[A-CG35] 地球規模環境変化の予測と検出

[ACG35-09] Predictability of air-sea CO₂ fluxes with an Earth system model incorporating an initialization system

*渡辺 路生¹、建部 洋晶¹、小山 博司¹、片岡 崇人¹、羽島 知洋¹、渡部 雅浩²、河宮 未知生¹ (1.海洋研究開発機構、2.東京大学)

キーワード：地球システムモデル、炭素循環、10年規模予測

Increased atmospheric CO₂ concentration causing global warming, which means the need for accurate prediction of variations in atmospheric CO₂ concentration is increasing. Uptake of CO₂ at the ocean and land surfaces is one of the fundamental processes in the global carbon cycle, and it is known to fluctuate in response to inherent climate variabilities such as the Interdecadal Pacific Oscillation (IPO) and the Atlantic multidecadal Variability (AMV). Therefore, predicting the changes in the carbon cycle associated with inherent climate change is essential for decadal-scale prediction of the carbon cycle. We are currently working on the decadal-scale prediction of the carbon cycle by incorporating an initialization system into an Earth system model that can represent the global carbon cycle. By comparing the results of the hindcast experiment with observations, it was found that the change in the CO₂ uptake by the ocean is predictable for about five years. Since the variations of air-sea CO₂ flux depends mainly on the variations of dissolved inorganic carbon concentration in the ocean, it is important to improve the prediction performance of the variations of dissolved inorganic carbon concentration in the ocean.