A national scale coastal change dataset for Aotearoa New Zealand.

Abstract

Comprehensive historical coastal change datasets are crucial resources for effective coastal management. In Aotearoa New Zealand, available coastal change data is outdated, or sporadic, hindering large-scale, long-term analysis of coastal change, and coastal planning nationwide. Here we introduce New Zealand's Coastal Change Dataset (NZCCD) a detailed record of coastal change around New Zealand from the early 1940's to 2023. NZCCD was generated through a nationally consistent, rigorous process in which five coastal scientists manually interpreted and digitized the position of the coastline along New Zealand's open and soft cliffed coasts, using historic aerial photographs and high-resolution satellite imagery. NZCCD provides two datasets i) NZCCD Coastlines, comprising manually mapped coastlines, and ii) NZCCD Coastal Change Rates, 228, 611 points where rates of coastal change were calculated. The dataset enables a significant advancement in coastal management enhancing our understanding of the patterns and drivers of coastal change around New Zealand.