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Plotting Categorical Data

Vegetation and landuse classifications are examples of categorical data. Each classification is unique.
vegland_1.ncl: The following IGBP vegetation classification is derived from the CERES 10-min Map Land Classification.

Surface types 1 - 17 correspond to those defined by IGBP (International Geosphere Biosphere Programme). The last 3 surface types were defined for CERES. Surface type 18, Tundra, occurs when a location has an IGBP surface type of 16 (bare soil and rocks) and the Olson vegetation map identifies the same location as Tundra. Fresh snow, number 19, and sea ice, number 20 are not permanent surface types. They are obtained daily from the National Snow and Ice Data Center. The IGBP surface type for snow and ice number 15, is for permanent snow and ice. It does not change with time The IGBPa_1198.map does NOT show surface types 19 and 20 as these change daily. THIS MAP IS STATIC (i.e., doesn't change with time). For surface type maps that change with time, see MODIS Land products.