| Similarity | Rank | |
|---|---|---|
| air_pollution | 0.684 | 13199 |
| pollution | 0.681 | 4581 |
| water_pollution | 0.678 | 34005 |
| pollutant | 0.660 | 14162 |
| pollution_from | 0.659 | 77604 |
| the_greenhouse_effect | 0.657 | 87706 |
| greenhouse_gas | 0.652 | 18514 |
| global_warming | 0.647 | 5979 |
| sulfur_dioxide | 0.645 | 93673 |
| smog | 0.644 | 39059 |
| air_pollutant | 0.642 | 77087 |
| nitrogen_oxide | 0.639 | 78932 |
| eutrophication | 0.629 | 69479 |
| dioxin | 0.603 | 55824 |
| mercury | 0.598 | 12741 |
| environmental_pollution | 0.593 | 52695 |
| anthropogenic | 0.593 | 94954 |
| carbon_dioxide_emission | 0.592 | 61386 |
| soot | 0.591 | 42732 |
| ozone | 0.589 | 18722 |
| acidification | 0.586 | 76521 |
| global_climate_change | 0.582 | 29854 |
| particulate_matter | 0.580 | 54856 |
| greenhouse_gas_emission | 0.573 | 18703 |
| air_quality | 0.571 | 15064 |