The President’s Inbox Recap: Climate Change Realism on Earth Day 2025

On the latest episode of The President’s Inbox, Jim sat down with Varun Sivaram, senior fellow for energy and climate and Director of the Climate Realism Initiative at the Council, to discuss where things stand in the fight to limit climate change.

Here are three highlights from their conversation:

1) The world is on course to blow past its target for limiting climate change. Nearly a decade after the 2015 Paris Agreement set the goal of capping the rise in average global temperature to 1.5 degrees Celsius—and absolutely no more than 2 degrees—the planet is headed for a 3-degree increase by the end of the century. That might not seem like a big figure, but it represents a profound and dangerous departure from the historical environment. Climate systems do not respond linearly. Instead, each degree of warming multiplies the risk of crop failures, water shortages, wildfire outbreaks, and extreme weather events. “This is no trifling matter,” Varun argued, “and it could mean fundamental changes to society as we know it.” Thus far, the United States has refrained from prioritizing environmental issues in its foreign policy, while international initiatives to finance carbon reduction in developing countries have been both insufficient and ineffective. Global cooperation has helped increase awareness and set targets to reduce emissions, but these will not prevent severe climate change.

2) The United States can neither stop climate change on its own nor escape its consequences. A leading contributor of greenhouse gas emissions in the twentieth century, the United States has cut its emissions by about 15 percent since their 2007 peak. For the remainder of the twenty-first century, however, nearly 87 percent of global emissions are projected to originate outside the United States and other advanced economies. Further U.S. emissions reductions, therefore, will have at best a marginal global impact. This does not mean that the United States can insulate itself from the consequences of global warming. Unpredictable environmental catastrophes respect neither human-made borders nor who is responsible for their causes. Rising sea levels, disrupted supply chains, and refugee migrations will threaten the United States’ economy, security, and social cohesion. “We’re headed into a lightning storm,” Varun cautioned. “Assuming that everything will be manageable would be very imprudent.”

3) Controversial measures may become necessary to avoid a climate catastrophe. The United States is likely to turn to steps such as deploying artificial intelligence for clean energy management, preventing people from living in at-risk areas by denying insurance coverage, and using labor-disruptive industrial policy to scale clean technologies. At the same time, emerging innovations like solar cells and solid-state batteries can help reduce the use of fossils fuels. But these changes may not come fast enough or make a big enough dent in halting extreme climate change. That could lead countries to consider moonshot ideas such as geoengineering. Solar radiation management, which involves reflecting sunlight back into space, could theoretically lower global temperatures. However, the technology carries serious risks: uneven weather impacts, regional winners and losers, and new geopolitical tensions over who controls the climate. “The moral hazard,” Varun explains, “is that with the prospect of using [geoengineering], the world won’t reduce its fossil fuels.” This is all assuming that geoengineering even works and doesn’t precipitate a climate catastrophe of its own. Regardless, the new era of climate realism must acknowledge the scale of the crisis, accept that we cannot fully prevent it, and prepare for the hard choices that may now lie ahead.

If you’re looking to read more from Varun, check out his latest piece for CFR.org, titled “We Need a Fresh Approach to Climate Policy. It’s Time for Climate Realism.”