Earth's land cover classification, 2003. Produced using data obtained during 2003 from the MODIS instrument on NASA's Terra satellite, this map shows the Earth's surface divided into 17 different types of land cover. These include: water (dark blue), snow and ice (white), barren areas (grey), forests (shades of green), savannas (bright yellow), grasslands (light brown), wetlands (light blue), crops (light yellow), and urban areas (red). The map was produced by combining satellite and land-based data using a computer algorithm to improve on previous land cover maps. Maps such as this are used in climate change models, and also to track changes such as urban growth, desertification and deforestation.