Simulated Variation Characteristics of Oceanic CO2 Uptake, Surface Temperature, and Acidification in Zhejiang Province, China
Simulated Variation Characteristics of Oceanic CO2 Uptake, Surface Temperature, and Acidification in Zhejiang Province, China
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DOI：
10.3389/fphy.2021.718968
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发表时间：
2021-08
期刊：
影响因子：
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通讯作者：
Kuo Wang;Han Zhang;Gaojing Fan;Zhengquan Li;Zhenlong Yu;Peipei Liu
中科院分区：
文献类型：
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作者：
Kuo Wang;Han Zhang;Gaojing Fan;Zhengquan Li;Zhenlong Yu;Peipei Liu
自前工业化时代以来，大气中二氧化碳含量不断增加，通过温室效应导致全球变暖。海洋固碳减缓全球变暖；另一方面，海洋二氧化碳的吸收会降低海水的pH值，这被称为海洋酸化。我们进行地球系统模型模拟，以评估浙江近海的海洋二氧化碳吸收、表面温度和酸化情况，浙江近海是最容易遭受海洋灾害的地区之一。近40年来，大气中CO2浓度增加了71 ppm，浙江近海海面温度（SST）以0.16℃/10a的速度上升。浙江近海海洋CO2累计吸收量为0.3 Pg C，导致近十年海面氢离子浓度增加20%，酸化速度加快。 2020-2040年，四种RCP情景下，浙江近海海温上升0.3-0.5℃，累计海洋碳汇为0.150-0.165 Pg C。相对于RCP2.6，RCP8.5下浙江近海表面pH值下降了一倍。此外，模拟结果表明，CO2情景与海洋碳循环之间的关系是非线性的，这表明如果要在较高CO2浓度情景下缓解浙江近海海洋酸化，可能需要进一步减少人为CO2排放。本研究量化了浙江近海海洋气候和碳循环场的变化特征，为研究海洋碳循环和气候系统对海洋碳汇的响应提供了新的见解。
Since preindustrial times, atmospheric CO2 content increased continuously, leading to global warming through the greenhouse effect. Oceanic carbon sequestration mitigates global warming; on the other hand, oceanic CO2 uptake would reduce seawater pH, which is termed ocean acidification. We perform Earth system model simulations to assess oceanic CO2 uptake, surface temperature, and acidification for Zhejiang offshore, one of the most vulnerable areas to marine disasters. In the last 40 years, atmospheric CO2 concentration increased by 71 ppm, and sea surface temperature (SST) in Zhejiang offshore increased at a rate of 0.16°C/10a. Cumulative oceanic CO2 uptake in Zhejiang offshore is 0.3 Pg C, resulting in an increase of 20% in sea surface hydrogen ion concentration, and the acidification rate becomes faster in the last decade. During 2020–2040, under four RCP scenarios, SST in Zhejiang offshore increases by 0.3–0.5°C, whereas cumulative ocean carbon sequestration is 0.150–0.165 Pg C. Relative to RCP2.6, the decrease of surface pH in Zhejiang offshore is doubled under RCP8.5. Furthermore, simulated results show that the relationship between CO2 scenario and oceanic carbon cycle is nonlinear, which hints that deeper reduction of anthropogenic CO2 emission may be needed if we aim to mitigate ocean acidification in Zhejiang offshore under a higher CO2 concentration scenario. Our study quantifies the variation characteristics of oceanic climate and carbon cycle fields in Zhejiang offshore, and provides new insight into the responses of oceanic carbon cycle and the climate system to oceanic carbon sequestration.