It was the hottest summer on record around the world, so it may come as no surprise that New Jersey had a couple dozen days when the air was unhealthy to breathe.
With the start of fall yesterday, the state already had recorded 24 days when it failed to meet the national health-quality standard for ground-level ozone or smog — four days more than the previous summer.
This year’s health standard for smog, a pollutant that causes irritation and breathing problems for young and old, is more stringent than its predecessor. The new standard is 70 parts per billion compared with 75 ppb, the level first set back in 2008.
Given the tougher standard and hotter-than-normal summer, environmental officials said it is evidence that the state is making progress cleaning up its air quality.
“It speaks volume to the work we’ve been doing for years in addressing the sources of smog — automobiles and power plants,’’ said Larry Hajna, a spokesman for the state Department of Environmental Protection.
Environmentalists had a different perspective. “It’s still 24 days of the year when it is unhealthy for kids with asthma to walk outside,’’ said David Pringle, campaign director for Clean Water Action.
On those 24 days, the standard was exceeded at 69 stations around the state, an indication of how pervasive the problem remains.
New Jersey has never met the standard for ozone, a pollutant that forms in hot sunny weather when emissions from power plants, businesses, and vehicles “bake” to form smog, which blankets much of the state.
Since the Clean Air Act was enacted in 1980, the state has taken many steps to try to meet the standard, imposing the first-in-the nation auto-emissions inspection program, clamping down on pollution from power plants, and imposing stricter limits on some consumer products, including gasoline.
Nevertheless, complying with the standard has proven elusive, even when it was less stringent. In 2002, when the standard was 84 ppb, the state had 45 violations, which would have numbered 76 days if measured by today’s limit, according to Hajna.
For many years, industry and state officials have blamed pollution from other states that is blown into New Jersey from the west for being a major contributor to the problem.
‘’There has to be a level playing field where everyone does their equal share,’’ said Michael Egenton, executive vice president of the New Jersey State Chamber of Commerce, the longest serving member on the state’s Clean Air Council. “Our guys have done their part.’’
But others said the state will continue to have problems as the world warms and the climate changes because of greenhouse-gas emissions.
“Climate change is real. It is affecting our climate and our health,’’ said Jeff Tittel, director of the New Jersey Sierra Club. “We’re not doing enough about it, particularly about moving forward on plug-in vehicles.’’
The transportation sector accounts for about 40 percent of the emissions contributing to smog. Clean-energy advocates tout zero-emission vehicles, or electric cars, as crucial to achieving various clean-air goals.
In any event, climate change is going to make ozone alert days worse, predicted Doug O’Malley, director of Environment New Jersey. “And the Christie administration is asleep at the switch.’’
David Robinson, state climatologist, agreed. “With warmer summers, we should see more ozone danger,’’ he said. The trend appears likely to continue. Of the 11 warmest summers on record in New Jersey since 1895, nine have occurred since 1989, he said.