Impact of Unmitigated HFC Emissions on Stratospheric Ozone at the End of the 21st Century as Simulated by Chemistry‐Climate Models
Impact of Unmitigated HFC Emissions on Stratospheric Ozone at the End of the 21st Century as Simulated by Chemistry‐Climate Models
复制标题
化学气候模型模拟 21 世纪末未缓解的 HFC 排放对平流层臭氧的影响
DOI：
10.1029/2021jd035307
复制
发表时间：
2021
期刊：
影响因子：
--
通讯作者：
Yamashita Yousuke
中科院分区：
文献类型：
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作者：
Dupuy Eric;Akiyoshi Hideharu;Yamashita Yousuke
氢氟碳化合物（HFC）已经越来越多地取代氯氟烃和氢氯氟烃。虽然它们的直接化学臭氧消耗潜力可以忽略不计，但作为强有力的温室气体，它们改变了大气温度和环流模式，从而间接影响平流层臭氧的恢复。测量和模型预测必须继续评估氢氟碳化合物限制措施，并评估氢氟碳化合物对大气辐射收支和平流层臭氧的长期影响。在这项研究中，我们提出了多成员集合模拟，旨在估计世纪末HFC对平流层温度，臭氧和环流变化的影响。我们比较了两个三维化学气候模型的模拟，使用相同的化学模块，但不同的物理方案。在低纬度和中纬度地区，两种模式的温度和臭氧响应相当，与以前的研究基本一致。氢氟碳化合物导致温度显著升高，最高可达10-20百帕，并导致臭氧垂直正负异常交替出现。我们解释了这种模式的垂直运动（低，中平流层）和温度（平流层上部）异常的竞争效应。在北方高纬度地区，与以前的研究和模型本身之间存在很大的差异，这归因于冬季波活动引起的臭氧异常的差异。从数量上看，我们发现HFC对臭氧总量的净正面影响很小。冬季极地平流层的最大异常小于1%。我们的研究结果表明，HFC数量的增加可能对本世纪内平流层臭氧的恢复产生有限的影响，极地地区的不确定性很大。
Hydrofluorocarbons (HFCs) have been increasingly replacing chlorofluorocarbons and hydrochlorofluorocarbons. Although their direct chemical ozone‐depleting potential is negligible, as potent greenhouse gases they modify atmospheric temperature and circulation patterns, thereby indirectly influencing stratospheric ozone recovery. Measurements and model projections must continue to evaluate HFC limitation measures and assess the long‐term impact of HFCs on the atmospheric radiation budget and stratospheric ozone. In this study, we present multi‐member ensemble simulations designed to estimate the impact of HFCs on stratospheric temperature, ozone and circulation changes at the end of the century. We compared simulations with and without HFCs for two three‐dimensional chemistry‐climate models that use the same chemistry module but different physical schemes. At low and mid‐latitudes, temperature and ozone responses were comparable for both models and in general agreement with previous studies. HFCs induced a marked temperature increase up to about 10–20 hPa and vertically alternating positive and negative ozone anomalies. We explained this pattern by competing effects of vertical motion (low and middle stratosphere) and temperature (upper stratosphere) anomalies. At northern high latitudes, there were strong discrepancies with previous studies and between the models themselves, attributed to differences in ozone anomalies caused by wave activity during winter. Quantitatively, we found a net positive, but small, HFC impact on total ozone amounts. Largest anomalies were less than 1% in the winter polar stratosphere. Our results indicate that increasing HFC amounts will likely have a limited impact on stratospheric ozone recovery within this century, with large uncertainty in the polar regions.