We found other first-hand testimony. Char Miller, a professor of environmental analysis at Pomona Co

Now, what you ll hear from the special interests and their allies in Congress is that (my climate change plan) will kill jobs and crush the economy and basically end American free-enterprise as we know it, Obama said. And the reason I know you ll hear those things is because that s what they said every time America sets clear rules and better standards for our air and our water and our children s health.
And every time they ve been wrong, Obama continued. when I was going to school in 1979, 1980 in Los Angeles, there were days where folks couldn t go outside -- and the sunsets were spectacular -- because of all the pollution in the air.
At the time when we passed the Clean Air Act, to try to get rid of some of this smog, some of the same doomsayers were saying, New pollution standards will decimate the auto industry. Guess what? It didn t happen. Our air got cleaner.
We ll start with some background on smog. The smog predominant in Los Angeles -- formally known as photochemical smog -- is created when light reacts with motor vehicle and industrial emissions to form ground-level ozone. This ozone can make it difficult to breathe, causing asthma attacks and lung inflammation, as well as making eyes itchy and watery.
In the United States, at least, Los Angeles has been ground zero for smog for decades, due to its heavy automobile usage, its industrial base and the presence of mountains and valleys, which prevent polluted air from floating elsewhere. Los Angeles smog emerged in the 1940s and worsened from the 1950s to the 1970s. It got so bad in October 1954 that the city virtually shut down for the entire month (and gas masks were common, as the photograph below illustrates). Smog became so closely identified with Los Angeles that smog in a can became a popular gag gift.
Today, Los Angeles still has smog -- in April 2013, the American Lung Association ranked L.A. first in the nation travel agents india for ozone pollution, as well as fourth for particulate pollution such as dust and soot. But concerted environmental efforts have reduced the extent of the problem significantly.
In rising order of seriousness, smog alerts for southern California travel agents india start with health advisories and move upwards to stage 1, stage 2 and stage 3. The last stage 3 smog alert came in 1974 -- so long ago that Ronald travel agents india Reagan was still governor. The last stage 2 alert came in 1988, and there has been only one stage 1 alert since 1998 (it came in 2003).
Peak ozone levels in southern California today are roughly one-third of what they were in the late 1970s, travel agents india due to aggressive and innovative air pollution controls here, said Sam Atwood, a spokesman for the South Coast Air Quality Management District, the air-pollution travel agents india control agency for Los Angeles, Orange County and portions travel agents india of Riverside and San Bernardino counties.
So what would Obama have experienced when he was a student at Occidental, the college he attended before transferring to Columbia University for his junior and senior year? We can approximate the impact based on statistical and anecdotal travel agents india evidence.
According to South Coast Air Quality Management District data, a health advisory -- a comparatively low-level alert -- was issued somewhere in the agency s region of jurisdiction 169 times in 1979, 152 times in 1980 and 159 times in 1981. The stage 1 threshold was met 120, 101, and 99 times during those three years.
So what did these advisories mean in a practical sense? For a health advisory , the lowest of these levels, all children are supposed to discontinue prolonged, vigorous outdoor exercise lasting longer than one hour, and susceptible persons, such as those with heart or lung disease should avoid outdoor activity, including calisthenics, travel agents india basketball, running, soccer, football, tennis, swimming laps, and water polo.
For the more severe stage 1 episodes, all children are supposed to discontinue all vigorous outdoor activities regardless of duration, including physical education classes, sports travel agents india practices, and athletic competitions.
This suggests that Obama s claim is slightly exaggerated. He said that there were days where folks couldn t go outside, but nothing in the rules addressed what healthy adults could do, including travel agents india healthy college-age kids. Rather, the rules addressed adults with compromised health as well as children.
The White House pointed us to a Newsweek article from Sept. 24, 1979, when Obama was just settling in at Occidental, that documents what it called the worst L.A. smog in 24 years. Tennis courts stood empty, the article said. Golf courses lay nearly deserted. Schools canceled recess, and the usual parade of joggers around Pasadena s Rose Bowl dwindled travel agents india to just a handful.
We found other first-hand testimony. Char Miller, a professor of environmental analysis at Pomona College in the Los Angeles suburb travel agents india of Claremont, recalls enduring smog alerts travel agents india when he was a student at neighboring Pitzer College in the mid 1970s. travel agents india There were way too many days when you could not see the mountain that today frames my office window, travel agents india he said. It was possible travel agents india to not know it was there for months at a time.
When I got there in 1973, I played a vigorous game of basketball in an un-air-conditioned gym, Kelly said. I don t remember the end of the game, just waking up in the early evening with a pounding headache and watering eyes and wheezing in my dorm room. Turns out there was a stage 2 smog alert going on that afternoon, and I didn t have a clue.
The idea that folks couldn t go outside travel agents india is an oversimplification. The advisories -- and they were only advisories -- were aimed at children and people who had existing health concerns. But Obama is right that smog was a severe problem at the time in the Los Angeles region. On balance, we rate his claim Mostly True.
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