MAP GUIDE. Global Land Cover Characteristics Maps (USGS EROS) Summary

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1 MAP GUIDE Global Land Cover Characteristics Maps (USGS EROS) Global Ecosystems IGBP Land Cover USGS Land Use/Land Cover Simple Biosphere Model Simple Biosphere 2 Model Vegetation Lifeforms Biosphere Atmosphere Transfer Scheme Matthews Land Cover Summary What are they? TerraViva! provides a series of eight thematic maps representing land cover of the earth from different scientific perspectives. These maps comprise the Global Land Characteristics database (GLCC) and illustrate the distribution of earth surface materials or "land cover" over the entire globe. By exploring each map, you can identify at a glance the location and expanse of major ecological systems forests, grasslands, tundra, agricultural regions and deserts and examine their inter-relationships. As you move your cursor around on a map a small text box near the cursor displays the land cover classification at the cursor position. The gray status bars located just below the map display the name of the administrative unit, the land cover classification at the cursor position, and the geographic coordinates at the cursor position. Source of the TerraViva! Maps. The Global Land Cover Characteristics Data Base Version 2.0 (GLCC) is the most comprehensive representation of land cover for the entire globe. A primary data set identifying 96 land classes - Global Ecosystems forms the basis for seven additional GLCC data products: IGBP Land Cover, USGS Land Use/Land Cover, Simple Biosphere Model, Simple Biosphere 2 Model, Biosphere Atmosphere Transfer Scheme, Matthews Land Cover, and Vegetation Lifeform. Each product emphasizes different land cover features or inter-relates landforms to support specific scientific analyses. GLCC data sets are available from the NASA Land Distributed Active Archive Center at the USGS Eros Data Center in Sioux Falls, South Dakota. Each version is available in Goode Interrupted Homolosine at one kilometer and Geographic projection at thirty arc-seconds resolution. Why was GLCC created? The GLCC database was an international project undertaken by a number of organizations under the auspices of the International Geosphere- Biosphere Programme (IGBP) and NASA. The US Geological Survey EROS Data Center performed the technical task of creating the land cover map by interpreting space remote sensing data. GLCC was developed at the request of scientists interested in the study of global environmental change. These scientists believed that existing maps of land cover were inadequate to represent current conditions, and they sought an improved, updated map in order to properly model effects of climate change and other global environmental processes. Scientists continue to pursue improved representations of the Earth s biosphere and are now actively employing advanced sensors like Modis and Landsat.

2 How was GLCC constructed? The GLCC data set was derived from the National Oceanic and Space Administration (NOAA) Advanced Very High Resolution Radiometer (AVHRR) data collected daily over a 12-month period from April 1992 through March AVHRR is carried on NOAA's Polar Orbiting Environmental Satellite (POES) and its daily measurements reflect energy at each 1-km 2 location on the earth's surface. This daily data creates a time-series that reveals plant development patterns, called phenology, and other features such as onset, peak, and seasonal duration of vegetation greenness. These features relate to the amount of plant material, or biomass, produced. The accumulated vegetative material is referred to as "net primary productivity." Such features allow discrimination of various types of vegetation and other land covers. Scientists used statistical techniques to process the AVHRR signals, determining ninetysix land cover patterns based on a taxonomy established by J. Olson (1994). These 96 classes for the most part formed the basis for each of the eight GLCC map products. Each map is an interpretation suited to a specific scientific purpose as described later. How were the TerraViva! maps derived from the source data? The entire collection of eight GLCC products are available at full resolution. Since all versions are derived from the Global Ecosystems map, lossless compressions of greater than 100:1 were achieved, enabling instantaneous renderings when switching from one GLCC map to another.

3 What do the Colors Mean? The color codes of each map are described in the map legend and an explanation of the unique value of the map presented.

4 1. Global Ecosystems Global ecosystem categories were derived from those developed by J. Olson (1994) to represent global land cover patterns derived from coarse resolution remote sensing data for use in carbon cycle studies. The ninety six categories provide as broad a range of land cover types. 2. Land Cover (IGBP) Definitions of land cover classes are reproduced below from original IGBP working plans (from Belward, A. S., 1996). The legend employed was developed to meet the needs of IGBP projects, providing for a consistent and objective representation of significant landforms for all projects.

5 Unclassified: Land cover unknown Evergreen Needleleaf Forest: Lands dominated by trees with a percent canopy cover >60% and height exceeding 2 meters. Almost all trees remain green all year. Canopy is never without green foliage. Evergreen Broadleaf Forest: Lands dominated by trees with a percent canopy cover >60% and height exceeding 2 meters. Almost all trees remain green all year. Canopy is never without green foliage. Deciduous Needleleaf Forest: Lands dominated by trees with a percent canopy cover >60% and height exceeding 2 meters. Consists of seasonal needleleaf tree communities with an annual cycle of leaf-on and leaf-off periods. Deciduous Broadleaf Forest: Lands dominated by trees with a percent canopy cover >60% and height exceeding 2 meters. Consists of seasonal broadleaf tree communities with an annual cycle of leaf-on and leaf-off periods. Mixed Forest: Lands dominated by trees with a percent canopy cover >60% and height exceeding 2 meters. Consists of tree communities with interspersed mixtures or mosaics of the other four forest cover types. None of the forest types exceeds 60% of landscape. Closed Shrubland: Lands with woody vegetation less than 2 meters tall and with shrub canopy cover >60%. The shrub foliage can be either evergreen or deciduous. Open Shrubland: Lands with woody vegetation less than 2 meters tall and with shrub canopy cover between 10-60%. The shrub foliage can be either evergreen or deciduous. Woody Savanna: Lands with herbaceous and other understory systems, and with forest canopy cover between 30-60%. The forest cover height exceeds 2 meters. Savannas: Lands with herbaceous and other understory systems, and with forest canopy cover between 10-30%. The forest cover height exceeds 2 meters.

6 Grassland: Lands with herbaceous types of cover. Tree and shrub cover is less than 10%. Permanent Wetland: Lands with a permanent mixture of water and herbaceous or woody vegetation that cover extensive areas. The vegetation can be present in salt, brackish, or fresh water. Cropland: Lands covered with temporary crops followed by harvest and a bare soil period (e.g., single and multiple cropping systems). Note that perennial woody crops will be classified as the appropriate forest or shrub land cover type. Urban and Built-up: Land covered by buildings and other man-made structures. Note that this class will not be mapped from the AVHRR imagery but will be developed from the populated places layer that is part of the Digital Chart of the World (Danko, 1992) Cropland/Natural Vegetation Mosaic: Lands with a mosaic of croplands, forests, shrublands, and grasslands in which no one component comprises more than 60% of the landscape. Snow and Ice: Lands under snow and/or ice cover throughout the year. Barren: Lands with exposed soil, sand, rocks, or snow and never more than 10% vegetated cover during any time of the year. Water: Oceans, seas, lakes, reservoirs, and rivers, either fresh or saltwater. 3. Land Use/Land Cover (USGS) Definitions of land cover classes are reproduced below from original USGS working plans (from Anderson, James R., et al, 1976). The USGS Anderson system is a hierarchical system derived to support analysis from remote sensing, each level providing increasing levels of specificity. The colors categories used in this legend generally correspond to Anderson level 2.

7 Note: For comprehensive definitions see Anderson, James R. et all A Land Use and Land Cover Classification System For Use With Remote Sensor Data, Geological Survey Professional Paper 964, US Government Printing Office; and Global Land Cover Characteristics Data Base Version 2.0 Global Documentation, Appendix 3: USGS Land Use/Land Cover System Legend (Modified Level 2). Urban and Built-Up Land: Land areas of intensive use with much of the land covered by structures. Included in this category are cities, towns, villages, strip developments along highways, transportation, power, and communications facilities, and areas such as those occupied by mills, shopping centers, industrial and commercial complexes, and institutions that may, in some instances, be isolated from urban areas. Dryland Cropland and Pasture: The several components of Cropland and Pasture now used for agricultural statistics include: cropland harvested, including bush fruits; cultivated summer fallow and idle cropland; land on which crop failure occurs; cropland in soil-improvement grasses and legumes; cropland used only for pasture in rotation with crops; and pasture on land more or less permanently used for that purpose. Irrigated Cropland and Pasture: The several components of Cropland and Pasture now used for agricultural statistics include: cropland harvested, including bush fruits; cultivated summer fallow and idle cropland; land on which crop failure occurs; cropland in soil-improvement grasses and legumes; cropland used only for pasture in rotation with crops; and pasture on land more or less permanently used for that purpose.

8 Mixed Dryland/Irrigated Cropland and Pasture: Land areas consisting of a mixture or mosaic of Dryland and Irrigated Cropland and Pasture. Cropland/Grassland Mosaic: Land areas consisting of a mixture or mosaic of Croplands and Grasslands. Cropland/Woodland Mosaic: Land areas consisting of a mixture or mosaic of Croplands and Woodlands. Grassland: Lands dominated by naturally occurring grasses and forbs as well as those areas of actual rangeland which have been modified to include grasses and forbs as their principal cover, when the land is managed for rangeland purposes and not managed using practices typical of pastureland. Shrubland: Lands characterized by such xerophytic vegetative types with woody stems as big sagebrush, shadscale, greasewood, or creosotebush and also by the typical desert succulent xerophytes, such as the various forms of Cactus. Mixed Shrubland/Grassland: Areas with more than one-third intermixture of either herbaceous or shrub and brush rangeland species. Savanna: Further classification of Level II Rangeland. Deciduous Broadleaf Forest: Forested areas that have a predominance of deciduous broadleaf trees. Deciduous Needleleaf Forest: Forested areas that have a predominance of deciduous needleleaf trees. Evergreen Broadleaf Forest: Forested areas that have a predominance of broadleaved evergreens. Evergreen Needleleaf Forest: Forested areas that have a predominance of coniferous evergreens, commonly referred to or classified as softwoods. Mixed Forest: Forested areas where both evergreen and deciduous trees are growing and neither predominates. Water Bodies: Areas within the land mass that are persistently water covered, provided that, if linear, they are at least 1/8 mile (200m) wide and, if extended, cover at least 40 acres (16 hectares) including streams and canals, lakes, reservoirs, bays, and estuaries. Herbaceous Wetland: Lands that are dominated by wetland herbaceous vegetation or are non-vegetated. These wetlands include tidal and nontidal fresh, brackish, and salt marshes and non-vegetated flats and also freshwater meadows, wet prairies, and open bogs. Wooded Wetland: Lands dominated by woody vegetation; seasonally flooded bottomland hardwoods, mangrove swamps, shrub swamps, and wooded swamps including those around bogs. Barren or Sparsely Vegetated: Land with limited ability to support life. Herbaceous Tundra: Lands composed of various sedges, grasses, forbs, lichens, and mosses, all of which lack woody stems.

9 Wooded Tundra: Lands consisting of the various woody shrubs and brushy thickets found in the tundra environments. Mixed Tundra: Lands where a mixture of the Level II Tundra occurrences exist where any particular type occupies less than two-thirds of the area of the mapping unit. Bare Ground Tundra: The Bare Ground Tundra category is intended for those Tundra occurrences which are less than one third vegetated. It usually consists of sites visually dominated by considerable areas of exposed bare rock, sand, or gravel interspersed with low herbaceous and shrubby plants. Snow or Ice: Lands with a perennial cover of either snow or ice, because of a combination of environmental factors that cause these features to survive the summer melting season. Includes Perennial Snowfields and Glaciers. 4. Simple Biosphere (SiB) SiB was developed by Sellers (1996) specifically to support land-atmosphere interactions in climate models. SiB land cover categories attempt to capture the range of such interactions assumed to be important in determining various energy, momentum and mass balance terms in climate models. Other uses beyond such modeling are not recommended. 5. Simple Biosphere 2 SiB 2 is a refinement of SiB using fewer classes to simplify modeling of land-atmosphere interactions. SiB2 is not intended for uses other than in such models.

10 6. Vegetation Lifeforms Vegetation Lifeforms is a legend developed by Running (1994a) for parametization of biogeocemical and net primary productivity models and presents the simplest categorixzation of the earth s surface in terms of basic vegetation types. The Running strategy is based on definitions of three canopy components: vegetation structure (termed above ground biomass by Running), leaf longevity, and leaf type. Vegetation structure defines whether the vegetation retains perennial or annual above ground biomass, an issue for seasonal climate and carbonbalance modeling. It is also a determinant of the surface roughness length parameter that climate models require for energy and momentum transfer equations. Leaf longevity (evergreen versus deciduous canopy) is a critical variable in carbon cycle dynamics of vegetation, and affects seasonal albedo and energy transfer characteristics of the land surface. Leaf longevity indicates whether a plant annually must completely regrow its canopy, or a portion of it, with inferred consequences to carbon partitioning, leaf litterfall dynamics, and soil carbon. Leaf type (needleleaf, broadleaf, and grass) affects gas exchange characteristics. 7. Biosphere Atmosphere Transfer Scheme (BATS) The BATS landform categories was created by Dickenson (1986) and modified by Olson (1994) to support land-atmosphere modeling. It is used as a land surface parameterization scheme for

11 general circulation models or mesoscale meteorological models. The Olson revision provided for better representation of mixed interrupted woodlands. 8. Matthews Land Cover The Matthews Land Cover legend is modeled after a taxonomy developed by E. Matthews (1983). This legend was developed for use in parameterizing land-atmosphere interactions within early generations of global climate models and attempts to describe potential vegetation.

12 Information Mode Information Mode enables access to Profiles. A left click on the map will display the Profile window for the country located at the cursor position, using the default database. Sources and Acknowledgements ISCIENCES obtained the GLCC from the USGS EROS Data Center Earth Observation System database. The efforts of the IGBP, NASA, the USGS EDC and many others resulted in the creation of this valuable global database. ISCIENCES presents it to users of our products in a viewable and easy to interpret format. References Anderson, James R., Hardy, Ernest E., Roach, John T., and Witmer, Richard E A Land Use and Land Cover Classification System For Use With Remote Sensor Data. Geological Survey Professional Paper 964, US Government Printing Office.

13 Belward, A. S (editor). The IGBP-DIS Global 1 km Land Cover Data Set (DISCover): Proposal and Implementation Plans. IGBP-DIS Working Paper No. 13, IGBP-DIS Office. Toulouse, France. Global Land Cover Characteristics Data Base Version 2.0. Land Processes Distributed Active Archive Center. Danko, D. M The digital chart of the world. Geoinfosystems 2: Dickinson, R.E., Henderson-Sellers, A., Kennedy, P.J., and Wilson, M.F Biosphere-Atmosphere Transfer Scheme (BATS) for the NCAR Community Climate Model. NCAR Technical Note NCAR/TN-275+STR, Boulder, CO. Loveland, T. R., Merchant, J. W., Ohlen, D. O. and Brown, J. F Development of a Land-cover Characteristics Database for the Conterminous US: Photogrammetric Engineering and Remote Sensing 57(11): Loveland, T. R., Zhu, Z., Ohlen, D. O., Brown, J. F., Reed, B. C., and Yang, L An Analysis of the IGBP Global Land Cover Characterization Process. Photogrammetric Engineering and Remote Sensing (in press). Loveland, T. R., Reed, B. C., Brown, J. F., Ohlen, D. O., Zhu, J, Yang, L., and Merchant, J. W Development of a Global Land Cover Characteristics Database and IGBP DIS Cover from 1-km AVHRR Data. International Journal of Remote Sensing. Loveland, T. R., Brown, J. F Impacts of Land Cover Legends on Global Land Cover Patterns, ASRS Pecora Symposium Proceedings. Matthews, E Global Vegetation and Land Use: New High Resolution Data Bases for Limited Studies. Journal of Climatology and Applied Meteorology 22: Olson, J.S Global Ecosystems Framework: Definitions. USGS EROS Data Center Internal Report, Sioux Falls, SD, 37 p. Olson, J.S. and Watts, J.A Major World Ecosystem Complex Map. Oak Ridge, TN: Oak Ridge National Laboratory. Sellers, P.J., Mintz, Y., Sud, Y.C., and Dalcher, A A simple biosphere model (SiB) for use within general circulation models. Journal of Atmospheric Science 43: Sellers, P.J., Los, S.O., Tucker, C.J., Justice, C.O., Dazlich, D.A., Collatz, G.J., and Randall, D.A A revised land surface parameterization (SiB2) for atmospheric GCMs - part II: the generation of global fields of terrestrial biophysical parameters from satellite data. Journal of Climate 9: