A new report exposes the many ways that Big Oil has been working to deceive the public on climate change over the past several decades. The media has fallen for many of its tactics, effectively allowing the industry to change the debate on climate science and hide the industry backing behind its front groups and campaigns.

For nearly three decades, top executives at ExxonMobil have known that fossil fuel emissions harm the climate, according to a document uncovered by the Union of Concerned Scientists (UCS). And since then, the UCS report shows, Exxon and other major oil companies have been working to “deceive the public” about the truth on climate change.

The UCS report -- titled “The Climate Deception Dossiers: Internal Fossil Fuel Industry Memos Reveal Decades of Corporate Disinformation” -- is based on a trove of internal company and trade association documents and identifies seven tactics that oil companies have used to sow misinformation and sway public opinion in its favor. Several of these tactics involve spreading “disinformation,” and the media has taken the bait. Here's how:

Including False Balance In Climate Change Coverage

A key document uncovered by UCS is a 1998 memo from the American Petroleum Institute (API) that includes a draft “Global Climate Science Communications Plan.” The plan's stated goal is that a “majority of the American public, including industry leadership, recognizes that significant uncertainties exist in climate science, and therefore raises questions among those (e.g. Congress) who chart the future U.S. course on global climate change.” API's plan says one of its hoped-for “victories” is for media coverage to “reflect balance on climate science.” And indeed, false balance is rampant in mainstream media coverage of climate science. For example, in 2014, every broadcast Sunday news show except CBS' Face the Nation aired segments that included false balance on climate science.

Validating Contrarian Viewpoints

Another API “victory” was for media to recognize “the validity of viewpoints that challenge the current 'conventional wisdom'” on climate change. A 2013 study published in Public Understanding of Science found that conservative media frequently portray contrarians and deniers as objective experts on science. Mainstream media outlets often follow suit, such as when several major newspapers earlier this year described the fossil fuel-funded Heartland Institute as merely one of many climate “skeptics,” which lent validity to the organization's criticism of Pope Francis' climate change encyclical.

Overly Emphasizing “Uncertainty” In Climate Science

UCS also discovered that API vowed to make the media “understand... uncertainties in climate science.” Conservative media often push the false myth that climate science is “unsettled,” and a heavy focus on “uncertainties” in climate science is an unfortunate trend in media stories: a 2013 study from Oxford University showed that nearly 80 percent of climate change stories surveyed were framed in the context of uncertainty. Meanwhile, the science behind human-caused climate change is in fact settled, with the same level of certainty as the science behind cigarettes' causing deadly disease.

Failing To Disclose Industry Funding Behind “Grassroots” Organizations

UCS' report also shows how the oil industry has created fake grassroots organizations to lobby on behalf of the fuel companies. Several Media Matters reports have detailed the media's failure to disclose the funding behind many pro-industry organizations and campaigns -- most notably, Americans for Prosperity, the "grassroots" front group created by the oil billionaire Koch brothers.

Allowing ALEC To Shill For Industry Unnoticed

Finally, UCS reveals the extensive role played by the American Legislative Exchange Council (ALEC), which connects industry executives to state legislators and pushes legislation that furthers the oil industry's agenda. Again, many media outlets have failed to disclose the industry interests behind several ALEC campaigns, particularly its attempts to dismantle clean energy policies.

“Doubt is our product,” a tobacco executive once said, kicking off a decades-long campaign to hide the deadly impacts of smoking from consumers. The fossil fuel industry's campaign to sow uncertainty and introduce doubt into climate change coverage shows how the industry is taking yet another page from Big Tobacco's playbook.