Newly unearthed documents contain warning from head of Air Pollution Foundation, founded in 1953 by oil interests

Major oil companies, including Shell and precursors to energy giants Chevron, ExxonMobil and BP, were alerted about the planet-warming effects of fossil fuels as early as 1954, newly unearthed documents show.

The warning, from the head of an industry-created group known as the Air Pollution Foundation, was revealed by Climate Investigations Center and published Tuesday by the climate website DeSmog. It represents what may be the earliest instance of big oil being informed of the potentially dire consequences of its products.

“Every time there’s a push for climate action, [we see] fossil fuel companies downplay and deny the harms of burning fossil fuels,” said Rebecca John, a researcher at the Climate Investigations Center who uncovered the historic memos. “Now we have evidence they were doing this way back in the 50s during these really early attempts to crack down on sources of pollution.”