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Thermal Lag

Even if all emissions stopped today, the planet would keep warming for decades because CO₂ persists and oceans release stored heat slowly. This is thermal lag — and it is why surface cooling matters now.

Scientific detail

Thermal lag arises from the multi-decade to multi-century atmospheric lifetime of CO₂ and the large thermal inertia of the ocean, which delays surface temperature equilibration to a given radiative forcing. Committed warming from historical emissions is estimated at several tenths of a degree beyond present. Surface-based cooling can offset part of this committed warming while decarbonization takes effect.

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