Table 1 The predictor variables used by the Random Forests algorithm to create a global prediction map for avian influenza virus in wild birds.
From: A global model of avian influenza prediction in wild birds: the importance of northern regions
Predictor variable | Details | VIS | Project source |
|---|---|---|---|
Annual precipitation (mm) | In mm; 30 arc-seconds, 1Â km spatial resolution | 100.0 | WorldClim[29] |
Mean temperature, June (°C) | In °C; 30 arc-seconds, 1 km spatial resolution | 85.2 | WorldClim |
Mean temperature, April (°C) | In °C; 30 arc-seconds, 1 km spatial resolution | 76.1 | WorldClim |
Precipitation of driest quarter (mm) | In mm; 30 arc-seconds, 1Â km spatial resolution | 68.4 | WorldClim |
Mean temperature, November (°C) | In °C; 30 arc-seconds, 1 km spatial resolution | 64.9 | WorldClim |
Precipitation seasonality | In mm; 30 arc-seconds, 1Â km spatial resolution | 63.1 | WorldClim |
Mean temperature of driest quarter (°C) | In °C; 30 arc-seconds, 1 km spatial resolution | 62.5 | WorldClim |
Annual mean temperature (°C) | In °C; 30 arc-seconds, 1 km spatial resolution | 54.8 | WorldClim |
Mean temperature, February (°C) | In °C; 30 arc-seconds, 1 km spatial resolution | 49.7 | WorldClim |
Mean temperature, January (°C) | In °C; 30 arc-seconds, 1 km spatial resolution | 45.7 | WorldClim |
Temperature seasonality | Standard deviation Ă— 100 | 45.0 | WorldClim |
Precipitation of wettest quarter (mm) | In mm; 30 arc-seconds, 1Â km spatial resolution | 42.9 | WorldClim |
Mean temperature, December (°C) | In °C; 30 arc-seconds, 1 km spatial resolution | 38.6 | WorldClim |
Maximum temperature of warmest month (°C) | In °C; 30 arc-seconds, 1 km spatial resolution | 38.0 | WorldClim |
Precipitation of driest month (mm) | In mm; 30 arc-seconds, 1Â km spatial resolution | 37.5 | WorldClim |
Mean temperature, October (°C) | In °C; 30 arc-seconds, 1 km spatial resolution | 36.1 | WorldClim |
Mean temperature, September (°C) | In °C; 30 arc-seconds, 1 km spatial resolution | 32.6 | WorldClim |
Precipitation of coldest quarter (mm) | In mm; 30 arc-seconds, 1Â km spatial resolution | 32.3 | WorldClim |
Population density (persons/km2) | Population density for 2010, 2.5’ resolution, persons/km2 | 29.3 | Gridded Popn of the World, v.3[30] |
Mean temperature of coldest quarter (°C) | In °C; 30 arc-seconds, 1 km spatial resolution | 28.4 | WorldClim |
Mean temperature, July (°C) | In °C; 30 arc-seconds, 1 km spatial resolution | 28.3 | WorldClim |
Isothermality (°C) | (Mean Diurnal Range/Temperature Annual Range); In °C; 30 arc-seconds, 1 km spatial resolution | 26.6 | WorldClim |
Mean temperature of wettest quarter (°C) | In °C; 30 arc-seconds, 1 km spatial resolution | 25.2 | WorldClim |
Mean diurnal range (°C) | In °C, (mean of monthly temperature(max – min)) | 24.3 | WorldClim |
Mean temperature, August (°C) | In °C; 30 arc-seconds, 1 km spatial resolution | 22.7 | WorldClim |
Mean temperature, March (°C) | In °C; 30 arc-seconds, 1 km spatial resolution | 21.0 | WorldClim |
Temperature annual range (°C) | In °C; 30 arc-seconds, 1 km spatial resolution | 18.4 | WorldClim |
Elevation (m) | In m; 30 arc-seconds, 1Â km spatial resolution | 18.3 | WorldClim |
Predicted pig density (per km2) | Animal density/km2; 3Â min of arc | 18.0 | Gridded livestock of the world[31] |
Mean temperature of warmest quarter (°C) | In °C; 30 arc-seconds, 1 km spatial resolution | 17.0 | WorldClim |
Precipitation of wettest month (mm) | In mm; 30 arc-seconds, 1Â km spatial resolution | 15.0 | WorldClim |
Distance from coast (m) | Calculated from coastline | 12.6 | Esri |
Precipitation of warmest quarter (mm) | In mm; 30 arc-seconds, 1Â km spatial resolution | 12.1 | WorldClim |
Minimum temperature of coldest month (°C) | In °C; 30 arc-seconds, 1 km spatial resolution | 11.2 | WorldClim |
Human footprint index | Percentage of relative human influence (0–100) | 10.4 | Last of the Wild[32] |
Distance from rivers, lakes, or wetlands | Calculated from combined large and small lake polygons, nd lakes and wetlands grid | 9.7 | Global Lakes and Wetlands Database[33] |
Slope | Calculated from elevation | 9.0 | Esri |
Human influence index | Summative index of human disturbance (0–72) | 8.8 | Last of the Wild[32] |
Predicted poultry density (per km2) | Animal density/km2; 3Â min of arc | 7.9 | Gridded livestock of the world[31] |
Aspect | positive degrees from 0 to 359.9, measured clockwise from north; calculated from slope | 6.7 | Esri |
Mean temperature, May (°C) | In °C; 30 arc-seconds, 1 km spatial resolution | 5.4 | WorldClim |