26.01.2026

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Overshooting temperature targets

Overshooting 1.5°C is inevitable!

Irreversibilities under temperature overshoots

1. Reversible:
• Surface air temperature
• Precipitation
• on a global scale (not on a local scale)

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3. Irreversible:
• Sea level rise, glacier melt, permafrost carbon loss
• Biodiversity (waves of extinctions)
• Tipping elements

Overshooting 1.5°C is inevitable. Minimizing the magnitude and duration of overshoot is essential

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Ritchie, et al., GTPR 2025

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Impacts of overshooting 1.5°C on tipping risks

Number of tipped elements

Ritchie, et al., GTPR 2025

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Impacts of overshooting 1.5°C on tipping risks

Ritchie, et al., GTPR 2025

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Overshooting climate targets increases tipping risks

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Result:

Overshooting 2.0°C means entering a very high risk zone for tipping elements!

Overshooting climate targets increases tipping risks

Consequences of overshooting 1.5°C for the Amazon rainforest

Amazon deforestation

Amazon rainforest

2.8°C warming

1.9°C warming

Wunderling et al., in review

Based on Wunderling et al., 2022, PNAS

A safe overshoot for the Amazon rainforest?

A safe overshoot for the Amazon rainforest?

Thanks – Next Up:

• Governance of Tipping Points (Simon Willcock)
• Coral Reefs (Melanie McField)
• Positive Tipping Points (Tom Powell)

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Nico Wunderling nico.wunderling@pik-potsdam.de, wunderling@c3s.uni-frankfurt.de

Implications of Overshooting 1.5°C for Earth System Tipping Points

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Overshooting tipping points

Ritchie et al., 2021, Nature

AMOC model: 1D Stommel-Cessi model

Definition:

An overshoot is a temporal transgression of a a temperature target (sometimes a temporal transgression of a tipping point)

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Overshooting climate targets increases tipping risks

Wunderling et al. (Nature Climate Change, 2023)

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Overshooting climate targets increases tipping risks

Wunderling et al. (Nature Climate Change, 2023)