Overshoot reshapes climate strategies—but the path to net zero remains unchanged - Earth - Environment

Distributional economic impacts of temporary overshoot in time and space. Credit: Nature Climate Change (2026). DOI: 10.1038/s41558-026-02563-7

Temporary overshoot of global temperature targets—particularly the 1.5°C goal of the Paris Agreement—is no longer just a modeling concept. New research, published in Nature Climate Change and led by the Euro-Mediterranean Center for Climate Change (CMCC) in collaboration with 14 research institutions from 10 countries, traces how overshoot has evolved over the past three decades, from a scenario tool used to explore ambitious targets to a structural feature of climate scenarios, reflecting the tension between more ambitious temperature targets and continued emissions growth. What began as a modeling tool to explore climate goals has become an almost inevitable outcome in pathways compatible with the Paris Agreement.

The research shows that limited overshoot—for example, temporary warming to around 1.8°C—does not change the fundamental timeline to global net zero CO₂ emissions, still expected between 2050 and 2060. "In a world of limited overshoot, the core objective of strong decarbonization and net zero remains intact," says CMCC's scientist Massimo Tavoni. "What overshoot does, however, is to reshape how the transition unfolds, how we implement the transition, manage risks, and ensure policies are fair and effective."

Although the timeline for reaching net-zero emissions remains unchanged, overshoot changes how climate impacts and mitigation efforts are felt over time. Even small overshoots make extreme events more likely, with greater social and economic consequences. They can also shift mitigation burdens across generations, potentially placing more strain on future societies.

The long-term effects depend on how persistent climate damages turn out to be—an area where significant uncertainty remains. "If impacts cause lasting physical or social disruptions, temporary overshoot could leave enduring consequences even after temperatures fall," says Tavoni. "If damages are more reversible and adaptation measures are effective, the long-term impacts may be more limited. Understanding this persistence is crucial to understanding recovery from overshoot."

Overshoot also increases the demand for carbon dioxide removal (CDR) technologies, since excess CO₂ must be actively removed for temperatures to decline. Yet the study emphasizes that CDR is needed even in pathways with limited overshoot, and that its scale ultimately depends more on policy choices than on overshoot itself. Larger overshoots beyond Paris targets, however, create deep uncertainties, potentially requiring extensive mitigation measures whose feasibility and implications are still largely unknown.

The study underscores the importance of interdisciplinary approaches that combine physical climate science, ecological systems, socioeconomic processes, and uncertainty analysis. By integrating these dimensions, future models can better inform climate strategies in a world where temporary overshoot is unavoidable.

"Overshoot is no longer just an abstract scenario," adds Tavoni. "It is a reality that both scientists and policymakers must navigate carefully. Addressing overshoot effectively requires integrating physical, ecological, and socioeconomic dimensions, and carefully accounting for uncertainty in future scenarios. Indeed, we can remain on track to meet the Paris Agreement's goals." 

Provided by Euro-Mediterranean Center on Climate Change

by Euro-Mediterranean Center on Climate Change

edited by Gaby Clark, reviewed by Robert Egan 

Source: Overshoot reshapes climate strategies—but the path to net zero remains unchanged