853 / 2024-09-19 16:28:25

Asymmetric and irreversible response of tropical cyclone potential intensity to CO2 removal

Tropical cyclone,Carbon dioxide removal,Potential intensity

Understanding the behaviors of tropical cyclone (TC) intensity under the CO₂ removal scenario is important for future climate adaptation and policy making. Based on the idealized CO₂ ramp-up (from 284.7 to 1,138.8 ppm) and symmetric ramp-down experiments, our results suggest an asymmetric and irreversible response of TC potential intensity to CO₂ reduction. Potential intensity shows an additional enhancement at the same CO₂ level during the CO₂ ramp-down relative to the ramp-up periods (though with regional differences), and does not completely return to the initial value even when CO₂ recovers on multi-decadal to centennial timescale. The enhanced potential intensity is dominated by the increased thermodynamic disequilibrium, which is mainly attributed to the weakened surface winds arising from the El Niño-like warming pattern and inter-hemispheric ocean temperature contrast. Our results highlight the potential risks of stronger storms on the socioeconomic development under the negative carbon emissions pathways.