| Share | Phrase |
|---|
| 15.04% | environmental [natural phenomenon] condition |
| 8.77% | environmental [natural phenomenon] shield |
| 8.27% | environmental [natural phenomenon] agency |
| 7.50% | environmental [natural phenomenon] concern |
| 5.47% | environmental [natural phenomenon] protection |
| 5.47% | environmental [natural phenomenon] system |
| 4.30% | environmental [natural phenomenon] pollution |
| 4.07% | environmental [natural phenomenon] regulation |
| 3.94% | environmental [natural phenomenon] problem |
| 3.68% | environmental [natural phenomenon] parameter |
| 2.98% | environmental [natural phenomenon] value |
| 2.79% | environmental [natural phenomenon] effect |
| 2.67% | environmental [natural phenomenon] sealing |
| 2.63% | environmental [natural phenomenon] temperature |
| 2.54% | environmental [natural phenomenon] hazard |
| 2.41% | environmental [natural phenomenon] article |
| 2.29% | environmental [natural phenomenon] view |
| 1.78% | environmental [natural phenomenon] impact |
| 1.76% | environmental [natural phenomenon] change |
| 1.43% | environmental [natural phenomenon] factor |
| 1.14% | environmental [natural phenomenon] quality |
| 1.14% | environmental [natural phenomenon] reason |
| 1.14% | environmental [natural phenomenon] standard |
| 1.01% | environmental [natural phenomenon] damage |
| 1.01% | environmental [natural phenomenon] noise |
| 0.88% | environmental [natural phenomenon] control |
| 0.77% | environmental [natural phenomenon] contamination |
| 0.76% | environmental [natural phenomenon] consideration |
| 0.76% | environmental [natural phenomenon] influence |
| 0.76% | environmental [natural phenomenon] requirement |
| 0.70% | environmental [natural phenomenon] means |