NZ Coastal Classification
The NZ coastal classification looks at classifying the entire New Zealand coastline including the open coast and estuaries, rocky shores and unconsolidated shores. Shores and beaches were classified using the following broad parameters: Exposure; Coastal landform type; Foreshore sediment type; Hinterland characteristics. At present only the open coast unconsolidated shores and beaches have been classified as a starting point to keep the mapping task manageable.
Data Scope
The coastal database and classification have been developed through a combination of data mining from 1:50,000 topographic maps, aerial photographs, New Zealand Land Resources Inventory (NZLRI), the National Land Cover Data Base, (LCDB). There have been generous inputs from regional council staff and local experts, university staff and consultants. A collaborative project with the University of Sydney and Prof Andy Short capitalises on his 17 year effort mapping and classifying Australia’s 10,685 beaches to fast-track the beach type classification component of the project. Data extracted using GIS and other techniques are stored in a spatial database.
Mapping Methodology
The classification and mapping was structured to identify hazards such as rips, wave runup, wave climate, wind erosion and over topping by waves, along with related geomorphological metrics such as exposure, coastal landform type, foreshore sediment type, hinterland characteristics, beach type and other geomorphological features that have control on coastal processes. The classification and mapping was developed in the following stages.
1) Firstly a coastal classification scheme was developed by the study team based primarily on coastal geomorphology and oceanography using expert knowledge.
2) Expert panels were put together, incorporating members of the study team and local experts from University and Regional Council or private individuals to revise the classification and map the coast using workshops. Coastal features and beaches were identified on 1:50,000 scale maps. Additional information from the 1:250,000 geology maps, vertical aerial photos, oblique aerial photos and other sources were also used. As the coast was mapped the classification was revised. There was less iteration with the classification as the mapping progressed. The mapping process involved drawing information onto the 1:50,000 hard copy maps. The information was then entered into GIS.
The Classification
Classification table to be added at a later date.