Jurnal Penelitian Pendidikan IPA (JPPIPA)
Vol 11 No 11 (2025): November: In Progress

English Language

Jauhari, M. Reza (Unknown)
Suhartanto, Ery (Unknown)



Article Info

Publish Date
25 Nov 2025

Abstract

Reliable precipitation data are essential for hydrological modeling in data-scarce basins. This study evaluates five statistical bias-correction methods—Correction Factor (mean-ratio scaling), Linear Scaling (mean adjustment), Linear Regression, Local Intensity Scaling (LOCI; wet-day threshold and intensity adjustment), and Power Transformation—to improve satellite rainfall for the Gembong Watershed, Pasuruan, East Java, Indonesia. We used daily TRMM (2004–2013) and GPM IMERG (2014–2023) estimates harmonized to a common grid and time step and compared them with gauges using Pearson’s r, Nash–Sutcliffe Efficiency (NSE), and the RMSE-observation standard deviation ratio (RSR). LOCI delivered the best overall balance (NSE = 0.92; r = 0.84; RSR = 0.55), while Linear Scaling achieved a slightly lower NSE but the smallest RSR (NSE = 0.87; RSR = 0.49). Power Transformation showed limited skill (NSE = 0.57; RSR = 0.90) despite high correlation. Ranking prioritized NSE with r and RSR as supporting metrics. The coastal-lowland setting of Pasuruan—with strong convective rainfall and heterogeneous land use—makes accurate bias correction particularly consequential for flood and water-resources analysis. We conclude that LOCI’s adaptive thresholding is well-suited to such regimes and that the comparative framework aids method selection for similar data-scarce watersheds.

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Journal Info

Abbrev

jppipa

Publisher

Subject

Agriculture, Biological Sciences & Forestry Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Chemistry Education Materials Science & Nanotechnology Physics

Description

Science Educational Research Journal is international open access, published by Science Master Program of Science Education Graduate Program University of Mataram, contains scientific articles both in the form of research results and literature review that includes science, technology and teaching ...