Bartlett Lewis Rectangular Pulse (BLRP) Approach with Proportional Adjusting Procedure in Rainfall Disagregation Method in Hidrology Laboratory of Brawijaya University Rain Station

Rainfall data is one of the information that can be used in flood prevention, especially low-scale rainfall data (hourly). However, the availability of hourly rainfall data is very limited. It is because not all rain stations have hourly rain gauges which are quite expensive. This research aims to obtain hourly rainfall data based on daily rainfall data with the Bartlett Lewis Rectangular Pulse (BLRP) stochastic disaggregation method. This method was applied to rainfall data at the Hydrology Laboratory of Brawijaya University Malang in 2016. There are six BLRP parameters, namely λ, ν, κ, μ_x, α, φ which are used to produce hourly rainfall data. To maintain the consistency of hourly rainfall data based on daily rainfall data, a proportional adjusting procedure is used. The results showed that the disaggregation method of the BLRP approach can produce good enough hourly rainfall data that is consistent with daily rainfall data, seen from the in-sample MAE value of 0.5348 and 0.3113 for out-sample MAE.