We have some relatively positive news to report about smog problems around the nation in June.
Things are generally better than a year ago. In June air pollution monitors recorded unhealthful levels of smog an estimated 660 times, compared to about 1037 times in June 2006 and 950 in June 2005. (These are unofficial readings from state-run monitors recorded by our volunteers.)
Some of the improvements appear to be due to rains in Texas which washed some of the ozone away. Even so, it is heartening to see a long-term trend of improvement which we think can be ascribed to tougher pollution controls on electric power plants, cars and gasoline.
Interestingly, unhealthful smog levels were recorded in several states where that’s a rarity – Minnesota, Iowa and Kansas. Perhaps it’s because of the increased use of smog-forming ethanol in gasoline.
Please keep in mind that these statistics pertain to the 8-hour ozone standard set in 1997. The US EPA recently proposed tougher standards. And EPA’s science advisers believe the standards should be even stronger. So the real problem is actually worse than that described here.
A few quick statistics:
Unhealthful levels of smog (based on the 1997 standards) were recorded in 36 states plus the District of Columbia in June. See list below.
The highest single-hour smog reading (157 parts per billion) was recorded June 4 in the Houston area. San Bernardino County in California retains the dubious distinction of being America’s smoggiest area.
Here is the list of states with smog problems in June:
District of Columbia