Landsat/Landsat NDVI Trend (1984–2012)
This research used a nominal peak greenness period, July 1 to August 31, to accommodate tundra of all regions for Landsat data selection. We only considered the terrain-corrected scenes, excluding scenes that have cloud cover more than 80%. As a result, a total of 87,762 Landsat scenes over 1271 Path/Row locations were selected from 1984-2012. Of these, 63% were from Landsat-5, as Landsat-5 provided the only data source for 1984-1998 and continued to acquire data until 2011. This work aims to provide a spatially complete view of the vegetation greenness change for all of Canada and Alaska by calculating per-pixel NDVI trend from all available 1984-2012 peak-summer Landsat-5 and -7 surface reflectance data.