“The chance of holding global warming to below 1.5°C above pre-industrial levels with no or limited overshoot is gone.” That’s the first line from United Nations Environment Programme (UNEP) Executive Director Inger Andersen in the foreword to UNEP’s Emissions Gap Report 2026: The Point of Return, released Oct. 21.
Now, the report says, the question is how to get onto a pathway with the “lowest possible” remaining overshoot. This route aims to limit peak warming to 1.7-1.8°C by mid-century, preserving a 50 percent possibility of reduction to 1.5°C by 2100. This would require cutting emissions by 18 percent by 2030, 45 percent by 2035, and 69 percent by 2040 (all against 2025 levels). Countries’ current pledges, by comparison, would cut emissions by just 5-8 percent by 2030 and 11-15 percent by 2035; these are predicted to lead to about 2.6°C of warming – and that assumes they fully deliver on those reductions. Getting onto the “lowest possible” overshoot pathway, therefore, requires significant further interventions.
The externally reviewed report was produced by a team of 40 international authors, led by UNEP-Copenhagen Climate Centre Chief Scientific Editor Anne Olhoff, and including leading scientists from major climate-modeling and policy research centers.
Where might policymakers, academics, journalists, and others go from here? Below is a non-exhaustive list of questions to consider in light of this week’s findings.
1. What are the legal implications of overshooting 1.5°C?
In the International Court of Justice (ICJ)’s 2025 Advisory Opinion, the Court held, among other things, that the 1.5°C benchmark had become the States’ primary goal under the Paris Agreement, which calls for aiming for “well below 2°C” while pursuing efforts toward 1.5°C. Regional and domestic courts have also been referencing this benchmark in legal frameworks for State obligations with respect to climate change.
Now, UNEP concludes that the 1.5°C target cannot be met without overshoot. What, then, is the target’s legal effect? Does the obligation to pursue 1.5°C convert to an obligation to minimize the overshoot, or to something else? Does each additional year or one-tenth of a degree (the meaningful unit of measurement identified in the report) give rise to an additional claim of non-compliance? These and other questions related to overshoot are already being interrogated by the international legal community (including by our friends at the American Branch of the International Law Association’s International Law Weekend today), and the latest UNEP report only makes the questions more urgent.
2. How will courts use the report’s new emissions benchmarks?
A number of “fair-share” or “rights-based” climate change cases, largely in European national or regional courts, have measured State and corporate obligations against what would be necessary to achieve 1.5°C. Two Dutch cases, for example, benchmarked to 43-45 percent cuts by 2030. UNEP now calls for steeper cuts tied to a later baseline, but also calls part of the gap “unbridgeable” – so depending on how this is read, it could help or hurt plaintiffs in such cases. It also raises the question of how courts will treat judgments built on old figures, e.g. if appealed or if plaintiffs seek enforcement. And how might this intersection of litigation and shifting science impact domestic political will to entertain climate cases at all – particularly amid some signs of a backlash against climate change litigation, like New Zealand’s August 2026 law barring tort claims for climate change damages?
3. Who pays (or should pay) for the overshoot years?
UNEP’s report describes a process for bringing temperatures back down by 2100, implying a cost that will largely fall on future generations. This adds an additional dimension to long-running debates about obligations and remedies for climate change, which already involve stakeholders including major historical emitters, the least-developed countries that bear the worst impacts of climate change despite being only incidental contributors, and private companies.
4. How could 320 gigatons of carbon removal be governed?
The “lowest possible” overshoot pathway depends on 320 gigatons of carbon removal this century; the report notes that the global ability to do so “is uncertain, because of socioeconomic and technological challenges to the scale-up of CO2 removal measures and technologies.” Even assuming the scientific dimension is solved, this also raises a host of complex governance questions, including:
- Who is responsible for verifying removal and ensuring that what’s removed stays put?
- How would removal regimes compete with existing land use rights? What happens when such projects compete with food production, housing, or Indigenous rights? How do ocean-based removal projects intersect with international governance there?
- How do steps toward the 320 gigatons of removal intersect with existing obligations, e.g. could such removal be counted toward a State’s national contribution, and how would they be prevented from replacing emissions cuts?
5. What are the consequences of U.S. exit from the UNFCCC?
The U.S. withdrawal from the U.N. Framework Convention on Climate Change (UNFCCC) formally takes effect on Feb. 27, 2027, and the report notes that the withdrawal (along with revised estimates of historical emissions) has already worsened projected warming. It also warns that an apparent narrowing of the distance between State pledges and policies actually reflects removal of the U.S. pledge rather than real progress.
The United States stands out in the report, including in a subsection entitled “Emissions growth slowed down in the G20, with the United States of America being the major exception” and in a footnote noting the U.S. disagreement with the report, included at the request of the U.S. State Department. The choices of the United States – the world’s second-largest current emitter and largest historical emitter – will necessarily shape the global path. A related question, then, is what other paths might be available to reduce U.S. emissions, such as state and local activity or civil-society or private-sector leadership.
6. How are the Strait of Hormuz crisis and broader geopolitical instability shaping the energy transition?
The report notes that the Strait of Hormuz closure materially affected energy trends, driving up the price of oil and causing States to seek alternative energy sources. The net impact on emissions is unclear, as some States turned to coal and fuel subsidies while others have cut demand or are accelerating development of renewables. More broadly, conflicts emit directly and drive trends that, as the Strait of Hormuz shows, can both increase and decrease emissions depending on the second-order behavior that follows. The report also notes that energy security is increasingly a driver of clean-energy development in its own right.
7. How does each tenth of a degree of warming translate to our lives?
“In August 2026,” the report says, “global temperatures tied the record for the hottest month ever observed.” Extreme weather shapes health, labor protections, housing and insurance, migration, and nearly every dimension of public life.
The report takes each one-tenth of a degree, and each year above 1.5°C, as meaningful units of change. And with good reason: each also means real impacts on humans living in a climate-inflected world.
