2024-11-26 パシフィック・ノースウェスト国立研究所(PNNL)
<関連情報>
- https://www.pnnl.gov/news-media/delay-and-pay-tipping-point-costs-quadruple-after-waiting
- https://www.nature.com/articles/s41612-024-00768-1
ティッピング・ポイント付近での極海氷の最適制御 Optimal control of polar sea-ice near its tipping points
Parvathi Kooloth,Jian Lu,Craig Bakker,Derek DeSantis & Adam Rupe
npj Climate and Atmospheric Science Published:26 November 2024
DOI:https://doi.org/10.1038/s41612-024-00768-1
Abstract
Several Earth system components are at a high risk of undergoing rapid, irreversible qualitative changes or “tipping” with increasing climate warming. It is therefore necessary to investigate the feasibility of arresting or even reversing the crossing of tipping thresholds. Here, we study feedback control of an idealized energy balance model (EBM) for Earth’s climate, which exhibits a “small icecap” instability responsible for a rapid transition to an ice-free climate under increasing greenhouse gas forcing. We develop an optimal control strategy for the EBM under different forcing scenarios to reverse sea-ice loss while minimizing costs. Control is achievable for this system, but the cost nearly quadruples once the system tips. While thermal inertia may delay tipping, leading to an overshoot of the critical forcing threshold, this leeway comes with a steep rise in requisite control once tipping occurs. Additionally, we find that the optimal control is localized in the polar region.