ANALISIS HUBUNGAN INDEKS HUJAN TERHADAP INDEKS BANJIR DI DAS JANGKOK
Analysis of the Relationship between Rainfall Index and Flood Index in the Jangkok Watershed
DOI:
https://doi.org/10.59896/gara.v20i1.580Keywords:
Rainfall, Flood, Jangkok Watershed, SPI, SSIAbstract
Imbalances within the hydrological system, such as irregular rainfall distribution, can trigger hydrometeorological disasters, particularly floods. This study aims to determine the correlation between rainfall indices and flood occurrences in the Jangkok River, employing a statistical approach to elucidate the relationship between two variables. The rainfall index method used is the Standardized Precipitation Index (SPI), a statistical measure that calculates rainfall deviation from the long-term mean over specific timescales. Meanwhile, the flood index is analyzed using the Standardized Streamflow Index (SSI), which assesses wet or dry conditions of an area based on river discharge data. This research examines the relationship between monthly SPI-1 and monthly SSI-1 using Pearson correlation method. The results show correlation coefficient (r) of 0.405 between the SPI-1 rainfall index and the SSI-1 flood index. This indicates a moderate positive relationship, meaning that increase in the rainfall index tends to be followed by increase in the streamflow (flood) index. Consequently, the SSI flood index can be explained by 16% of SPI rainfall index, while the remaining 84% is influenced by other factors. In other words, 16% of flood events at the study site directly influenced by rainfall, whereas majority driven by other factors affecting hydrological.
References
Alfiansyah, M. (2022). Analisis Penjalaran Kekeringan Meteorologi Menuju Kekeringan Hidrologi Pada DAS Pelaparado Kabupaten Bima. [Skripsi, Universitas Mataram]. Repositori Universitas Mataram.
Aripbilah, S. N., Suprapto, H. (2021). Analisis Kekeringan di Kabupaten Sragen dengan Metode Palmer, Thornthwaite dan Standardized Precipitation Index (SPI). Jurnal Sumber Daya Air, 17(2): 348-354.
Azkia, N., Yasar, M., & Syahrul, S. (2024). Analisis Perubahan Indeks Kekeringan Menggunakan Metode SPI (Standardized Precipitation Index) di Kabupaten Aceh Besar. Jurnal Ilmiah Mahasiswa Pertanian, 9(4): 374–382.
Balai Besar Wilayah Sungai Nusa Tenggara I. (2025). Laporan Pengelolaan Sumber Daya Air Wilayah Sungai Lombok. Kementerian Pekerjaan Umum dan Perumahan Rakyat.
Dewita, M., Harisuseno, D., & Suhartanto, E. (2022). Analisis kekeringan meteorologi dengan metode Standardized Precipitation Index (SPI) dan China Z Index (CZI) di Sub DAS Kadalpang, Kabupaten Pasuruan. Jurnal Teknologi dan Rekayasa Sumber Daya Air, 2(1): 1–13.
Faisal, Z. (2024). Penggunaan Model RRI (Rainfall Runoff Inundation) Untuk Prakiraan Genangan Di Das Tallo= The Utilization of the RRI model (Rainfall Runoff Inundation) for Predicting Inundation in The Tallo Watershed (Doctoral dissertation, Universitas Hasanuddin).
Harto, B.R. (1993). Analisis Hidrologi. Jakarta: PT. Gramedia Pustaka Utama.
Hidayat, M. D. N., Indarto, M., Askin, M., & Andriyani, I. (2019). Kecenderungan hujan ekstrem di Unit Pelaksana Teknis Pengelolaan Sumberdaya Air di Pasuruan, Jawa Timur. Jurnal Teknologi Industri Pertanian, 29(3): 173–182.
McKee, T. B., Doesken, N. J., & Kleist, J. (1993). The relationship of drought frequency and duration to time scales (Research Paper No. 92-1). Colorado State University, Atmospheric Science Paper.
Pradesi, R. F., & Sumarsono, A., Emiliawati, A. (2023). Analisis pengaruh variabilitas curah hujan terhadap perubahan debit sungai, karakteristik hidrologis, dan risiko banjir (Studi kasus: Sungai Musi Desa Muara Kelingi). Jurnal Sipil dan Perencanaan, 1(2): 59–68.
Pratama, M. R., Fahri, S., Andara, A., Anshary, A. J. H., & Nur, A. S. (2025). ANALISIS POTENSI BENCANA BANJIR DENGAN DATA CURAH HUJAN DI KECAMATAN BANGGAE TIMUR KABUPATEN MAJENE. Jurnal Teknik Sipil: Rancang Bangun, 11(02), 153-159.
Putri, N., Saidah, H., Budianto, M. B. (2020). Analisis Pola Kecenderungan Kekeringan dengan Metode SPI dan PDSI di Kabupaten Lombok Barat dan Lombok Tengah. [Skripsi Universitas Mataram] Repository Universitas Mataram.
Ramdhani, M. Z., Wibowo, A., & Prasetyo, B. (2023). Perbandingan Standardized Precipitation Index dan Standardized Anomaly Index untuk Penentuan Tingkat Kekeringan di Kabupaten Sragen, Jawa Tengah. Jurnal Sains dan Teknologi, 9(1): 45–54.
Soewarno, (1995). Hidrologi Aplikasi Metode Statistik untuk Analisa Data. Bandung: NOVA.
Wahyuning, S. (2021). Dasar-Dasar Statistik. Semarang: Yayasan Prima Agus Teknik.
World Meteorological Organization. (2012). Standardized Precipitation Index User Guide (WMO-No. 1090). Geneva: WMO.
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