Evolution of the climate in the next million years: A reduced-complexity model for glacial cycles and impact of anthropogenic CO2 emissions

Abstract

This research introduces a simplified model for simulating long-term climate evolution driven by orbital forcing and anthropogenic CO2 emissions. This model, consisting of three coupled differential equations, accurately reproduces glacial-interglacial cycles of the past 800,000 years, demonstrating strong agreement with paleoclimate data. The model predicts long interglacial periods between now and 120,000 years, followed by a glacial inception around 50,000 years in the future under natural conditions. However, anthropogenic CO2 emissions already emitted have the potential to postpone the next glacial period by at least 120,000 years, and significantly higher emissions could lead to a prolonged ice-free state lasting hundreds of thousands of years, significantly altering the Earth’s future climate trajectory.