Ecosystems
The natural ecosystems of the Earth in reality just the parts of the planet that aren't actively managed by humans, as no corner of our world has been unaffected by our presence here. No system (climate, nutrient transport, water…) has avoided modification by the presence of man. Recently this knowledge has reached public awareness via the evening news as climate change, otherwise known by the less-accurate title of global warming.
Annual Total Precipitation
Description: The total amount of precipitation to fall in one gridcell during one year.
Source: CRU 0.5 Degree Dataset, New et al.(1998)
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View Dataset InformationAverage Annual Relative Humidity
Description: The average relative humidity of each grid cell over one year.
Source: CRU 0.5 Degree Dataset, New et al.(1998)
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Average Annual Temperature
Description: The average temperature of a gridcell over one year.
Source: CRU 0.5 Degree Dataset, New et al.(1998)
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Average Temperature (DJF)
Description: The average gridcell temerature during December, January, and February.
Source: CRU 0.5 Degree Dataset, New et al.(1998)
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Average Temperature (JJA)
Description: The average gridcell temperature during June, July, and August.
Source: CRU 0.5 Degree Dataset, New et al.(1998)
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Average Temperature (MAM)
Description: The average gricell temperature during March, April and May
Source: CRU 0.5 Degree Dataset, New et al.(1998)
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Average Temperature (SON)
Description: The average gridcell temperature during September, October, and November
Source: CRU 0.5 Degree Dataset, New et al.(1998)
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Evapotranspiration
Description: The amount of water removed from a gridcell through the processes of evaporation and transpiration.
Source: Willmott and Matsuura (2001)
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Growing Degree Days
Description: The total number of growing degree days (based on a 5C base temperature) in each gridcell over one year.
Source: CRU 0.5 Degree Dataset, New et al.(1998)
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Lakes and Wetlands
Description: The extent of lakes and wetlands of various categories across the globe.
Source: Lehner and Döll (2001)
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Net Primary Productivity
Description: The total net primary productivity (NPP) in each gridcell over one year.
Source: Foley et al. (1996), Kucharik et al. (2000)
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Potential Evapotranspiration
Description: Assuming no limiting factors, the amount of water that could be removed from the gridcell through evaporation and transpiration.
Source: Willmott and Matsuura (2001)
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Potential Vegetation
Description: The land cover type that would exist in a gridcell had humans not interfered.
Source: Ramankutty and Foley (1999)
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Snow Depth
Description: The average annual snow depth in each grid cell.
Source: Willmott and Matsuura (2001)
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Soil Moisture
Description: The average amount of water in the soil of a grid cell.
Source: Willmott and Matsuura (2001)
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Soil Organic Carbon
Description: The total mass of soil carbon (to one meter) contained in a gridcell.
Source: IGBP-DIS (1998)
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Soil pH
Description: The pH of the soil in a gridcell.
Source: IGBP-DIS (1998)
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Topography
Description: The elevation above sea level of each gridcell.
Source: NOAA TerrainBase
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