PEMODELAN INTENSITAS HUJAN SEBAGAI FUNGSI DARI DURASI HUJAN DAN PROBABILITAS (Studi Kasus: Wilayah DAS Lesti, Malang, Jawa Timur) - sugiarti, anggun; Harisuseno, Donny; Yuliani, Emma (Fakultas Teknik, Universitas Brawijaya, 2015)
Abstrak: Mengenal dan memformulasi pola hujan bermanfaat dalam upayapengendalian dampak negatif akibat hujan.Intensitashujandanprobabilitashujanadalah variabel penting dalam perencanaan teknis. Penelitianinibertujuanuntukmemperolehsuatu model intensitashujanyangdapatmemprediksiintensitashujan padadurasilaindanprobabilitas secara akurat.Persamaantersebutdibandingkandenganmetode Talbot, Sherman,danIshiguro.Untuk memperkuat hasil pemodelan dilakukan uji verifikasi melalui perbandingan debit dari intensitas hujan pemodelan dengan debit pengamatan di Tawangrejeni. Hasilpersamaanmodelintensitashujantergolongbaikjika dibandingkandenganhasilpengamatan perdurasi.Haliniditunjukkandengannilai koefisien korelasi>0.831dankoefisienNash-Sutcliffe>99.Persamaan akhir pola intensitas hujan hasil pemodelanadalahIt.p=15,92e-0,025p+4,4312e-0,012p.(1/t). Prediksi intensitas hujan (It.p) pada sembarang durasi (t;jam) dan probabilitas hujan (p;%) dapat dilakukan dengan menggunakan persamaan ini.Kata kunci: Pemodelan, IntensitasHujan, Durasi, ProbabilitasÂ Abstract: Recognizing and formulating the rainfall intensity are very helpful to control the negative effects of rain. Rainfall intensity and rainfall probability are important for technical planning. This research aims to find a rainfall intensity model which can accurately predicts both of rainfall intensity on other duration and the probability.Further,this formula compared to the rainfall intensity formula based onTalbot, Sherman, and Ishiguromethods.The verification tests through comparison between the discharge of rainfall intensity model and observation discharge in Tawangrejeni were used to affirmthemodel. The result of rainfall intensity model is quite good compared to periodic observationof rainfall intensity.This is indicated by the correlation coefficient (>0.831) and Nash-Sutcliffe coefficient (>99).The final equation of rainfall intensity modelis It.p=15,922e-0,025p+4,4312e-0,012p.(1/t).Rainfall Prediction (It.p) on any duration (t;h) and rainfall probability (p;%)can be done by usingthis equation. Keywords: Modeling, Rainfall intensity, duration, probability