Selected National Air Pollutant Emissions: 1970 to 2005
(In thousands of tons, except as indicated.)
The amount of various pollutants emitted into the air has fallen significantly between 1970 and 2005.
| Pollutant | 1970 (unless indicated) | 2005 |
|---|---|---|
| PM-10 | 12,184 | 2,258 |
| PM-10, misc. | 37,736 (1985) | 14,479 |
| PM-2.5 | 2,326 (1990) | 1,297 |
| PM-2.5, misc. | 5,233 (1990) | 1,660 |
| Sulfur dioxide | 31,218 | 14,709 |
| Nitrogen dioxide | 26,883 | 18,878 |
| Volatile organic compounds | 34,659 | 18,925 |
| Carbon monoxide | 204,043 | 106,843 |
| Lead (tons) | 220,869 | (NA) |
(Source)
These are very good average data in order to determine air quality differences over time. However, I wonder what would be the global differences, which might pinpoint sources(which may seem obvious) and exonerate those who are to blame for global air quality. After all, air emitted from Japan can be detected three to five days later in England. Good post.