Garuda - Garba Rujukan Digital

p-Index From 2020 - 2025

2.753

P-Index

This Author published in this journals

All Journal Jurnal Silvikultur Tropika (JST) Jurnal Ilmu dan Teknologi Kelautan Tropis Indonesian Journal of Geography JOURNAL OF COASTAL DEVELOPMENT Jurnal Penelitian Fisika dan Aplikasinya (JPFA) Jurnal Matematika & Sains Journal of Mathematical and Fundamental Sciences International Journal of Advances in Intelligent Informatics JURNAL ILMIAH PENDIDIKAN FISIKA AL BIRUNI Jurnal Fisika FLUX Science and Technology Indonesia Jurnal Penelitian Sains Jurnal Penelitian Pendidikan IPA (JPPIPA) IJEMS (Indonesian Journal of Environmental Management and Sustainability) Marine Research in Indonesia Jurnal Kelautan Nasional Jurnal Ilmu Fisika International Journal of Remote Sensing and Earth Sciences (IJReSES) Jurnal Teori dan Aplikasi Fisika Indobiosains SRIWIJAYA JOURNAL OF ENVIRONMENT JIFP (Jurnal Ilmu Fisika dan Pembelajarannya) Makara Journal of Science Kemas Journal:Jurnal Pengabdian masyarakat

Iskhaq Iskandar

University Of Sriwijaya

Author-ID : 289165

Agriculture, Biological Sciences & Forestry Astronomy Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Chemistry Civil Engineering, Building, Construction & Architecture Computer Science & IT Decision Sciences, Operations Research & Management Earth & Planetary Sciences Economics, Econometrics & Finance Education Electrical & Electronics Engineering Energy Engineering Environmental Science Immunology & microbiology Law, Crime, Criminology & Criminal Justice Library & Information Science Materials Science & Nanotechnology Mathematics Physics Public Health Social Sciences Transportation

Published : 42 Documents Claim Missing Document

Claim Missing Document

Articles

1 2 3 4 5

Analisis Pemodelan Data Pasang Surut Menggunakan Model TPXO 7.1 di Pelabuhan Tanjung Priok, Jakarta Utara Septi Hermialingga; Anna Is Purwiyanto; Iskhaq Iskandar
Jurnal Kelautan Nasional Vol 15, No 2 (2020): Agustus
Publisher : Pusat Riset Kelautan

Aktifitas pembangunan dan pelayaran di Pelabuhan Tanjung Priok sangat tinggi sehingga membutuhkan informasi pasang surut guna mendukung perencanaan pembangunan, alur keluar masuk kapal untuk bongkar muat barang, serta keselamatan pelayaran. Oleh karena itu, penelitian ini bertujuan untuk membandingkan karakteristik pasang surut observasi dengan karakteristik pasang surut prediksi model TPXO 7.1 dari perangkat lunak Tidal Model Driver (TMD) serta menganalisa keakurasian data pasang surut model TPXO 7.1. Metode penelitian yang digunakan untuk mengolah data observasi pasang surut menggunakan metode admiralty dan data prediksi pasang surut didapat dari model TPXO 7.1. Validasi data pasang surut dilakukan dengan menghitung Root Mean Square Error (RMSE) dan korelasi dari kedua data. Penelitian ini dilaksanakan bulan Maret 2018. Hasil analisis menunjukkan bahwa tipe pasang surut dari data prediksi model TPXO 7.1 dan data pengamatan langsung memiliki tipe pasang surut campuran dominan ke tunggal. Akurasi data pasang surut model TPXO 7.1 memiliki nilai RMSE sebesar 0.14 dan korelasi sebesar 0.73, dengan demikian data prediksi Model TPXO 7.1 dapat digunakan untuk menggantikan data observasi pada wilayah yang tidak diukur langsung.

The Rapid Changes of the Landscape Structure of the Meranti-Dangku Tropical Lowland Forest in the South Sumatra Province, Indonesia Zulfikhar Zulfikhar; Hilda Zulkifli; Sabaruddin Kadir; Iskhaq Iskandar
Sriwijaya Journal of Environment Vol 2, No 1 (2017): Green Environment For Human Welfare
Publisher : Program Pascasarjana Universitas Sriwijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (2448.324 KB)

The fragmentation of forest vegetation cover can be measured quantitatively, using tools that can characterize the geometry and spatial properties of the patch or patches of mosaic, which depicts the forest loss and the changes in the temporal pattern. The aims of this paper are to observe the process of the forest fragmentation, to find out the changes of spatial patterns of habitat continuum by applying the spatial dynamics change analysis of the forest fragmentation phases, and to provide the comprehensive approach in determining the rapid change of the forest landscape structure in the spatial transformation process, based on the decision tree models. We find three phases of the forest fragmentation were identified, namely dissection, dissipation, and attrition. This study shows that the production forest area and a wildlife conservation area that contiguous or borders, has the same phases in the process of fragmentation of the forest, but both have a difference of the magnitude of forest loss. We find there are at least five effects of forest fragmentation to the landscape structure, those are increasing in a number of habitat patches, decreasing in a size of habitat patches, reduction in a habitat amount, increasing in a dispersion and interspersion of patch types, and reduction in a size of spatial connectedness between patches.Keywords: fragmentation, landscape metrics, spatial transformation.

Impact of El Niño and El Niño Modoki Events on Indonesian Rainfall Iskandar, Iskhaq; Lestrai, Deni Okta; Nur, Muhammad
Makara Journal of Science Vol. 23, No. 4
Publisher : UI Scholars Hub

Show Abstract | Download Original | Original Source | Check in Google Scholar

On an interannual time-scale, the Indonesian climate is strongly influenced by the dynamics of Indo-Pacific climate modes. This study aims to investigate the possible impact of different types of El Niño events, namely, typical El Niño and El Niño Modoki, on Indonesian rainfall variability. Seasonal composite analysis was used to evaluate the magnitude and significance level of the influence of El Niño on the rainfall variability over the Indonesian region. Typical El Niño (hereafter El Niño) has a stronger influence on Indonesian rainfall than the El Niño Modoki during boreal autumn in September, October, and November when the events almost reach their peak. Cold sea surface temperature (SST) anomalies were observed in the Indonesian sea and in the western Pacific during El Niño years, while cold SST anomalies covered only the eastern Indonesian sea during El Niño Modoki years. Strong cold SST anomalies during El Niño years led to stronger low-level wind divergence over the Maritime Continent compared with that during El Niño Modoki years. In addition, the Walker circulation during El Niño years revealed a stronger downward motion over the Maritime Continent than that observed during El Niño Modoki years. This stronger downward motion (low-level wind divergence) during El Niño years reduced lower atmospheric water vapor and suppressed atmospheric convection over the Maritime Continent, leading to a significant decrease in rainfall. Similar situations were also observed during El Niño Modoki years but with a much weaker amplitude.

Mixed-layer Heat Budget in Western and Eastern Tropical Pacific Ocean during El Niño Event in 2015/2016 Kusuma, Willy Anta; Nur, Muhammad; Khakim, Mokhamad Yusup Nur; Iskandar, Iskhaq
Makara Journal of Science Vol. 24, No. 1
Publisher : UI Scholars Hub

Show Abstract | Download Original | Original Source | Check in Google Scholar

Temporal variation of mixed-layer heat budget at two contrasting locations, namely, western Pacific (warm water pool) and eastern Pacific (cold tongue) during the extreme El Niño phenomenon in 2015/2016 is evaluated. Oceanic and atmospheric datasets, including sea surface temperature (SST), wind stress, shortwave radiation (SWR), longwave radiation, latent heat flux (LHF), and sensible heat flux are analyzed. A slight warming occurred in the eastern tropical Pacific associated with a positive SST anomaly, which reflected the weakening or reversal of the trade winds. Meanwhile, the western tropical Pacific exhibited a cooling tendency during the development phase of El Niño. Analysis of the mixed-layer heat budget shows that the net heat flux due to SWR and LHF significantly contributes to the warming of the eastern tropical Pacific. The contribution from horizontal advection was extremely small on both sides. The analysis shows that the residual term significantly contributes to cooling (warming) tendency observed in the western (eastern) tropical Pacific. This condition may suggest that residual process due to entrainment and diffusivity played an important role in the evolution of cooling (warming) process in the western (eastern) tropical Pacific.

Characteristics of Diurnal Rainfall over Peatland Area of South Sumatra, Indonesia Puad Maulana Mandailing; Wijaya Mardiansyah; Muhammad Irfan; Arsali Arsali; Iskhaq Iskandar
Science and Technology Indonesia Vol. 5 No. 4 (2020): October
Publisher : Research Center of Inorganic Materials and Coordination Complexes, FMIPA Universitas Sriwijaya

The peak time of rainfall occurrence over an area has certain characteristics in which the difference in time and intensity of rainfall varies depending on its location and distance from the sea. This variation can be determined based on the phase and amplitude obtained using harmonic analysis. In this study, combined data from in-situ observation, satellite remote sensing and reanalysis were used to analyze spatial and temporal variations of peak rainfall events over peatland area of the South Sumatra Province. The results show that most of the South Sumatra Province has a diurnal peak of rainfall during afternoon ranging from 16.00 to 19.00 Western Indonesian Time. In addition, the results also indicate that the analysis on the in situ data revealed seasonal variation both in amplitude and time of maximum diurnal rainfall, while the reanalysis data only indicated a weak seasonal variation on the amplitude of the diurnal rainfall. Furthermore, spatial analysis shows that the time of maximum diurnal rainfall has spatial variation. Over the ocean, the time of maximum diurnal rainfall occurs during night time/early morning. Over the lowland or coastal area, the time of maximum diurnal rainfall occurs during afternoon, while over the high altitude (mountain) it occurs during late night.

Vertical Chlorophyll-a Concentration Profiles Observed on The Western Coast of Northern Sumatera During the 2017 Northeast Monsoon Iskhaq Iskandar; Qurnia Wulan Sari; Aan Johan Wahyudi; Afdal; Wijaya Mardiansyah
Science and Technology Indonesia Vol. 7 No. 1 (2022): January
Publisher : Research Center of Inorganic Materials and Coordination Complexes, FMIPA Universitas Sriwijaya

Subsurface chlorophyll-a (chl-a) concentration variability on Sumatera’s Northwestern coast is part of the phytoplankton biomass that supports and enriches the region’s fisheries supplies. During the 2017 northeast monsoon season from 25th November 25 to 11th December, the Ekspedisi Widya Nusantara (E-WIN) collected data from 16 stations. The finding demonstrates a rise in subsurface chl-a concentration as you get closer to the coast. Furthermore, the deep chl-a maximum (DCM) is only found offshore, with depths−3 between 30 to 50 m and chl-a concentrations of 0.07 to 0.25 mg.m. Surface chl-a concentrations near the coast were found to be high, ranging from 0.2 to 0.25 mg.m-3

El NiÃ±o Southern Oscillation (ENSO), Indian Ocean Dipole (IOD), and the Rise of Extreme Temperatures in Eastern Sumatra: Exploring Climate Change Dynamics Hamdi Akhsan; Muhammad Irfan; Iskhaq Iskandar
Jurnal Penelitian Pendidikan IPA Vol 9 No 2 (2023): February
Publisher : Postgraduate, University of Mataram

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29303/jppipa.v9i2.3084

The Indonesian region is affected by the monsoon system, which leads to a rainy season in December-March and a dry season in June-September. Global warming caused by human activities is increasing the risk of extreme climate events like floods, droughts, etc. The study aims to analyze the trends and correlations of extreme temperatures in the South Sumatra coastal area and its relationship with the DMI and Nino 3.4 indices. The four-stage research methodology includes data collection, extreme temperature index calculation, trend detection and correlation analysis with ENSO. Results indicate that the region has seen a rise in temperature, with hot day/night temperatures increasing by 0.26-0.29Â°C per decade and cold day/night temperatures by 2-3Â°C per 100-1000 years. A strong correlation was found between the DMI index and daily maximum/minimum temperatures, as well as between the Nino 3.4 index and the Diurnal Temperature Range (DTR). The study projects that nighttime temperatures will increase faster than daytime temperatures in the future, with a proportional correlation between the Nino 3.4 index and extreme temperatures

Pemodelan Numerik Hubungan Pola Curah Hujan Wilayah Equatorial di Pulau Sumatera Terhadap Fenomena ENSO dan IOD Melly Ariska; Adam Darmawan; Hamdi Akhsan; Supari Supari; Muhammad Irfan; Iskhaq Iskandar
Jurnal Teori dan Aplikasi Fisika Vol 11, No 2 (2023): Jurnal Teori dan Aplikasi Fisika
Publisher : Universitas Lampung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.23960/jtaf.v11i2.6593

A numerical modeling has been built for the relationship between rainfall in the equatorial region of Sumatra to the ENSO and IOD phenomena by taking data from 1991 to 2020 at three stations located in the western region of Sumatra Island, namely SM Japura, SM Minangkabau and SM Hang Nadim. The method used in this study is the method of correlation and linear regression on the Niño3.4 Index variable and the Dipole Mode Index on the amount of rainfall. The data visualization process is carried out with the output in the form of plots and graphs with Goole Colab coding. The resulting graph is a graph of the ENSO and IOD phenomena, as well as a regression graph between The Niño3.4, DMI and the amount of rainfall per month. This study was conducted with the aim of knowing how much influence the El Niño Southern Oscillation (ENSO) variable represented by the Niño3.4 Index and the Indian Ocean Dipole (IOD) represented by DMI had on rainfall in the equatorial region in the 1991 – 2020 period and to see the trend of significance between the two towards the equatorial region on the island of Sumatra. Rainfall in Indonesia's equatorial region tends to be influenced by IOD compared to ENSO. The combination of the two at the same time can cause a significant change in the amount of rainfall. La-Niña and negative IOD occurred in 1992, 1996, 1999, 2000, 2005, 2008, 2011 and 2016. The average rainy day index (SDII) tended to decrease in Japura Island in 1996, 2005, 2011, 2016 , at SM Minangkabau in 1992, 1996, 1999, 2000, 2016 and at SM Hang Nadim in 1996, 1999 and 2008. Meanwhile the longest series of wet days tended to decrease in SM Japura in 1992, 1996, 1999, 2005, in SM Minangkabau in 1992, 1996, 2005, 2008, and in SM Hang Nadim in 1992, 2000, 2005, 2008 and 2011. The longest series of dry days tended to increase in SM Japura in 1996, 2011, in SM Minangkabau in 1996, 2000, 2011, and at SM Hang Nadim in 1996.

Influence of Anomalous Upwelling on the Water Mass of South Java during Two Positive Indian Ocean Dipole in 2015 and 2019 Dominikus Krisna Herlambang; Iskhaq Iskandar
Jurnal Penelitian Pendidikan IPA Vol 9 No SpecialIssue (2023): UNRAM journals and research based on science education, science applic
Publisher : Postgraduate, University of Mataram

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29303/jppipa.v9iSpecialIssue.6182

Upwelling is a phenomenon that often occurs in the ocean. Upwelling can be interpreted as the process of rising sea water masses from below the surface to the surface due to the vacancy of sea water masses at the surface. The upwelling phenomenon will cause many anomalies that have a direct impact on ocean dynamics, one of which is the dynamics that occur in the waters south of Java. The formation of the coastal upwelling phenomenon in the waters south of Java in 2015 and 2019 was the cause of the active Positive IOD in both years. By carrying out time series analysis and spatial data visualization processes as well as correlation methods to determine the relationship between parameters, this research aims to discuss and find out about the influence of coastal upwelling dynamics on the waters of southern Java in 2015 and 2019. The results obtained from this research show that the coastal upwelling phenomenon formed in 2015 and 2019 along the waters of southern Java resulted anomalies in dynamic patterns in the form of decreasing sea surface temperatures and increasing chlorophyll-a concentrations

Coupled Ocean-Atmosphere Mode in the Tropical Indian Ocean during 2011 Iskandar, Iskhaq; Mardiansyah, Wijaya; Setiabudidaya, Dedi
Makara Journal of Science Vol. 18, No. 4
Publisher : UI Scholars Hub

Show Abstract | Download Original | Original Source | Check in Google Scholar

Coupled ocean-atmosphere mode in the tropical Indian Ocean, so-called the Indian Ocean Dipole (IOD), occurred

Co-Authors AA Sudharmawan, AA Aan Johan Wahyudi Adam Darmawan Afdal Agus Dwi Saputra Akmal Johan Aldri Frinaldi ANDY MULYANA Anindya Wirasatriya Anna IS Purwiyanto Apriani, Yosi Arsali Arsali Assaidah, Assaidah Azhar Affandi Azhar Kholiq Affandi Bahiyah, Amirotul Dedi Setiabudidaya Deni Okta Lestari Dominikus Krisna Herlambang Dwi Setyawan Eddy, Syaiful Edy Sutriyono Edy Sutriyono FAUZIYAH Fitri Agustriani Hadi Hamdi Akhsan Hilda Zulkifli Hilda Zulkifli Indra Yustian Jamiatul Khairunnisa Putri Keisuke Mizuno Khairul Saleh Khakim, Mokhamad Yusup Nur Khofaria, Hafizhu Kusuma, Willy Anta Lestrai, Deni Okta Melly Ariska Moh. Rasyid Ridho Mokhamad Yusup Nur Khakim Muhammad Abu Bakar Sidik Muhammad Hendri Muhammad Irfan Muhammad Irfan Muhammad Nur Nuril Azhar Nurjuliasti Ningsih, Ellis Pradanto Poerwono Puad Maulana Mandailing Putriyani, Fena Siska Qurnia Wulan Sari Raden Putra Rendy M. Wahid Rezi Apri Rozirwan . Sabaruddin Kadir Sabaruddin Sabaruddin SABARUDDIN, . Septi Hermialingga Sofian, Ian Mochamad Suhadi Suhadi Suhadi Suhadi Suhanda, Alfin Supari Supari Supari Supari, Supari Wijaya Mardiansyah Wijaya Mardiansyah Wijaya Mardiansyah Wijaya Mardiansyah Wijaya Mardiansyah Wijaya Mardiansyah, Wijaya Yukio Masumoto Zulfikhar Zulfikhar Zulfikhar, Zulfikhar Zulkifli Dahlan

Title

Found 42 Documents
Search

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Title Search

Found 42 Documents Search

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Title

Found 42 Documents
Search