Model Comparison › Climate Pathway Calibration

Physical Climate Pathway Calibration (1.5°–4°C)

CMIP6 multi-model mean temperature trajectories for SSP1-1.9, SSP2-4.5, SSP3-7.0, and SSP5-8.5 with p10/p90 likely ranges. IPCC AR6 carbon budget accounting, warming probability distributions, and remaining-budget exhaustion timelines.

SCENARIOS: SSP1-1.9 SSP2-4.5 SSP3-7.0 SSP5-8.5

Show p10–p90 bands

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SSP1-1.9 warming 2100

p10–p90 range °C

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SSP2-4.5 warming 2100

p10–p90 range °C

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SSP3-7.0 warming 2100

p10–p90 range °C

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SSP5-8.5 warming 2100

p10–p90 range °C

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1.5°C budget (67%) left

GtCO2 at current pace

CMIP6 Temperature Trajectories 2025–2100 (°C above 1850–1900 baseline)

Carbon Budget Status

Warming Probability at Selected Year

Scenario	P(>1.5°C)	P(>2°C)	P(>3°C)	P(>4°C)

Budget Exhaustion Timeline — Years Remaining

Sources: IPCC AR6 WG1 Chapter 4 (CMIP6 multi-model mean temperature trajectories, Table SPM.1 / Figure SPM.8) · IPCC AR6 WG3 Table SPM.2 (remaining carbon budgets, adjusted to 2025 reference) · Hausfather et al. (2022) "Evaluating the performance of past climate model projections" Geophysical Research Letters · Tokarska et al. (2020) "Past warming trend constrains future warming in CMIP6 models" Science Advances. TCRE (Transient Climate Response to Cumulative Emissions) = 0.45°C/1000 GtCO2 (IPCC AR6 central estimate).