1. Department of Geography, Geoinformatics and Meteorology, University of Pretoria, Pretoria, South Africa
2. Biological Invasions Directorate, South African National Biodiversity Institute, National Botanical Gardens, Pretoria, South Africa
3. GIS and Remote Sensing, CAD Mapping Aerial Surveyors, Pretoria, South Africa
4. South African Weather Service, Pretoria, South Africa
5. Institute for Soil, Climate and Water, Geoinformatics Division, Agricultural Research Council, Pretoria, South Africa