9.1: Air Quality as the Genesis for Climate Policy

Urban smog in the Los Angeles basin is legendary. On many days, downtown skyscrapers and even the Hollywood sign blur into a dirty haze (Figure 9.1.1). Geography plays an important role; the San Gabriel Mountains create what is known as an inversion layer of warm air that traps the smog-laden cooler air below and prevents air pollution from dispersing. However, the region’s air quality problems are rooted in the sheer number of cars and industrial pollution sources.

Figure 9.1.1 Smog in downtown Los Angeles, circa 1995. California’s experience since the 1940s in combating air pollution laid the groundwork for climate policy. Reproduced with permission from the Dorothy Peyton Gray Transportation Library and Archive at the Los Angeles County Metropolitan Transportation Authority.

Southern California smog paradoxically laid the foundation for California’s ambitious climate policy agenda and helped the state become one of the most energy efficient and least polluting in the country. The severity of air pollution forced a response that led to the creation of the institutional and legal framework that would later be harnessed in the fight against climate change.

A Dutch-American chemist, Arie Haagen-Smit, was the first to demonstrate, in the 1940s and 1950s, that Southern California smog was being caused by tailpipe emissions and smokestack gases. In 1968, Haagen-Smit became the first chair of the California Air Resources Board (CARB), a state agency that was created to help Californians address the problem of air pollution. Over the years, CARB developed and enforced air quality regulations, often acting earlier or more aggressively (sometimes both) than the federal government and other states. Indeed, California’s tailpipe standards for automobiles, controlling hydrocarbons and carbon monoxide (CO), took effect in 1966—2 years before the first federal standards.

In the 1970s and earlier, officials in the Los Angeles basin issued many smog alerts when ozone concentrations reached 0.20 parts per million (ppm), warning residents to limit their physical exertion and sometimes even to stay indoors. Air quality staff recorded a maximum 1-hour ozone concentration of 0.58 ppm in 1970, nearly five times higher than the 0.12 ppm health-based standard that would be adopted later that decade. As late as 1975, the South Coast Air Quality Management District issued smog alerts on 118 days. But air quality started getting better in the 1980s and has improved steadily ever since. By 1990, there were only 42 alerts, and there were none by 2000. These marked improvements came despite enormous population growth in the greater Los Angeles area, from around 10 million people in 1970 to around 17 million people in 2015.

One regulatory approach used by CARB and its federal counterparts in the 1970s and 1980s is known as command and control—the government commands firms and individuals to behave in a certain way, or to adopt a certain technology, and controls or monitors compliance. For example, bans on lead in gasoline, first implemented by CARB in 1992, 3 years in advance of the federal government, fall into this category. A closely related approach is called performance standards—the government sets a limit on how much pollution can be produced for a given amount of activity but does not specify the precise technologies that must be used to achieve the standard. Auto tailpipe standards that dictate acceptable pollution releases in grams per mile are a good example of the performance standard approach that California has used.

Over the same period, California’s environmental policy began to address broader questions of energy, normally using the same framework of command and control and performance standards. Through uniform building codes, appliance standards, and power plant requirements, the state steadily cranked down its per capita energy consumption and associated air emissions. While it’s exceedingly difficult to show precisely how any particular environmental or energy policy affected pollution or consumption levels, many of California’s trends (discussed in Section 9.4) are very encouraging.