Acid Rain
United StatesPhysical EnvironmentAverage acidity of precipitation in the United States. Lower pH values represent greater acidity.
Geosystems: Intro to Physical Geography
A map shows the p H levels of acid rain in the U.S. States like Ohio and Pennsylvania have the lowest p H levels (4.50 to 4.59 p H, black). States like Arizona and Nevada show the highest p H levels (greater than or equals 5.30 p H, light yellow).
4.50–4.59 pH | 4.60–4.69 pH | 4.70–4.79 pH | 4.80–4.89 pH | 4.90–4.99 pH | 5.00–5.09 pH | 5.10–5.19 pH | 5.20–5.29 pH | ≥5.30 pH | Class | Rank | Percent | Class | Rank | Percent | 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 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 4.29% | 14.4% | 23.8% | 24.2% | 18.5% | 16.1% | 11.6% | 6.63% | 81.6% | 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% | |||||||