Application of Rainfall Threshold for Sediment-Related Disasters in Malaysia: Status, Issues and Challenges

Abstract

Sediment-related disaster is one of the most significant natural disasters, from the perspective of magnitude, damage and loss to human life and infrastructure, and disruption to socio-economic activities. Debris, mud flood, landslide and cliff failure are the major catastrophic problems commonly experienced in most developing countries, including Malaysia. As rainfall is the main culprit to sediment-related disaster occurrences, rainfall data are crucial in the correlation of the occurred events. Several studies have been undertaken worldwide to estimate the critical rainfall conditions and draw the benchmark to predict landslide occurrences, specifically for debris and mudflows (DMF), and shallow landslides. Therefore, this paper presents an up-to-date picture on the development of the rainfall threshold from Malaysia’s perspective. Additionally, the open issues and challenges of deriving the rain threshold are also discussed in three aspects: collection of the dataset features, identification of the threshold and validation of the threshold. The outcomes of this review could serve as references for future studies in Malaysia and other developing countries in managing sediment-related disasters.

Development of Cumulative Rainfall Threshold for Landslide Occurrence in Peninsular Malaysia

“…Consequently, collection of rainfall records for extended period enhance reliability of empirical rainfall thresholds (Sen Zhang et al, 2023). Threshold parameter represents a rainfall index determined by amalgamation of rainfall intensity and cumulative rainfall (Ligong, S. et al, 2022). Rainfall threshold produced beneficial value in predicting landslide occurrences as an early warning system to ensure safety of lives and property (Adele Young et al, 2021;Yuniawan, R. A. et al, 2022;Won Young Lee et al, 2021).…”

“…Therefore, landslide early warning systems recommended to be established in Malaysia according to empirical relationship between precipitation and landslide occurrences through threshold development (Jamaludin, S. et al, 2011;Maturidi, A.M.A.M. et al, 2020;Ligong, S. et al, 2022). situated between latitudes of 6° to 1° N and longitudes of 100° to 105° E. It shares a border with Thailand in North, while to the south and southwest which across Strait of Malacca, adjacent to Singapore and Indonesian island of Sumatra.…”