The world will zoom well past its target for global temperature rise in the next few years, a United Nations report warned Wednesday, exposing people and ecosystems to profound climate impacts that nations had pledged to avoid.

In a first-of-its-kind report, nearly 50 leading climate scientists say humanity's best remaining option for limiting this overshoot is to zero out greenhouse gas emissions and use carbon removal strategies to bring average temperatures back down to a tolerable level.

Eleven years after nations at the Paris climate talks pledged to limit warming to 1.5 degrees Celsius (2.7 degrees Fahrenheit) above preindustrial levels, the new report is the first U.N. document to explicitly state that exceeding 1.5 is inevitable and to lay out a strategy for reversing excess temperature rise.

"Let's be clear that the 1.5 target is still the goal," said Inger Andersen, executive director of the U.N. Environment Program (UNEP), which published the report, titled "Limiting Overshoot." "But now we need to approach it differently — from above."

To have a chance of bringing temperatures back down before the year 2100, the report says, the world should pursue a pathway of "overshoot, peak and decline."

It starts with cutting planet-warming pollution 55 percent by 2035 and nearly eliminating emissions by mid-century. This will allow global temperatures to peak around 1.8 degrees Celsius (3.2 degrees Fahrenheit) above 19th-century levels.

The dangers at that scale of warming will still be significant. Rising sea levels will engulf small island nations and submerge many coastal communities. Heat waves, hurricanes, wildfires and floods, which already cause hundreds of thousands of deaths each year, will become many times more extreme. Without aggressive adaptation measures, global food production could decline by 14 percent.

As humanity races to adapt to these challenges, the report's scientists say, the world must also aggressively pursue measures that pull heat-trapping gases out of the atmosphere, so global temperatures will start to decline. Options for carbon dioxide removal include natural approaches, like planting forests, as well as technological strategies, such as machines that suck carbon from the air and store it underground.

In a best-case scenario, this pathway will limit the planet's time above 1.5 degrees to a few decades.

Yet even if global temperatures eventually decline to safer levels, the report warns, it will not restore the world we once knew. At least a quarter of the planet's glaciers — critical water sources for mountain communities — will permanently melt away. Species that go extinct cannot be resurrected. Some ecosystems damaged by extreme weather will never recover.

Surpassing the 1.5 target, even temporarily, also increases the risk of triggering tipping points in the climate system, such as the collapse of the Amazon rainforest and the abrupt disintegration of polar ice sheets. Like a person tilting back in a chair until it falls over, these phenomena are irreversible once they're set in motion, and they can scramble crucial weather patterns on a global scale.

Yet even as world leaders increasingly described 1.5 as the only acceptable target, emissions have surged upward, hitting a record high in 2025. Global temperatures last year were about 1.3 to 1.4 degrees Celsius (2.3 to 2.5 degrees Fahrenheit) above the preindustrial average, and some scientists argue that warming is accelerating.

The deadly climate disasters of recent months show that societies are already struggling to cope with this level of warming, said Kristie Ebi, a lead author of the overshoot report and a professor at the Center for Health and the Global Environment at the University of Washington.

Europe's early-warning systems were unable to prevent tens of thousands of excess deaths from successive, record-breaking heat waves. A glacier collapse that occurred with no warning probably caused hundreds, if not thousands, of people in Nepal and Tibet to drown in epic floods. (Source: The Washington Post)

Story Date: September 3, 2026