At 30-meter resolution, this land cover is one of the finest available. The University of Maryland teamed up with the USGS to lace together its circa 2010 tree cover, bare ground and persistent surface water.
Using Landsat 7 ETM+ data, its most impressive attribute is its tree cover canopydescribed as percentage per output grid cell. This canopy cover is used to weigh in global forest extent, loss, and gain from 2000 to 2012 such as this Global Forest Change webmap.
- Climate Change Initiative (CCI) Land Cover V2
At 300 meter resolution, ENVISAT MERIS sensor is the biggest contributor to the 3 epoch land cover maps (1998-02, 2003-07 and 2008-12) of the CCI Land Cover V2.
With all the other land cover classification, it’s based on image classification algorithms.
- MCD12Q1 0.5 km MODIS-based Global Land Cover Climatology
The 500-meter MODIS Land Cover Maps (17 land cover classes) describes the dominant class based on a 10 year span (2001-2010).
- USGS – Global Land Cover Characterization (GLCC)
GLCC is based on one-year Advanced Very High Resolution Radiometer (AVHRR) using an unsupervised image classification approach. Based on land area occupied, GLCC reaches a 66.9% accuracy. When the observer can’t deduce a pixel as a “true” cover, this majority rule accuracy has an accuracy even higher at 78.7℅ throwing out those sites.
GLCC is being used in a range of environmental modeling applications including the Goddard Earth Observing System Model V5 (GEOS-5).
These 30-meter resolution land cover maps show global distribution of 10 major land cover classes: water bodies, wetland, artificial surfaces, cultivated land, permanent snow and ice, forests, grasslands, shrubland, bare land and tundra.
It took over 10,000 Landsat satellite images to cover the entire Earth at 30 m resolution. This land cover uses pixel- and object-based methods and each class is identified in a prioritized sequence. At 8 selected areas, it achieves an overall classification accuracy of 80%.
- UN FAO Global Land Cover Network (GLC-SHARE)
The focus for the FAO’s GLC SHARE land cover is land management. This is reflected particularly in some of its classes – cropland, grassland, bare soil and mangroves. It includes artificial surfaces, water bodies, snow, treed, shrubs, herbaceous and sparse vegetation.
It’s coarse at today’s standards being a bit sharper than 1km grid cells. Further, it has an accuracy of about 80% with 1087 validation sites.
Its primary use is for better understanding land management so we’d expect better results in agricultural areas.
- Land Cover Type Yearly L3 Global 0.05Deg CMG
The Climate Modeling Grid has the same roots as MCD12Q1 using the same supervised classification-tree algorithm. This data set is available to download from the USGS Earth Explorer.
Although it generates the same 17-classes defined by the International Geosphere Biosphere Programme, it’s at a much lower spatial resolution (0.05°).
Terrapop contains a variety of existing global land cover data sets from the already mentioned 23-class ESA GLC and MODIS 1km.
On top of that, it includes a very coarse agricultural lands classification circa 2000 at 10km derived from the Global Landscapes Initiative. This contains harvested area and yield of 175 crops to better understand agricultural supply and demand.