be used in future application of the model output and the bias correction process carried out in this study can be applied to reduce bias in the model.
Impact Based Forecast analysis uses multi-model ensemble data and National Digital Forecast data in ArcMap 10.8.1
Authors: Salman R S , Ayufitriya
Published: December 2021

The number of people seeking public weather service information is growing, making it a challenge for all bureaus of meteorology around the world. Although, in the last decade, routine public weather service information has brought excellent weather forecast information for people and services to people with rapid, accurate, widely available, and easy to grasp information, which they may get in a variety of places, such as a website or an application. However, in this decade and in the future, it will not be enough. People want information such as what the impact should be and how people react to that impact, which should be displayed on a static Geographic Information System (GIS) map in a standard format. We will investigate and create an IBF map based on multi-model ensemble data and National Digital Forecast (NDF) data in this work. Then, using the GIS software ArcMap 10.8.1, we rank and score the geographic disaster data to determine the impact area. To create the effect area, we will employ primary and advanced methods of ArcMap 10.8.1. The information on the IBF map will be immediately understood by stakeholders and users.
Potential spesies from the Dipterocarp family at Mandailing Natal Forest Production Management Unit, North Sumatra, Indonesia
Authors: Latifah S , Zahrah M
Published: December 2021

Sumatra has extensive forests, rich in tree species, especially the Dipterocarpaceae species, which have high economic and ecological value in the development sector. The enormous number of Dipterocarpaceae species and the paucity of herbarium collections make identifying species quite easy. The study’s goal was to learn more about the Dipterocarpaceae family tree’s species, diameter, and height in the Mandailing Natal Forest Production Management Unit (KPHP ) in North Sumatra. Diameter and height data of Shorea sp was based on secondary data processing. The inventory revealed that the Dipterocarpaceae family has 12 different species. Trees in the Dipterocarpaceae family have an average diameter of 44.5 cm and a height of 20 cm. This inventory is expected to offer information on the several Dipterocarpacea families that can be found in this area, particularly those with high economic value and those that are protected.
Land use directions based on the level of land conversion vulnerability in the Padang Watersheds, North Sumatera
Authors: Purba S A , Slamet B , Rauf A
Published: December 2021

Hazardous land conversion in the Padang watersheds harms the hydrological conditions of the watersheds. Land use without considering the capacity and carrying capacity of the land results in decreased land productivity and increased watershed damage. This study aims to recommend directions for land use and land management in the Padang watersheds in areas that have a high and very high level of land conversion vulnerability. Analysis of land conversion vulnerability obtained by spatial modeling using ArcGis 10.3 software. The land cover data used in this study are data from the Ministry of Environment and Forestry in 2000 and 2019. Directions for land use are carried out through literature review in scientific journals, activity reports from both government and non-government agencies. Recommendations for land management directions are differentiated for urban areas and non-urban areas. Shrub cover that is vulnerable to conversion so that reforestation or other productive land uses are carried out with attention to soil and water conservation. Secondary dryland forest cover that is very vulnerable to conversion for partnerships with communities through community forestry/agroforestry schemes, rehabilitation and reforestation, and ecotourism. Plantation cover that is vulnerable to conversion can adopt an intercropping pattern of garden crops and seasonal crops. Agricultural land cover of dry land with high conversion vulnerability can adopt perennial crops at the land boundary and apply soil and water conservation. Residential areas in rural areas can adopt tree planting and make infiltration wells. The management direction for residential land in urban areas is to apply water conservation techniques (infiltration wells and polders) and arrangement of residential areas.
Carbon stock and vegetation estimation the abandoned pond, Pulau Sembilan, North Sumatra, Indonesia
Authors: Basyuni M , Simanjutak E O , Eddy S , Amelia R
Published: December 2021

The purpose of the study was to determine the species vegetation and carbon stock assessment derived from abandoned aquaculture ponds. Analysis of plant (tree, sapling, and seedling) was performed at Pulau Sembilan, Langkat, North Sumatra, Indonesia. The stage of the seedlings, saplings, and trees was analyzed from four transects. Each transect contained 100 m in length. Each estimated plot of a total of four transects comprised of 30 plots. The abandoned pond was dominated by Rhizophora apiculata and Bruguiera parviflora, the lowest on the species of Morinda citrifolia and Rhizophora mucronata. The diversity index of Shannon-Weiner was 1.44-1.72. The total biomass in the pond was 4,557.43 k/ha with a carbon potential of 2.10 tons/ha.
A review: hybrid simulation in forestry supply chain
Authors: Sembiring N , Napitupulu H L , Sembiring M T , Ishak A , Irwany F
Published: December 2021

Changes in supply chain availability in the forestry sector can significantly change efficiency responsiveness. This forestry supply chain network involves various processes such as harvesting, energy generation, wood, paper and board production. Methods that can be used to perform supply chain optimization are hybrid modelling and simulation. Substructure techniques with experimental testing methods that target numerical component conductors with communication loop components as well as transfer systems to form an entire system commonly referred to as Hybrid Simulation. In this study, we aim to find solutions so that the supply chain network in the forestry sector is not cut off by using hybrid simulation method. Hybrid simulations used can take into account when the supply chain will run out and prevent excessive exploitation so as to repair damage and recycle the supply chain so that it is not disconnected until the time period is taken into account. Each scientific article is rigorously selected to obtain articles that align with the purpose of this research.
Characteristics of forage garden vegetation of the Sumatran elephant (Elephas maximus sumatranus) in Medan Zoo
Authors: Zahrah M , Batubara R , Ardi R , Maulana M I , Auliah N L , Berutu A S
Published: December 2021

Medan Zoo is an ex situ conservation area for several wildlife species, covering an area of approximately 30 hectares, most of which are green open space and provide a forage garden for Sumatran elephants. This study aims to determine the characteristics of vegetation and the diversity of natural food types for elephants available in the Medan Zoo. Data collection using purposive sampling method, carried out in the forage garden which located in several points of elephant free-range. Based on the calculation of the Shannon-Wienner index, the overall diversity of plant species at the research location is 3.7 which can be categorized as high. The dominant understorey plants in the elephant forage garden are species from the family of Poaceae, namely Paspalumconjugatum, Eragrotisamabilis, Ottochloanodosa. Meanwhile, for speciesof trees habitus, the dominance for each level of vegetation starting from the tree, poles and saplings were: Meliaazedarach, Hibiscus tiliaceus and Cassia sp. There are types of elephant feed plants, classified into 8 families.The dominant type of natural feed is from the family of Poaceae.
Release of nickel ion and surface microstructure of NiTi archwire after immersion in tomato and orange juice
Authors: Lubis H F , Purba Y A
Published: December 2021

One of wires commonly used in orthodontic treatment is nickel-titanium (NiTi) archwire. NiTi archwire has the potential to release ions that can cause allergic and cytotoxic reactions. This study aimed to specify the difference in the amount of nickel ion release and surface microstructure of NiTi archwires after immersing in tomato and orange juice. NiTi archwire with a diameter of 0.016 inches and a length of 5 cm was used as the sample, which was immersed in 15 ml of solution and then stored at 37°C in an incubator for 24 hours. The samples were divided into two tretment groups (immersed in tomato and orange juice), each with nine samples. The immersion solution was tested for ion release using an Inductively Coupled Plasma–Mass Spectrometer. The microstructure of the wire surface was examined using a scanning electron microscope (SEM). The results revealed that group 1 has higher average amount of nickel ion release than group 2 and control. SEM result showed that the surface microstructure of the NiTi archwire in group 1 is roughest. There was a significant difference between the amount of nickel ion released and surface microstructure on NiTi archwire after being immersed in tomato and orange juice.
Physical and mechanical properties of four wood species from community forests in Binjai Regency, North Sumatra
Authors: Herawati E , Hartono R , Sinaga H M M
Published: December 2021

The fundamental properties of wood are significant to determine the purposes of wood used. This study aims to determine the physical and mechanical properties of four wood species namely terap (Artocarpus odoratissimus), durian (Durio zibethinus), mindi (Melia azedarachL.), and karet or rubber wood (Hevea brasiliensisMuell. Arg) from community forests in the Binjai Regency, North Sumatra. The physical properties were determined as described in ASTM D4442 and ASTM D2395 while the mechanical properties were conducted according to ASTM D143 and BS 373. The results showed the moisture contents of four wood species ranged 12.66– 15.28%, densities 0.35–0.59 gcm-3, and specific gravities (SG) 0.33–0.55. The compression, tensile and shear strengths parallel to the grain, hardness, modulus of elasticity (MOE), and modulus of rupture (MOR) ranged 20–35 MPa, 36–80 MPa, 6.5–9.7 MPa, 1713–3226 N, 5463– 7497 MPa and 43–71 MPa, respectively. Based on the SG and MOR values, the terap wood is included in strength class IV, while the other woods are in strength class III. Meanwhile, based on the compression strength values, the terap wood is included in strength class V, durian and mindi wood are in strength class IV, while karet wood is in strength class III.
Identification of land cover changes before and after forest and land fires in conservation areas of North Sumatra, Indonesia
Authors: Thoha A S , Sulistiyono N , Saraswita N , Wiranata D , Sirait S M , Inaldi R
Published: December 2021

Damage to conservation areas in North Sumatra can be mitigated by understanding the pattern of land cover change, which can be performed by detecting hotspots and their temporal and spatial patterns. This study aimed to explore land cover spatially and temporally before and after forest fires in the conservation areas in North Sumatra. Data on the hotspots, satellite imagery, land cover maps, and field verification were used to see the transition of land cover changes before and after forest and land fires. Temporal and spatial analysis was employed to see the trend of land cover changes of the land before and after the fires. Field verification was conducted through observations and interviews related to land cover conditions in the field caused by forest and land fires. This study found three conservation areas with the highest number of hotspots in 2014 in the period 2001-2019, including Gunung Leuser National Park (GLNP), Dolok Surungan Wildlife Reserve, and Barumun Wildlife Reserve during the 2001-2019 period. In 2010 and 2014 there were strong indications of a large area of land burning in three conservation areas. The burned land was near the outer boundary of the conservation areas and continued to expand into the areas over time. The area of the non-forest cover was relatively stable between periods prior to the discovery of several hotspots. Changes in forest cover to non-forest have become more widespread after the highest number of hotspots were detected in 2010. Conservation area management and various parties need to prevent the expansion of forest clearing considering the strategic role especially in GNLP as a world heritage.
Isolation and amplification of mangrove plants using DNA barcode in Percut Sei Tuan, North Sumatra, Indonesia
Authors: Syahbana R , Basyuni M , Siregar L A M
Published: December 2021

Mangroves are a collection of several species of trees or shrubs that distribute around the coastline and can survive in high salinity environments. Around 60% of mangrove forests in North Sumatra are reported to have been damaged, the main factors of this damage being the mangrove forests conversion into ponds and the expansion of oil palm plantations. Identification of mangrove species is very important in protecting and applying the biodiversity of mangrove forests. Identification of living things has evolved from morphological charcetrization to molecular identification. This study aims to explain the DNA isolation and PCR methods to identify mangrove species in North Sumatra. The results suggested that the rbcL primer used can detect mangrove species that were visualized in the form of DNA bands. The length of DNA fragments of mangrove species Acrosticum aureum ranged 632.0-619.6 bp, species Rhizophora apiculata 619.6-585.8 bp, species Nypa fruticans 600- 592.9 bp, species Avicennia alba 549.1-533.5 bp, species Hibiscus tiliaceus was not detected, and mangrove species Acanthus ilicifolius 480.3 bp.
The phenotypic of durian plant (Durio zibethinus Murr.) in Tapanuli Tengah Regency, North Sumatra, Indonesia
Authors: Sihaloho M A , Basyuni M , Hanafiah D S , Julianti E
Published: December 2021

Durian is a plant that is prone to genetic erosion. Exploration and characterization must be carried out to protect the local durian germplasm in Tapanuli Tengah Regency. This study aims to characterize the morphology of durian plants and determine the genetic relationship between the accessions of local durians in Tapanuli Tengah Regency. The research was done at Tukka, Sitahuis, and Kolang districts from December 2018 to February 2019 with a survey method using durian descriptor of IPGRI. Sampling techniques using purposive sampling with location judgment and morphological observation data were processed using NTSYS-pc 2.02 software and genetic relationship using the IBM SPSS (Statistical Package for the Social Sciences) program version 2.02 with cluster analysis. The result of the research showed that in Tukka, Sitahuis and Kolang district there were 75 accessions of durian been identified. The closest relationship is obtained on A61 and G71 originating from Kolang District with a similarity value of 7,345. The furthest relationship was obtained from A1 and A25 from Tukka district with the similarity value of 94,097.
Polyisoprenoid composition in chengham (Scyphiphora hydrophyllacea, Gaertn. f., Rubiaceae)
Authors: Basyuni M , Susilowati A , Susetya I E , Desrita  , Bimantara Y , Kajita T
Published: December 2021

Chengham (Scphyphora hydrophyllacea Gaertn. f., Rubiaceae) is a mangrove shrub or tree commonly in landward mangrove zones having some biological activities. All parts of S. hydrophyllacea have shown some components benefits to biological and pharmaceutical properties. This present study aimed to analyze the distribution and composition of polyisorenoid in senesnece leaves, fruits and branches of S. hydrophyllacea. Polyisoprenid patter was evaluated by two-dimensional thin layer chromatography (2D-TLC) approach. The total lipid (TL) content of five samples ranged from 5.7 mg/g in branches to 10.0 mg/g in the old leaves. Additionally, the percentage of polyprenol of senescence leaves slightly abundance compare to dolichol in the polyisoprenoid presence. Overall, polyprenol was found in higher content than dolichol in the yellow leaves. Results of this study found the type-II of S. hydrophyllacea fruits was in line with earlier reports on the plant fruits. The present study provided the occurrence of polyprenols and dolichols in S. hydrophyllacea tested organs.
Management of agricultural tools and machinery of SERASI program to improve food self-sufficiency in Banyuasin District of South Sumatra Province
Authors: Hasbil  , Hersyamsi  , Hananita Dauratri Ghirana
Published: December 2021

This study was carried out to find out the impact of utilized and without agricultural tools and machinery (alsintan) on farmers’ income in the SERASI program to achieve its optimal goal in Banyuasin District. This research was conducted from December 2020 to March 2021 at the Food Crops and Horticulture Department, BPP (Balai Penyuluhan Pertanian-Agricultural Extension Center) Muara Telang, Tanjung Lago and Rambutan Subdistricts. The descriptive method was used in this study with the tabulated presentation. The parameters used in this study were the comparison of mechanization and conventional use, the number of available tools and machines, and the impacts of using and without using alsintan on farmers’ income. The results showed that the average income of rice farming with alsintan in three study subdistrict were IDR 22,355,500, IDR 15,400,000 and. IDR 13,250,000 and without alsintan were IDR 7,830,000, IDR 6,950,000 and. IDR 6,528,000/ha per planting season. The SERASI program increased the Crop Index (IP 300) in Muara Telang Subdistrict, and IP 200 in Tanjung Lago and Rambutan Subdistricts. This showed that the Alsintan utilizing in agricultural processing from the soil processing until the harvesting was more effective compared to the process without alsintan.
Diversity of undergrowth understorey in Sibolangit Nature Park, Deli Serdang Regency, North Sumatra, Indonesia
Authors: Rambey R , Sitio A , Susilowati A , Rangkuti A B , Onrizal
Published: December 2021

The Sibolangit Nature Park area is one of the Nature Parks in North Sumatra which has various types of diverse plants ranging from understorey, epiphytes and various endemic tree species. The purpose of this study was to see the diversity of understorey species found in the Sibolangit Nature Park and its benefits. The results showed that there were 27 types of understorey plants from 18 families. Based on the family, the most commonly found were the Araceae family, namely 6 species (22.22%) and Zingiberaceae (11.11%). The understorey has the potential for medicinal plants, ornamental plants, poisonous plants, etc. The results showed that there were 15 species (55.5%) which were included in the category of ornamental plants, 7 species (25.92%) were included in medicinal plants, 1 species of poisonous plants (3.70%), 1 species of spice plants (3,70%), and 1 species (3.70%) protected plants and 2 species (7.40%) could not be explained scientifically. A protected and endangered plant species is Amorphophallus titanum
Instant porridge from natural local resources (orange sweet potato, carrot, and red bean) with highly nutritious as an alternative food source
Authors: Putra A , Nurminah M , Ginting S
Published: December 2021

Instant porridge is one of the food product that does not require a long time to serve. Instant porridge is usually made from rice flour. Food diversification is needed to make instant porridge more nutritious, one of which is making instant porridge from natural local ingredients such as orange sweet potato, carrot, and red bean. We made the composite flour that use to make instant porridge from mixture of orange sweet potato, carrot and red bean (orange sweet potato flour : carrot flour : red bean flour), namely P1 = 80% : 15% : 5%; P2 = 70% : 20% : 10%; P3 = 60% : 25% : 15%; P4 = 50% : 30% : 20%; P5 = 40% : 35% : 25%; P6 = 30% : 40% : 30%; P7 = 20% : 45% : 35%. The finalt result showed that the formulation composite flour in P7 = 20% orange sweet potato flour : 45% carrot flour: 35% bean flour was the best formulation and produce a good instant porridge by de-Garmo method.