Upload
rane
View
214
Download
0
Tags:
Embed Size (px)
DESCRIPTION
A&O2
Citation preview
In this sec*on we are going to learn about a type of pollu*on that is familiar to many of us: Los Angeles smog. This is also o<en called photochemical smog. It is well known that this smog has nega*ve health effects and that, when it is at its worse, people can directly feel the effect through tearing eyes and difficulty breathing. However, the probably most obvious effect of smog is the forma*on of par*cles that degrade the visibility in many ci*es. Here you can see such an example for Los Angeles. Many of you have probably see this type of haze during sunny days in Los Angeles or when you fly into the LA-‐Basin. It should be noted that, while o<en called Los Angeles smog, this phenomenon can be found in may urban areas. You may have seen recent headlines of air pollu*on in China, which shows the prevalence of photochemical smog in ci*es.
1
Here is one ar*cle published in 2013 in the New York Times, describing the impact of smog on human health. If you pay aQen*on you will see that ar*cles on air pollu*on appear regularly in the press, showing that this topic remains one of our most severe environmental problems.
2
In this sec*on we will discuss various aspects of Photochemical smog. We will use Los Angeles as our example because it is were this type of smog was first recognized and because LA is on the forefront in comba*ng this type of air pollu*on. Also, for many of us this type of smog is part of our daily life and we can o<en see its effects. We will begin this sec*on with a short movie that presents the history of smog in Los Angeles. We will then present the main chemical components of LA smog and compare them to those from London type smog. As some of the main pollutants are chemically formed in the atmosphere, we will then learn about the chemistry of smog, and in par*cular the forma*on of ozone. We will then show how par*cles, another component of smog, decrease visibility in urban areas. Finally we will discuss the various environmental policies and measures that have led to an improvement in air quality in Los Angeles and how the future of LA smog will look like.
3
Some of you may have heard about air pollu*on in the 1960 and 1970’s in Los Angeles, but it is hard to comprehend how severe air pollu*on was then in Los Angeles. We therefore will start with a sec*on on the history of LA smog, to understand how bad air quality was in the past, what was done to improve air quality, and to put today’s air quality in perspec*ve In the following we will show a movie that presents the history of Los Angeles pollu*on. This movie was made by the California Air Resources board, the state agency that is in charge of air quality in the state of California. Pleas pay aQen*on to the movie as we will ask you to provide a short summary about the severity of past air pollu*on and how it compares to today at the end.
4
5