The Normalized Difference Vegetation Index (NDVI) is based on satellite measurements of radiation reflected by the Earth’s surface. Different characteristics of the reflected spectra can be combined to identify green vegetation – trees, grass and other plants. The NDVI has been widely used to study greenness and health. We are compiling a complete set of NDVI data covering all of Canada from the 1980s to the present. This will expand our potential to conduct additional studies to see if relationships between greenness and health are similar across Canada and in comparison to other countries.
Capturing different greenness qualities
Data from the NDVI only indicate greenness, which prevents us from unraveling the causal pathways between green places and health. We are developing a suite of measures to investigate these pathways, including accessibility of green space, type of vegetation, tree canopy cover, and related estimates of ecosystem services. Building on current work in Vancouver, we will also help to enhance NDVI with measures of green space access and quality by linking municipal data and applying quality appraisal with Google Street.