Using remote sensing and spatial analysis to understand landslide distribution and dynamics in New Zealand

Landslides are a significant hazard to property and livelihoods, causing millions of dollars worth of damage annually in New Zealand. It is important to understand landslide hazards in order to mitigate their risks. Hazard maps are therefore used to help assess sites for building and infrastructure suitability. Current techniques for generating these maps are primarily based on slope, but it is recognised that vegetation and underlying geology also have a key role in influencing landslide susceptibility. The work contained herein analyses the spatial distribution of landslides in northern New Zealand after a single storm event and compares distribution characteristics to both vegetation and geology. This work demonstrates that neglecting these factors when generating hazard zones can lead to either an under or overestimate of the potential risk, depending on the determined threshold levels.