A world map shows high (dark blue) urban population in America, Australia, parts of the Middle East, Southeast Asia; moderate (blue) in parts of Africa, Asia, and Eastern Europe; low (light blue) in Central/South Asia, and Sub-Saharan Africa.
Class | Rank | Percent | Major Iron-Producing Areas in North America | Oil Shale or Tar Sands | Lightning Frequency | <0.1 flashes/km²/year | 0.1 flashes/km²/year | 0.2 flashes/km²/year | 0.4 flashes/km²/year | 0.6 flashes/km²/year | 0.8 flashes/km²/year | 1 flash/km²/year | 2 flashes/km²/year | 4 flashes/km²/year | 6 flashes/km²/year | 8 flashes/km²/year | 10 flashes/km²/year | 20 flashes/km²/year | 30 flashes/km²/year | -36 to -41°C | -30 to -35°C | -24 to -29°C | -18 to -23°C | -12 to -17°C | -6 to -11°C | 0 to -5°C | 0 to 2°C | 3 to 5°C | 6 to 8°C | 9 to 11°C | 12 to 14°C | 15 to 17°C | 18 to 20°C | 21 to 23°C | 24 to 26°C | 27 to 29°C | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2.52% | 11.5% | 24.4% | 16.4% | 8.63% | 6.27% | 9.50% | 4.67% | 3.58% | 14.1% | 25.7% | 10.1% | 11.3% | 14.8% | 42.6% | 30.6% | 47.1% | 14.7% | 34.5% | 21.4% | 15.2% | 21.7% | 17.5% | 23.1% | 15.3% | 33.6% | 16.9% | 13.3% | 8.73% | 8.38% | 5.23% | 17.2% | 8.69% | 7.14% | ||||