It can be argued that the current presidential administration appears to lack interest in the traditional mission of the Environmental Protection Agency.

As a candidate, Donald Trump advocated wholesale repeal of environmental regulations and increased production of fossil fuels. He has also called climate science a "hoax" created by China to hurt the U.S.

As president, Trump picked Scott Pruitt to lead the EPA. Pruitt is a climate-science denier who sued the agency he now leads multiple times over its enforcement of environmental regulations.

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But if anyone should doubt the importance of the EPA, it's instructive look back a few decades.

That's what Popular Science did, as part of an ongoing series on the agency the publication started following Pruitt's confirmation last month by the U.S. Senate.

It compiled a series of photos from the U.S. National Archives showing what the country looked like before EPA rules limited emissions and began to clean it up.

International Paper Company mill, 1973 [From EPA Documerica series]

International Paper Company mill, 1973 [From EPA Documerica series]

The EPA was created in 1970, through an executive order signed by President Richard Nixon.

Between 1971 and 1977, the agency recruited freelance photographers to document the state of the environment, as efforts to address rampant pollution got underway.

The result was a trove of more than 15,000 photos in the series "Documerica," which were digitized by the National Archives in 2011.

MORE: A Brief History Of Smog, Which Led To Electric Cars: Recommended Reading (Dec 2011)

Those images show a country very different from the one we enjoy today.

Clouds of smoke billow from industrial smokestacks, and smog in major cities obscures even large landmarks, including New York City's George Washington Bridge.

EPA environmental regulations made possible many things we take for granted today—like being able to see the horizon.

Smog over Louisville, 1972 [From EPA Documerica series]

Smog over Louisville, 1972 [From EPA Documerica series]

For vehicles, the EPA instituted limits on three pollutants—carbon monoxide, unburnt hydrocarbons, and nitrogen oxides—collectively known as "criteria emissions" that contributed to smog formation.

In addition to reducing air pollution and damping the effects of climate change, regulations on emissions and fuel economy were harmonized for vehicles starting with the 2012 model year.

Since 1975, fuel-economy rules from the NHTSA have increased the efficiency of modern cars, helping to save owners money on fuel as an added benefit.

The two sets of regulations had to come into alignment when the EPA, backed by a U.S. Supreme Court decision, took on the additional responsibility of limiting emissions of carbon dioxide, a greenhouse gas.

The EPA recently locked in rules that cut exhaust emissions of carbon dioxide for vehicles in model years 2022 through 2025, but automaker lobbyists would like to see that decision reversed.

They have appealed to both President Trump and EPA administrator Pruitt to reopen the midterm review process for emissions rules.

1970s Los Angeles smog depicted in the Honda short film

1970s Los Angeles smog depicted in the Honda short film

The EPA had been given until April 2018 to determine the feasibility of automakers meeting emissions rules, but the agency completed the process in January, before the Trump administration took office.

Automakers hope that revisiting that review process may lead to less-stringent standards for the final period of current regulations.

The challenge with carbon dioxide, of course, is that its vastly increased concentrations in our atmosphere is not visible in the same way as the criteria pollutants documented 45 years ago.

The effects of climate change are seen in changing weather patterns, rising average temperatures, and potentially higher ocean levels as ice caps melt.

Many of those impacts are less easily documented than the uncontrolled emission of "criteria pollutants" the EPA so ably limited in the decades after its formation.

Green Car Reports respectfully reminds its readers that the scientific validity of climate change is not a topic for debate in our comments. We ask that any comments by climate-change denialists be flagged for moderation. Thank you in advance for helping us keep our comments on topic, civil, respectful, family-friendly, and fact-based.


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