Calculation of slope angle from bathymetry data using GIS - effects of computation algorithm, data resolution and analysis scale

Abstract

This report presents the results of a spatially nested case study using MAREANO multibeam bathymetry and regional data. The purpose of the case study was to investigate and illustrate common factors affecting terrain parameters derived from multibeam bathymetry data - computation algorithm, data resolution and analysis scale. Slope was selected as the focus of this study as it is one of the most commonly used variables, and also the most intuitive to illustrate. This study examines the effects of computation algorithm, data resolution, and analysis scale on slope values computed in a geographic information system (GIS) environment. The results of the study are discussed in relation to geomorphology and benthic habitat mapping which are key components of Norway's MAREANO seabed mapping programme.