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Contact Name
Rezky Yunita
Contact Email
rezky.yunita@bmkg.go.id
Phone
+6282125693687
Journal Mail Official
jurnal.mg@gmail.com
Editorial Address
Jl. Angkasa 1 No. 2 Kemayoran, Jakarta Pusat 10720
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Kota adm. jakarta pusat,
Dki jakarta
INDONESIA
Jurnal Meteorologi dan Geofisika
ISSN : 14113082     EISSN : 25275372     DOI : https://doi.org/10.31172/jmg
Core Subject : Science,
Jurnal Meteorologi dan Geofisika (JMG) is a scientific research journal published by the Research and Development Center of the Meteorology, Climatology, and Geophysics Agency (BMKG) as a means to publish research and development achievements in Meteorology, Climatology, Air Quality and Geophysics.
Articles 174 Documents
PREDIKSI CURAH HUJAN BULANAN UNTUK PERINGATAN DINI LONGSOR DI BANJARNEGARA BAGIAN SELATAN DENGAN STATISTICAL DOWNSCALING DAN ENSEMBLE Agus Safril; Danang Eko Nuryanto; Ni Luh C. Chevi; Lisa Agustina; Ki Agus Ardi Z; Munawar Munawar; Faturrahman Faturrahman
Jurnal Meteorologi dan Geofisika Vol. 21 No. 2 (2020)
Publisher : Pusat Penelitian dan Pengembangan BMKG

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.31172/jmg.v21i2.698

Abstract

Banjarnegara merupakan wilayah pegunungan sehingga sering terjadi longsor. Curah hujan sebagai salah satu parameter cuaca dengan kondisi tertentu mampu memicu terjadinya longsor. Keberadaan prediksi hujan sangat diperlukan untuk informasi berbasis dampak (Impact Based Forecasting) sebagai media untuk mitigasi bencana. Tujuan penelitian ini untuk membuat peringatan dini potensi bahaya longsor bulanan dengan input prediksi curah hujan bulanan (faktor dinamis) dengan metode ensemble dan statistical downscaling (SD). Prediktor yang digunakan terdiri dari CAPE, PW, U850 dan V850 dan SST sebagai parameter atmosfer yang terkait fisis dan dinamis dengan curah hujan. Indeks kerawanan longsor (IKL) yang digunakan sebagai faktor statis untuk peringatan dini bahaya longsor meliputi parameter curah hujan tahunan, kemiringan lereng dan penggunaan lahan. Hasil IKL selanjutnya di-overlay dengan prediksi curah hujan dengan tiga kategori persentil, yaitu Curah Hujan < P33 (persentil 33%) sebagai curah hujan rendah, P33-P66 (sedang) dan >P66 (tinggi). Hasil prediksi model ensemble menunjukkan pola curah hujan mengikuti pola musim kemarau dan awal musim hujan (curah hujan prediksi sesuai dengan observasi). Hasil korelasi yang tinggi menunjukkan bahwa model prediksi layak digunakan sebagai masukan model untuk peringatan dini longsor. Nilai IKL menunjukan bahwa Wilayah Kecamatan Banjarnegara dan Wanadadi merupakan lokasi paling rawan longsor (3,625) kemudian Wanadadi (3,188) dan agak rawan Mandiraja (2,875). Hasil prediksi curah hujan kemudian dioverlay dengan tingkat IKL digunakan sebagai indikator peringatan dini. Hasil validasi dengan data observasi menunjukkan bahwa peringatan dini longsor mempunyai akurasi yang cukup baik (informasi peringatan dini sesuai umumnya dengan kejadian longsor).  Banjarnegara is a mountainous region so landslides often occur. Rainfall is one of the weather parameters with certain conditions that can trigger landslides. The presence of rain predictions is really crucial for impact-based information (Impact Based Forecasting) as a mechanism for disaster reduction. The purpose of this paper is to make an early warning of potential monthly landslides with monthly rainfall prediction input (dynamic factors) with the ensemble and statistical downscaling (SD) methods. Predictors used consisted of CAPE, PW, U850, and V850, and SST as atmospheric parameters related to physical and dynamic rainfall. To build an early warning of landslide hazards, the landslide susceptibility index (IKL) was employed using annual rainfall, slope, and land use parameters. The results of IKL are then overlaid with predictions of rainfall with three percentile categories namely Rainfall <P33 (percentile 33%) as low rainfall, P33-P66 (moderate), and > P66 (high). The results of the ensemble model predictions show that rainfall patterns follow the pattern of the dry season and the beginning of the rainy season (predicted rainfall is in accordance with observations). The IKL value shows that the Districts of Banjarnegara and Wanadadi are the most prone to landslides (3,625) than Wanadadi (3,188) and somewhat vulnerable to Mandiraja (2,875). The rainfall prediction results are then overlaid with the IKL level producing an index as an early warning indicator. The results of the validation with observational data indicate that early warning landslides have quite a good accuracy (early warning information is generally in accordance with landslide events).
ANALISIS FENOMENA URBAN HEAT ISLAND BERDASARKAN TUTUPAN LAHAN DI KOTA PEKANBARU Sasmita, Aryo; Darmayanti, Lita; Putra, Iqbal Perdana
Jurnal Meteorologi dan Geofisika Vol. 24 No. 2 (2023)
Publisher : Pusat Penelitian dan Pengembangan BMKG

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.31172/jmg.v24i2.710

Abstract

Pekanbaru City is the capital of Riau Province with a variety of very rapid development activities along with the increasing number of city residents, resulting in reduced vegetative land. This is the cause of the increase in surface temperature in Pekanbaru City, especially in the city center, which can accelerate the Urban Heat Island (UHI) phenomenon. The purpose of this study was to determine the distribution of surface temperature and identify the UHI phenomenon in Pekanbaru City. The research method is to identify the distribution of surface temperatures in the research period 2013-2018. Extraction of surface temperature comes from Landsat 8 imagery. The UHI phenomenon is seen from the temperature difference between the downtown area represented by Sukajadi Village and suburban areas, namely Kulim Village, Tebing Tinggi Okura, Muara Fajar, and Tuah Karya. The results showed that Pekanbaru City experienced the UHI phenomenon during the study period, because the temperature was already more than 30℃ and there was a temperature difference between the city center and the outskirts of the city that exceeded 3℃.
STUDI FREKUENSI KRITIS (foF2) PADA LAPISAN IONOSFER YANG BERHUBUNGAN DENGAN KEJADIAN GEMPA BUMI DI SEGMEN MENTAWAI TAHUN 2010-2015 Ashar Muda Lubis; Mawaddah Mawaddah; Afrizal B.; Halauddin Halauddin; Zainal Abidin
Jurnal Meteorologi dan Geofisika Vol. 22 No. 2 (2021)
Publisher : Pusat Penelitian dan Pengembangan BMKG

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.31172/jmg.v22i2.717

Abstract

Telah dilakukan kajian frekuensi kritis (foF2) lapisan F ionosfer untuk mencari apakah perubahan/anomali foF2 pada lapisan ini berhubungan dengan kejadian gempa bumi di segment Mentawai Sumatera Barat sehingga dapat digunakan sebagai prekusor gempa bumi dalam order harian. Untuk itu data ionogram pada waktu 2005-2015 yang merupakan hasil pengamatan ionosonda tipe Frequency Modulation Continous Wave (FMCW) di stasiun Kototabang, Kabupaten Agam, Sumatra barat, kemudian data aktivitas geomagnetik melalui indeks Disturbance Storm Time Index (DST) dan data aktivitas matahari (sunspot number) telah digunakan. Sementara itu sebanyak 37 kejadian data gempa bumi (Mw > 5,5) di wilayah Mentawai yang berasal dari USGS digunakan untuk mengkaji anomali foF2 terhadap kejadian gempa bumi selama 14 hari sebelum gempa bumi terjadi. Hasil pengamatan secara umum memperlihatkan terdapat anomali foF2 pada selang 14 hari sebelum terjadinya gempa bumi. Kemunculan foF2 tersebut dapat diduga sebagai indikasi sebagai aktivitas pre-seismic dalam kulit bumi pada 37 kejadian gempa bumi di wilayah Mentawai, meskipun kadang-kadang aktivitas geomagnet dan aktivitas matahari terlihat berpengaruh anomali foF2. Oleh karena itu diperlukan kajian lanjutan untuk menguji korelasi antara anomali foF2 dan kejadian gempa bumi secara statistik.
MEMBANGKITKAN DATA CUACA HARIAN DARI DATA BULANAN: STUDI KASUS SULAWESI UTARA Supriyadi, Eko
Jurnal Meteorologi dan Geofisika Vol. 24 No. 2 (2023)
Publisher : Pusat Penelitian dan Pengembangan BMKG

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.31172/jmg.v24i2.718

Abstract

The limited availability of daily data is a major issue when working with weather datasets. It can lead to discontinuities in the data history that impact the accuracy of the model output, which is a function of the observation input. This study presents a simple technique for generating daily weather data from monthly data using synoptic observations from the North Minahasa Climatology Station (1989-2014). Our approach involves the use of logit, Fourier, and gamma functions. The generated rainfall exhibits a similar pattern to the observed rainfall, and the statistical test indicates no significant difference (p<0.000). However, the resulting correlation is low (0.33-0.49). Based on the seasonal division, both the generated and observed rainfall values are high in the December[1]January-February (DJF) season, followed by a decrease in the March-April-May (MAM) and June-July-August (JJA) and an increase in the September-October-November (SON) season. Additionally, there are discrepancies in rainfall generation compared to observations due to the use of uniform distribution random numbers, which tend to overlook temporal specificity. Moreover, other meteorological factors, such as temperature and relative humidity, generate daily values from monthly data that closely resemble observations, with a correlation coefficient greater than 0.8. This is due to the Fourier function’s lack of a field variability factor.
PENGELOMPOKAN DATA GEMPA BUMI MENGGUNAKAN ALGORITMA DBSCAN Raisa Rizky Amelia Rahman; Arie Wahyu Wijayanto
Jurnal Meteorologi dan Geofisika Vol. 22 No. 1 (2021)
Publisher : Pusat Penelitian dan Pengembangan BMKG

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.31172/jmg.v22i1.738

Abstract

Gempa bumi merupakan bencana alam yang tidak dapat dicegah maupun dihindari. Oleh sebab itu, perlu dilakukan pemetaan dan pengelompokan wilayah gempa untuk mendukung upaya minimalisasi dampak yang ditimbulkan. Data yang digunakan dalam penelitian ini adalah data gempa bumi di Indonesia yang bersumber dari Badan Meteorologi, Klimatologi, dan Geofisika (BMKG). Penelitian ini menggunakan algoritma DBSCAN dalam mengelompokkan data ke dalam beberapa cluster. Metode untuk menguji validitas hasil cluster adalah dengan menggunakan Silhouette Coefficient dan Gamma Index. Hasil clustering pada penelitian ini memberikan kesimpulan bahwa dengan menggunakan algoritma DBSCAN diperoleh 3 cluster wilayah beresiko terjadi gempa bumi berdasarkan karakteristik parameter gempa bumi yang dihasilkan. Kombinasi nilai ε dan MinPts yaitu 0,28 dan 3 menghasilkan nilai Silhouette Coefficient sebesar 0,81091 dan Indeks Gamma sebesar 0,98104 yang menggambarkan bahwa DBSCAN mampu mengelompokan wilayah berpesiko terjadi gempa bumi dengan cukup baik. Hasil penelitian ini dapat digunakan sebagai bahan pertimbangan suatu instansi dalam pengambilan keputusan terkait penanganan (mitigasi) bencana gempa bumi.
Estimasi Suhu Udara Di Kabupaten Manokwari Melalui Pemanfaatan Citra Satelit Landsat 8 Mashudi Mashudi; Arif Faisol
Jurnal Meteorologi dan Geofisika Vol. 23 No. 1 (2022)
Publisher : Pusat Penelitian dan Pengembangan BMKG

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.31172/jmg.v23i1.753

Abstract

Air temperature is the main parameter in determining agricultural land. However, most areas in Manokwari do not have air temperature data due to limited meteorological stations. The utilization of Landsat 8 satellite imagery is one of the alternative solutions for providing air temperature data. This study aims to examine the performance of Landsat 8 satellite imagery in estimating air temperature in Manokwari. The air temperature is estimated using the Normalized Difference Vegetation Index (NDVI) approach. Seven (7) statistical parameters i.e mean error (ME), mean absolute error (MAE), root mean square error (RMSE), relative bias (RBIAS), mean bias factor (MBIAS), percent bias (PBIAS), and the Pearson correlation coefficient (r) are used in the test. Besides, a paired T-test was also used to determine the significance of the difference between the estimated and observed data. A total of 33 Landsat 8 satellite imagery recordings from 2015 to 2020 and air temperature data obtained from the climatological station were used. The results showed that the estimated temperature had good accuracy with ME = 0.50 oC, MAE = 2.73 oC, RMSE = 3.45 oC, RBIAS = 0.09, MBIAS = 1.00, and PBIAS = 9,16% compared with climatological data. Besides, the estimated temperature does not have a significant difference to observed data although it has a weak correlation with r = 0.31. Therefore, Landsat 8 satellite imagery can be used as an alternative solution in providing air temperature in Manokwari for supporting agricultural land development.
PENGARUH CENS-CT TERHADAP CURAH HUJAN EKSTRIM DAN BANJIR DI KOTA SEMARANG (STUDI KASUS TANGGAL 5 DAN 6 FEBRUARI 2021) Zauyik Nana Ruslana; Sulistyowati Sulistyowati; Umaroh Umaroh; Rudi Setro Prihatin; Sri Endah ANA
Jurnal Meteorologi dan Geofisika Vol. 23 No. 2 (2022)
Publisher : Pusat Penelitian dan Pengembangan BMKG

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.31172/jmg.v23i2.761

Abstract

Pada awal bulan Februari 2021, CENS (Cross Equatorial Northerly Surge) mengalami lonjakan aliran permukaan dari LCS (Laut Cina Selatan) hingga mencapai pesisir Pulau Jawa sehingga memicu aktivitas kuat konveksi yang berpotensi hujan dengan intensitas Sangat Lebat – Ekstrim. Analisa dari wilayah CT (Cold Tongue) menunjukkan penjalaran suhu dingin dari LCS bersamaan dengan CENS hingga Laut Jawa yang berpotensi memperburuk untuk terjadinya hujan ekstrim. Transpor uap air di khatulistiwa dari BBU (Belahan Bumi Utara) ke BBS (Belahan Bumi Selatan) secara klimatologis terjadi pada periode DJF (Desember-Januari-Februari). Berdasar analisa pada dasarian ke-1 bulan Februari 2021 aliran uap air berasal dari Pasifik Barat dan LCS serta Samudera Hindia bagian Selatan Pulau Sumatera dan Jawa. Kejadian hujan ekstrim juga dibuktikan dengan peningkatan transportasi uap air pada low level (1000 - 850 mb) mulai pukul 01.00 LT dan meningkat tinggi pada pukul 03.00 - 04.00 LT kemudian turun pada pukul 05.00 - 06.00 LT, sedangkan dari transportasi uap air pada ketinggian 1000 - 500mb juga menunjukkan banyaknya transportasi uap air sejak pukul 01.00 - 06.00 LT. Dari distribusi curah hujan tanggal 5 Februari 2021 juga menunjukkan tingginya curah hujan hingga level ekstrim dari pesisir Kota Semarang (Kecamatan Tugu, Ngaliyan dan Semarang Barat) hingga level hujan lebat di wilayah Selatan Kota Semarang (Kecamatan Tembalang dan Banyumanik), bila distribusi pada dasarian ke-1 bulan Februari 2021 dibandingkan dengan normalnya adalah lebih tinggi. Berdasarkan historis kejadian banjir, bulan Februari  tertinggi kedua setelah bulan Januari. dalam periode tahun 2008 - 2020 kejadian banjir pada bulan Februari di Kota Semarang mengalami peningkatan signifikan. Sinkronisasi data hujan dengan kejadian banjir periode tahun 2021 - 2020 terdapat kaitannya antara banjir dan hujan dengan intensitas lebat - sangat lebat
AQUIFER VULNERABILITY EVALUATION IN SOUTHWESTERN NIGERIA FROM AHP-GODT MODEL USING GEO-ELECTRICAL DERIVED PARAMETERS Saminu Olatunji; Ahmed Muyiwa Emiola; Adewale Warith Adebisi
Jurnal Meteorologi dan Geofisika Vol. 22 No. 1 (2021)
Publisher : Pusat Penelitian dan Pengembangan BMKG

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.31172/jmg.v22i1.764

Abstract

The study aimed  to determine the exposure levels of the subsurface aquiferous layers, owing to the alarming rate of contamination of the groundwater within 8.150 0N - 8.156 0N and 4.244 0E - 4.248 0E. Thus, aquifers' overlying layers, resistivity, and thickness anomalies were determined to generate an aquifer vulnerability map. A multi-criteria decision method of estimated Groundwater confinement, Overlying strata, Depth to Aquifer, and Topography index approach was implemented. Schlumberger's Vertical Electrical Sounding technique was implemented to acquire 30 Vertical Electrical Sounding points under a maximum half-current electrode separation (AB/2) of 65 m. IP2Win geophysical software packages were used to analyze the varying layer resistivity, depth, thickness, and also the sounding curves of the study area. The 2D model revealed a maximum of four geo-electric layers. The layers' resistivity and thickness ranges are clayey silt topsoil (52.5-1104 Ωm; 0.5-9.59 m), weathered layer (10.3-804 Ωm; 0.6-12.1 m), fractured basement (5.5-50832 Ωm; 6.7-18.1 m) and fresh basement (8.3-27348 Ωm; infinity m). On the Groundwater Overlying Strata Depth to Aquifer and Topography model scale, the area is generally characterized by the moderate vulnerability. Implying here is that aquifers have a moderate protective capacity in which the overlying strata above the aquifer are mostly impermeable layers (clay and silt) of high thickness and low porosity.
Analisis Perubahan Parameter Fisis dan Kimiawi Sebagai Studi Prekursor Gempa Bumi di Wilayah Yogyakarta Divyana Meidita; Agustya Adi Martha; Yosi Setiawan; Supriyanto Rohadi
Jurnal Meteorologi dan Geofisika Vol. 22 No. 1 (2021)
Publisher : Pusat Penelitian dan Pengembangan BMKG

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.31172/jmg.v22i1.766

Abstract

Gempa merusak pernah terjadi di sekitar Sesar Opak, Yogyakarta pada 27 Mei 2006 dengan kekuatan 6,3 Mw. Sebagai upaya mitigasi, BMKG melakukan pengamatan parameter fisis dan kimiawi dengan memasang sensor parameter prekursor di Stasiun Pundong dan Piyungan, Yogyakarta. Data parameter prekursor (radon, geotemperatur, suhu udara, dan ketinggian air tanah) diperoleh dari Pusat Penelitian dan Pengembangan (Puslitbang) BMKG, sedangkan data parameter gempa bumi diperoleh dari katalog BMKG dengan kriteria magnitudo  dan jarak episenter dalam radius km pada tahun 2018. Penelitian ini menganalisis variasi nilai parameter prekursor yang berasosiasi dengan aktivitas gempa bumi di wilayah Yogyakarta. Pengolahan data mengacu pada beberapa penelitian terdahulu dengan menggunakan metode statistik. Validasi dilakukan secara kuantitatif menggunakan data curah hujan dan secara kualitatif menggunakan data kondisi geologi dari studi literatur. Hasil penelitian menunjukkan adanya indikasi perubahan nilai parameter prekursor sebelum gempa bumi dengan variasi nilai yang dipengaruhi oleh besarnya parameter gempa, tetapi masih sulit dibedakan apakah anomali terjadi akibat aktivitas tektonik atau kondisi meteorologis.
STRESS ANALYSIS AND CHARACTERISTICS DUE TO THE SOUTH JAVA EARTHQUAKE, APRIL 10, 2021 Sulastri Sulastri; Rahmat Setyo Yuliatmoko
Jurnal Meteorologi dan Geofisika Vol. 24 No. 1 (2023)
Publisher : Pusat Penelitian dan Pengembangan BMKG

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.31172/jmg.v24i1.770

Abstract

The April 10, 2021, earthquake in the south of East Java was classified as destructive. The secondary impact of this earthquake was quite significant. Many houses collapsed, and not a few casualties. This earthquake is unique because usually, destructive earthquakes occur at shallow depths, but earthquakes with a magnitude of 6.1 are classified as medium-depth earthquakes at sea. The earthquake in the south of East Java is classified as an intraplate earthquake because it is located on the continental plate, not in the plate contact area. The question is whether the damage that occurred to the building was purely due to the magnitude of the stress released by the earthquake or whether there were other factors. This study uses seismogram data for the earthquake south of East Java on April 10, 2021, with a radius (∆) of 300-1000 recorded at MEEK, MORW, and ARMA stations in Australia. It calculates the amount of stress based on the stress drop, while the stress column determines the stress mechanism. Calculation of stress drop from the source spectrum is obtained by the deconvolution method, namely the seismogram component separation technique in the form of Source (f), Path (f), Site (f), and Instrument (f). The analysis of the observed displacement spectrum used the Nelder Mead Simplex nonlinear inversion method. Meanwhile, the Stress Columb calculation was obtained using the Columb 3.3 program from the United States Geological Survey (USGS). The result of this research is that the stress drop value is 1.69 MPa, with the type of focus mechanism being a thrust fault in the sea. The earthquake in the south of East Java was caused by rock activity in the intraplate. The value of the stress drop is more significant when compared to the subduction contact area. This area is of intraplate rock with various variations, and earthquakes are rare. This study aims to analyze the stress, both the magnitude of the stress drop and the mechanism of the column stress results, so that the stress caused by the earthquake can be known and why the earthquake in the south of East Java is destructive. The quake in Southeast Java is classified as dangerous, not because of the magnitude of the stress generated or its mechanism. The damage was due to the amplification of earthquake waves in the building. The injury occurred because most of the buildings were built on soft soil, especially in several areas in East Java, such as Lumajang, Pasuruan, Trenggalek, Probolinggo, Ponorogo, Jember, Tulunggagung, Nganjuk, Pacitan, and several urban areas, namely Blitar, Kediri, Malang, and Stone. So, there is a need for earthquake disaster mitigation, especially in densely populated areas that live on soft soil. This mitigation effort is to minimize the occurrence of casualties by building buildings according to earthquake-resistant standards and avoiding development in the regions that have the potential for amplification of earthquake waves.

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