In 2015, the Indian Ocean exhibits an exceptionally weakened CO2 uptake, highlighting strong interannual variability of ocean carbon sink. By utilizing multiple ocean CO2 partial pressure (pCO2) data and a state‐of‐the‐art ocean biogeochemical model, we show that the 2015 ocean CO2 anomaly is characterized by a basin‐wide amplification of ocean pCO2, differing from ocean pCO2 responses to other Indian Ocean Dipole events (e.g., 1997 and 2019). The distinct ocean pCO2 anomaly is attributed to an amplified warming and an unprecedented weakening Indonesian Throughflow under the influence of co‐occurrence of positive IOD and extreme El Niño in 2015. The amplified warming drives higher ocean pCO2 in the western and central Indian Ocean, while the ITF transports anomalously high ocean pCO2 water from the Pacific Ocean to the southeastern Indian Ocean. This newly identified ocean carbon response provides deeper insights into the Indian Ocean carbon interannual variability.

中文翻译：

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2015 年印度洋碳吸收减弱：全流域变暖加剧和印度尼西亚流量减少的作用

2015年，印度洋的二氧化碳浓度异常减弱2吸收，凸显了海洋碳汇的强烈年际变化。通过利用多个海洋二氧化碳2分压 （p一氧化碳2）数据和最先进的海洋生物地球化学模型，我们表明 2015 年海洋二氧化碳2异常现象的特点是整个盆地范围内海洋的放大p一氧化碳2，与海洋不同p一氧化碳2对其他印度洋偶极子事件（例如 1997 年和 2019 年）的响应。独特的海洋p一氧化碳2异常现象归因于2015年正IOD和极端厄尔尼诺现象同时发生的影响下，变暖加剧和印度尼西亚穿流史无前例的减弱。变暖加剧导致海平面上升p一氧化碳2在印度洋西部和中部，而 ITF 运输异常高的海洋p一氧化碳2水从太平洋流向东南印度洋。这种新发现的海洋碳响应提供了对印度洋碳年际变化的更深入的了解。