Those estimates are roughly in line with other studies in the scientific literature that show costs go up faster the later climate initiatives begin. Every year of delay means more fossil fuel facilities will need to be retired early, and more clean energy deployed annually, to meet the same target, says Zeke Hausfather, director of climate and energy at technological research group Breakthrough Institute.

For example, the Energy Innovation report finds that delaying climate policies until 2030 means building nine times more renewable energy capacity per year by the mid-2030s. This is likely to lead to a “global economic shock,” the report’s authors state.

The problem is physics. The world keeps emitting carbon dioxide. Just as a bathtub fills up with water, our atmosphere is filling up with added CO2 from human activities. A business-as-usual scenario means CO2 levels will exceed four-times pre-industrial levels by 2100—far above what is compatible with a stable climate. Slowing and stopping warming means eliminating emissions and removing CO2 from the atmosphere. Even in a best-case scenario, temperatures and sea level will continue to rise for centuries after an emissions peak.

Policymakers may finally be getting the message. Last year, the European Union announced plans to eliminate net emissions by 2050, and several member states have passed this target into law. In the US, the Biden administration’s new climate plan will zero out greenhouse gas emissions from the power sector by 2035, on the way to net-zero emissions nationwide no later than 2050. Policymakers’ intent is also driving corporations, responsible for most of the world’s emissions, to move ahead of the coming regulations. At least 1,100 companies have voluntarily adopted emission targets, according to the Science Based Targets initiative, about a third of which plan to meet the 1.5°C target set by the Paris Agreement.

“I’m very optimistic by the policy goals being discussed today,” says Megan Mahajan, a co-author of the report and senior policy analyst at Energy Innovation. “They are the goals needed to get us on the path to net-zero emissions.”

📬 Sign up for the Daily Brief

Our free, fast, and fun briefing on the global economy, delivered every weekday morning.