A few weeks ago I got an e-mail from someone at my department (directed to all people at the department) that the GlobeLand30 dataset had become freely available. I’ve been looking for reliable land cover data for my study area since I started my project, and so far I’ve not found anything that has been able to satisfy me. The MODIS land cover product had classified most of the Duhok governorate as shrubland or something (can’t remember exactly what it was but it was not correct).
This dataset has a spatial resolution of 30 meters (!) and covers land areas between 80 degrees N and 80 degrees S. It consist of ten land cover types: cultivated land, forest, grassland, shrubland, wetland, water bodies, tundra, artificial surfactes, bare land, permanent show and ice. The classification is based on data from different data sources, for the year 2010 (+/- 1 year). These data include Landsat TM and ETM+ images, HJ-1 satellite images (a Chinese RS satellite), and ancilliary data such as regional and national land cover maps, MODIS NDVI data and global elevation data.
I downloaded the tile covering the Duhok governorate and decided to compare it with my own validation data from 2013. I have given the symbols of my truth data colors corresponding to the colors of the GlobeLand30 classification. You can see that the classification corresponds quite well! I would of course need to do an accuracy assessment of the data to check to what extent it is accurate, but it does look good.
Purple – Cultivated land
Light Green – Grasslands
Dark Green – Forest/Woodland
Red – Artificial surfaces
Blue – Water