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Circumpolar Arctic AVHRR NDVI Map
The normalized difference vegetation index (NDVI) is a measure of greenness. NDVI was calculated as: NDVI = (NIR - R) / (NIR + R), where NIR is the spectral reflectance in the... -
Circumpolar Arctic AVHRR False Color-Infrared (CIR) Map
Advanced Very High Resolution Radiometer (AVHRR) data were obtained from the USGS Global AVHRR 10-day composite data. (http://edcdaac.usgs.gov/1KM/1kmhomepage.asp) (Markon et... -
Circumpolar Landscape Age Map (Raynolds et al. 2008)
The landscape age map shows the length of time (in thousands of years) that Arctic landscapes have been available for plant colonization and the development of plant communities... -
Circumpolar Arctic Elevation Map
Elevation strongly influences soil moisture and patterns of tundra plant communities. Areas less than 100 m above sea level were separated to show low-elevation plains. Areas... -
Circumpolar Arctic Bioclimate Subzones
A fundamental problem for the CAVM is how to characterize the transitions in vegetation that occur across the roughly 10 °C mean July temperature gradient from the tree line to... -
Circumpolar Arctic Landscape Map
The landscape map was derived from topographic data, regional physiographic maps, and visual interpretation of the AVHRR false-CIR image. Landscape codes were assigned to each... -
Circumpolar Arctic Vegetation Map (CAVM Team 2003)
The Circumpolar Arctic Vegetation Map (CAVM) is a geoecological map of the entire Arctic with a unified legend. It is the first vegetation map of an entire global biome at a... -
Circumpolar Arctic Lake Cover Map
Lake cover strongly affects the reflectance of the land surface over large areas of the Arctic, and was useful for identifying extensive wetlands. Lake cover was based on the... -
Circumpolar Arctic Biomass Trend 1982-2010 (Epstein et al. 2012)
Trend in Arctic biomass was calculated from a linear regression of biomass values for all years 1982-2010 (Epstein et al 2012). Pixels with significant trends (p < 0.05) were... -
Circumpolar Arctic AVHRR Summer Warmth Index 1982-2003 (Raynolds et al. 2008)
This data set was calculated from monthly AVHRR thermal infrared data (Comiso 2003). Summer Warmth Index (SWI) is the sum of monthly mean temperatures above 0 degrees Celsius.... -
Circumpolar Arctic Biomass (Raynolds et al 2012)
This map portrays an estimate of above ground plant biomass for the tundra biome based on trans-Arctic field data and AVHRR NDVI (Raynolds et al. 2012). Aboveground phytomass... -
Circumpolar Arctic Floristic Provinces Map
Floristic sectors characterize the considerable east-west floristic variation within the subzones. The more northern Arctic bioclimate subzones have a relatively consistent core... -
Circumpolar Arctic AVHRR NDVI Trend 1982-2008 (Bhatt et al. 2010)
The normalized difference vegetation index (NDVI) is a measure of greenness. NDVI was calculated as: NDVI = (NIR - R) / (NIR + R), where NIR is the spectral reflectance in the... -
Circumpolar Arctic Substrate pH
Differences in substrate chemistry have important effects on dominant plant communities. Some of the most important effects are related to soil pH, which governs the... -
Circumpolar Arctic Vegetation Map (Vegetation Layer)
Mapped polygons at 1:7.5 million scale contain many vegetation types. The map portrays the zonal vegetation within each mapped polygon. Zonal sites are areas where the... -
Circumpolar Arctic Coastline and Treeline Map
The map extent is the Arctic, defined as the Arctic Bioclimate Zone, the area of the Earth with tundra vegetation and an Arctic climate and Arctic flora. It excludes tundra...
