Cosine: A tool for constraining spatial neighbourhoods in marine environments

Spatial analysis methods used for detecting, interpolating, or predicting local patterns in geographic data require delineating a neighbourhood to define the extent of the spatial interaction. Certain spatial analysis methods, such as interpolation, have implemented the concept of directionality and barriers. However, not all approaches take into consideration geographic or environmental constraints such as impassable mountain ranges, road networks, or coastlines. Specifically, complex marine landscapes and coastlines pose problematic neighbourhood definitions for standard neighbourhood matrices used in the spatial analysis of marine environments. Here, we offer a new approach to constraining spatial neighbourhoods when conducting geographical analysis in marine environments. We developed methods and open source software (COnstraining SpatIal NEighbourhoods—COSINE) for modifying spatial neighbourhoods, and demonstrate their utility with a marine study of oil spills. The COSINE graphical user interface allows users to modify the most common standard spatial neighbourhood definitions such as fixed distance, inverse distance and k-nearest neighbour.