Regulatory Landslide Hazard Zoning in New Caledonia: Integrating Temporal Probability in a Quantitative Framework

A project was launched to produce landslide hazard maps for several municipalities in New Caledonia within a regulatory framework. A quantitative strategy was adopted to document and combine susceptibility, runout/propagation, temporal probability over a reference period, and intensity classes to assess hazard. Operationally, the implementation followed a stepwise "building-block" workflow, integrating each term of the hazard equation one by one to ensure traceability and maintain interpretability for non-specialist end users. Particular attention is given to how temporal probability is introduced and propagated through the workflow, and to how this choice affects the final hazard classes. A complementary, more probabilistically consistent alternative is also presented: a pixel-wise Poisson conversion applied to the continuous WoE output prior to reclassification. A case-study comparison highlights the respective strengths and limitations of both approaches.

Yannick Thiery, Bastien Colas, Mathieu Mengin, Yael Guyomard, Melody Premaillon, et al.. Regulatory Landslide Hazard Zoning in New Caledonia: Integrating Temporal Probability in a Quantitative Framework. Landslide Risk and Geo-Education, JTC-1 and JTC-3, Apr 2027, Queenstown, New Zealand. ⟨hal-05483025⟩
docType_s : COMM