California Air Is Cleaner, but Troubles Remain

On many days, a hiker on the Temescal Ridge trail above the Pacific Ocean, 30 to 50 miles west of the San Gabriel Mountains, can trace the snowy ridges and the thin, brown lines of canyons with the naked eye. Three decades ago, an entire summer could pass before homeowners just five miles from the mountains could see the peaks.

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In the last half-century, the urgent need to scrub clean the filthiest air in the country has reshaped the region’s politics, turned obscure agencies into regulatory behemoths and made Los Angeles an international leader in its hard-won expertise.

But for all this achievement, success – consistently healthy air for all 16 million Southern Californians – remains out of reach.

The ozone pollution is improving but the region remains, along with Houston and the San Joaquin Valley in Central California, one of the worst three in the nation.

New York Times