The scientists and experts trying to communicate the threat of climate change, however, “have been opposed for years,” says Mann, “by the single most-organized, well-funded disinformation campaign in the history of human civilization: The fossil fuel industry’s concerted effort to confuse the public and policymakers about the reality and threat of human-caused climate change.”

“In the absence of the billions of dollars spent by fossil fuel interests and front groups and politicians in their pay to obscure public understanding of climate change risk, I’m convinced we would have acted decades ago.”

Now, the action required to achieve the Paris goals within an ever-shortening timeframe is unprecedented. If the world hopes to limit warming to 1.5 C, the targets agreed to in the Paris climate deal must become five times more ambitious.

“Emissions need to go down by 55% by 2030. There is no way we are going to make it if we don’t step up action as of 2020 with ambitious plans,” UNEP’s executive director, Inger Andersen, told a press conference after the release of the U.N.’s November report. “Our collective failure to act early means we now must deliver deep cuts to emissions, over 7% each year.”

But one month later, environmentalists criticized the COP25 negotiations for allowing major polluters to engage in the conversation; fossil fuel companies have been accused of spending millions in sponsorship and lobbyists to try influence the talks and water-down commitments.

Clean Energy And Activism

As the warnings of catastrophic climate change become increasingly loud, however, there has been some progress over the last ten years. And many of the technological breakthroughs and new social movements have given rise for optimism.

The clean energy revolution shows no signs of stopping. Since 2009, more than $2.5 trillion has been invested globally in renewables, according to Bloomberg New Energy Finance. Solar capacity has risen from about 25 gigawatts at the start of 2010 to an estimated 663 GW today (for comparison, one of the largest coal power plants in the U.S. has a 3.5 GW generating capacity providing enough electricity for 1.9 million homes).

And the International Energy Agency forecasts that, with wind and solar energy in many countries now competitive with, or even cheaper than, fossil fuel electricity, renewables will expand by 50% over the next five years.

“No other technologies have risen to the challenge of climate change with such speed and success,” Susan Rakov, chair of Environment America’s research and policy center clean energy programme, said in a statement. At the same time, coal is slowly on the decline — this April saw the share of power provided by renewables in the U.S. surpass that of coal for the first time ever. And globally, energy from coal is expected to drop by 3% in 2019.