--- ---  # Worst Smog in Years Hits Southern California  by [Justin Worland](https://time.com/author/justin-worland/)  ## Justin Worland Senior Correspondent Aug 11, 2016 6:52 PM UTC  Walter Bibikow—Getty Images/AWL Images RM  by [Justin Worland](https://time.com/author/justin-worland/)  ## Justin Worland Senior Correspondent Aug 11, 2016 6:52 PM UTC The worst smog in years has inundated Southern California this summer, driving people to hospitals and health clinics for treatment of respiratory illness, according to a Los Angeles _Times_ [report](http://www.latimes.com/local/lanow/la-me-ln-summer-smog-20160805-snap-story.html). Some of the warmest weather of all time, compounded by stagnant winds, has worsened the problem, the [report](http://www.latimes.com/local/lanow/la-me-ln-summer-smog-20160805-snap-story.html) said. Ozone levels have topped federal standards on 91 days this year, compared to 67 days last year. **Read More**: [Global Air Pollution Is on the Rise Despite Decades of Efforts to Stop It](http://time.com/4326721/air-pollution-poor-cities/) Policymakers in developed countries have implemented a number of regulations to improve air quality in recent decades, leading to a dramatic decline in air pollution. But that progress has slipped in some places in recent years for a variety of different reasons. Rising temperatures in Southern California—due to climate change, El Niño and other factors—has heated hydrocarbon and nitrogen oxide pollution from vehicles, leading to smog. Storms typically clear the air, but they have been in short supply during the state’s [drought](http://time.com/3621246/california-drought-study/). California is not the only place with an [air pollution problem](http://time.com/4219575/air-pollution-deaths/). In many [European cities](http://London Air Pollution Became a Major Issue in Its Mayoral Race), a rise in diesel vehicles has contributed to high levels of air pollution. Developing countries like India and [China](http://time.com/4155365/china-red-alert-smog/) continue to experience high levels of air pollution as a result of rapid industrial growth and weak regulation. Smog: Los Angeles Air Pollution Rises With Heat, Weather ```json [{"@context":"https://schema.org","@type":"NewsArticle","@id":"https://time.com/4448813/worst-smog-in-years-southern-california/","mainEntityOfPage":{"@type":"WebPage","@id":"https://time.com/4448813/worst-smog-in-years-southern-california/"},"headline":"Worst Smog in Years Hits Southern California","datePublished":"2016-08-11T18:52:17.000Z","dateModified":"2026-02-22T23:56:01.595Z","description":"Conditions have people seeking treatment for respiratory illness","url":"https://time.com/4448813/worst-smog-in-years-southern-california/","keywords":["Environment"],"thumbnailUrl":"https://static.time.com/v3/assets/bltea6093859af6183b/blt1ed83348cf62e3dc/6988a2115f570f237bb222b7/los-angeles-air-pollution.jpeg?branch=production&width=1200&quality=75&auto=webp&crop=1200:675&height=675","author":[{"@type":"Person","name":"Justin Worland","jobTitle":"Senior Correspondent","url":"https://time.com/author/justin-worland/"}],"articleSection":"Science","image":[{"@type":"ImageObject","url":"https://static.time.com/v3/assets/bltea6093859af6183b/blt1ed83348cf62e3dc/6988a2115f570f237bb222b7/los-angeles-air-pollution.jpeg?branch=production&width=1200&quality=75&auto=webp&crop=1200:675&height=675","width":1200,"height":675,"headline":"los angeles smog air pollution","caption":"los angeles smog air pollution","creditText":"Walter Bibikow—Getty Images/AWL Images RM","representativeOfPage":true}],"publisher":{"@type":"Organization","name":"Time","url":"https://time.com/","logo":{"@type":"ImageObject","url":"https://time.com/images/logo.png","width":528,"height":156},"foundingDate":"March 3, 1923","sameAs":["https://www.facebook.com/time","https://www.instagram.com/time/?hl=en","https://twitter.com/time","https://www.pinterest.com/timemagazine"]}},{"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"item":{"@id":"/section/science/","name":"Science"}},{"@type":"ListItem","position":2,"item":{"@id":"/tag/environment/","name":"Environment"}},{"@type":"ListItem","position":3,"item":{"@id":"https://time.com/4448813/worst-smog-in-years-southern-california/","name":"Worst Smog in Years Hits Southern California"}}]}] ```