The report, written by members of Shell’s Greenhouse Effect Working Group, said that scientists believed that the effects would become detectable late in the 20th or early 21st century.
It was based on a 1986 study, although the document reveals that Shell had commissioned “greenhouse effect” reports as early as 1981.
The documents were found by Jelmer Mommers, a reporter with De Correspondent. They were posted on the Climate Files website, which is sponsored by the Climate Investigations Center, an environmental activist group.
Shell’s working group knew three decades ago that climate change was real and formidable, warning that it would affect living standards and food supplies and have social, economic and political consequences.
The working group also warned that rising sea levels could impair offshore installations, coastal facilities, harbors, refineries and depots.
The documents contrast with Shell’s public stance on climate change during the 1990s, when the company was a member of the Global Climate Coalition. The industry group raised doubts about the science of climate change and opposed the Kyoto Protocol, the global agreement reached in 1997 to fight climate change.
Shell withdrew from the industry group in 1998, with then-President Mark Moody-Stuart saying: “We recently met them, and it was concluded our differences of opinion were irreconcilable. We will not renew our subscription,” according to a contemporary press report.
The 1988 report estimated that in 1981, 44 percent of carbon-dioxide emissions came from oil, 38 percent from coal and 17 percent from natural gas.
“With fossil fuel combustion being a major source of CO2 in the atmosphere, a forward looking approach by the energy industry is clearly desirable, seeking to play its part with governments and others in the development of appropriate measures to tackle the problem,” the report said.
At the same time, however, the report said that “the likely time scale of possible change does not necessitate immediate remedial action.”
On Thursday, Shell issued a statement in response to the publication of the report.
“The Shell Group’s position on climate change has been a matter of public record for decades. We strongly support the Paris Agreement [on climate change] and the need for society to transition to a lower carbon future, while also extending the economic and social benefits of energy to everyone,” the company said. “Successfully navigating this dual challenge requires sound government policy and cultural change to drive low-carbon choices for businesses and consumers. It requires cooperation between all segments of society.”