The new generation GISS climate model includes fully interactive chemistry related to ozone in historical and future simulations, and interactive methane in future simulations. Evaluation of ozone, its tropospheric precursors, and methane shows that the model captures much of the large-scale spatial structure seen in recent observations. While the model is much improved compared with the previous chemistry-climate model, especially for ozone seasonality in the stratosphere, there is still slightly too rapid stratospheric circulation, too little stratosphere-to-troposphere ozone flux in the Southern Hemisphere and an Antarctic ozone hole that is too large and persists too long. Quantitative metrics of spatial and temporal correlations with satellite datasets as well as spatial autocorrelation to examine transport and mixing are presented to document improvements in model skill and provide a benchmark for future evaluations. The difference in radiative forcing (RF) calculated using modeled tropospheric ozone versus tropospheric ozone observed by TES is only 0.016 W m?2. Historical 20th Century simulations show a steady increase in whole atmosphere ozone RF through 1970 after which there is a decrease through 2000 due to stratospheric ozone depletion. Ozone forcing increases throughout the 21st century under RCP8.5 owing to a projected recovery of stratospheric ozone depletion and increases in methane, but decreases under RCP4.5 and 2.6 due to reductions in emissions of other ozone precursors. RF from methane is 0.05 to 0.18 W m?2 higher in our model calculations than in the RCP RF estimates. The surface temperature response to ozone through 1970 follows the increase in forcing due to tropospheric ozone. After that time, surface temperatures decrease as ozone RF declines due to stratospheric depletion. The stratospheric ozone depletion also induces substantial changes in surface winds and the Southern Ocean circulation, which may play a role in a slightly stronger response per unit forcing during later decades. Tropical precipitation shifts south during boreal summer from 1850 to 1970, but then shifts northward from 1970 to 2000, following upper tropospheric temperature gradients more strongly than those at the surface.
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机译：新一代GISS气候模型包括与历史和未来模拟中的臭氧相关的完全交互化学，并在未来模拟中的互动甲烷。臭氧，其对流层前体和甲烷的评价表明，该模型捕获了最近观察结果中看到的大量大规模空间结构。虽然该模型与先前的化学气候模型相比有很大改善，但特别是对于平流层中的臭氧季节性，仍然存在略微过于快速的平坦流循环，南半球和南极臭氧孔中的平流层到对流层臭氧通量太少太大了，持续时间太长了。展示与卫星数据集的空间和时间相关性的定量度量以及用于检查传输和混合的空间自相关，以文档提高模型技能，并为未来的评估提供基准。使用模型的对流层臭氧计算的辐射强制（RF）与TES观察到的对流层臭氧计算的差异仅为0.016 W m？2。历史20世纪模拟在1970年至1970年至1970年的全部大气臭氧稳定上升，由于平面臭氧耗尽，通过2000次减少。由于平流层臭氧耗竭的投影回收率，臭氧强迫在整个21世纪下增加，但由于甲烷增加，但由于其他臭氧前体的排放减少，甲烷下降，但甲烷下降，但在RCP4.5和2.6下降。在我们的模型计算中，来自甲烷的RF在0.05至0.18W m？2比RCP射频估计中更高。对臭氧到1970的表面温度响应遵循由于对流层臭氧引起的迫使。此后，随着臭氧耗尽由于臭氧的射率下降，表面温度降低。平流层臭氧耗尽也诱导表面风和南海循环的大量变化，这可能在晚些时候在每单位强迫略微较强的反应中发挥作用。从1850年到1970年，热带降水在北方夏季移动南方，但随后从1970年到2000年向北转移，继上层温度梯度比表面上更强烈。
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