Heiskanen, J (2008). Evaluation of global land cover data sets over the tundra-taiga transition zone in northernmost Finland. INTERNATIONAL JOURNAL OF REMOTE SENSING, 29(13), 3727-3751.
The remote sensing-based continental to global scale land cover data sets provide several land cover depictions over the circumpolar tundra-taiga transition zone. The aim of this study was to evaluate three data sets in northernmost Finland: the Global Land Cover 2000 Northern Eurasia map (GLC2000-NE), the MODIS global land cover map (MODIS-IGBP) and the tree cover layer of the MODIS vegetation continuous fields product (MODIS-VCF). The data sets were first compared both visually and statistically to biotope inventory data including tree cover, height, species composition and shrub cover information as continuous variables. The agreement with reference data was poor because the classifications do not correspond to the class descriptions. The MODIS-VCF tree cover overestimates the tree cover in the low values and underestimates it in the high values. The agreement was relatively good when the global data sets were aggregated to a forest-non-forest level and compared to the Finnish CORINE Land Cover 2000 map over a larger area. However, the inaccurate mapping of the deciduous broadleaf forests and mires reduced the agreement at the forest-non-forest level. The vegetation transitions are difficult to map using low-resolution satellite data and further improvements to the land cover characterization over the tundra-taiga transition zone are required.