Tropospheric carbon monoxide over the Pacific during HIPPO: Two-way coupled simulation of GEOS-Chem and its multiple nested models
Tropospheric carbon monoxide over the Pacific during HIPPO: Two-way coupled simulation of GEOS-Chem and its multiple nested models
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HIPPO 期间太平洋上空的对流层一氧化碳：GEOS-Chem 及其多个嵌套模型的双向耦合模拟
DOI：
10.5194/acp-14-12649-2014
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发表时间：
2014-12
影响因子：
6.3
通讯作者：
Lin Zhang
中科院分区：
文献类型：
--
作者：
Jintai Lin;Ye Kuang;Dongwei Yang;Lin Zhang
摘要。全球化学输运模式（CTMs）被广泛用于研究全球尺度的空气污染和输运。这些模型受限于粗糙的水平分辨率，不允许对污染源区域的小尺度非线性过程进行详细表示。本文将全球GEOS-Chem CTM及其三种高分辨率嵌套模式结合起来，模拟了2009年至2011年期间5次高性能机载环境研究平台（HIAPER）极对极观测（HIPPO）活动期间太平洋对流层一氧化碳（CO）。我们开发了一种双向耦合器，北京大学耦合器（PKUCPL），允许全球模型（2.5°长）之间的化学成分交换和相互作用。× 2°纬度)和三个嵌套模型(0.667°长。× 0.5°)，覆盖亚洲、北美和欧洲。耦合器获得嵌套模型结果，对各自嵌套域中的全局模型仿真进行修正，同时获取全局模型结果，为嵌套模型提供横向边界条件。与单独的全球模式相比，双向耦合模拟导致嵌套区域CO浓度增加。敏感性试验表明，这种增强是由于CO、氮氧化物和非甲烷挥发性有机化合物的空间分布、自然排放对气象的依赖性以及其他分辨率依赖性过程的代表性得到改善。CO的相对较长的寿命使得增强可以在全球范围内积累和携带。结果表明，双向耦合模拟使2009年全球对流层平均CO浓度增加了10.4%，其中北半球的增加幅度更大，达到13.3%。巧合的是，全球对流层平均羟基自由基（OH）减少4.2%，导致甲基氯仿寿命（MCF；通过与对流层OH的反应）增加4.2%。得到的CO和OH含量和MCF寿命更接近基于观测的估计。全球模式和双向耦合模式都捕获了太平洋上空HIPPO CO的一般时空格局。双向耦合模拟更接近HIPPO CO，在9 km以下的平均偏差为1.1 ppb(1.4%)，而全球模型的偏差为- 7.2 ppb（- 9.2%）。这种改善在北太平洋上空最为明显。我们的测试模拟表明，全球模式单独可以类似于双向耦合模拟（特别是在4公里以下），通过将其全球CO排放量增加HIPPO-1和HIPPO-3 15%， HIPPO-2和HIPPO-4 25%， HIPPO-5 35%。这对于单独使用全球模式来限制CO排放具有重要意义。因此，双向耦合模拟是研究主要人为源区大气污染物全球影响的一种显著改进的模式工具。
Abstract. Global chemical transport models (CTMs) are used extensively to study air pollution and transport at a global scale. These models are limited by coarse horizontal resolutions that do not allow for a detailed representation of small-scale nonlinear processes over the pollutant source regions. Here we couple the global GEOS-Chem CTM and its three high-resolution nested models to simulate the tropospheric carbon monoxide (CO) over the Pacific Ocean during five High-performance Instrumented Airborne Platform for Environmental Research (HIAPER) Pole-to-Pole Observations (HIPPO) campaigns between 2009 and 2011. We develop a two-way coupler, the PeKing University CouPLer (PKUCPL), allowing for the exchange and interaction of chemical constituents between the global model (at 2.5° long. × 2° lat.) and the three nested models (at 0.667° long. × 0.5° lat.) covering Asia, North America, and Europe. The coupler obtains nested model results to modify the global model simulation within the respective nested domains, and simultaneously acquires global model results to provide lateral boundary conditions (LBCs) for the nested models. Compared to the global model alone, the two-way coupled simulation results in enhanced CO concentrations in the nested domains. Sensitivity tests suggest the enhancement to be a result of improved representation of the spatial distributions of CO, nitrogen oxides, and non-methane volatile organic compounds, the meteorological dependence of natural emissions, and other resolution-dependent processes. The relatively long lifetime of CO allows for the enhancement to be accumulated and carried across the globe. We found that the two-way coupled simulation increased the global tropospheric mean CO concentrations in 2009 by 10.4%, with a greater enhancement at 13.3% in the Northern Hemisphere. Coincidently, the global tropospheric mean hydroxyl radical (OH) was reduced by 4.2%, resulting in a 4.2% enhancement in the methyl chloroform lifetime (MCF; via reaction with tropospheric OH). The resulting CO and OH contents and MCF lifetime are closer to observation-based estimates. Both the global and the two-way coupled models capture the general spatiotemporal patterns of HIPPO CO over the Pacific. The two-way coupled simulation is much closer to HIPPO CO, with a mean bias of 1.1 ppb (1.4%) below 9 km compared to the bias at −7.2 ppb (−9.2%) for the global model alone. The improvement is most apparent over the North Pacific. Our test simulations show that the global model alone could resemble the two-way coupled simulation (especially below 4 km) by increasing its global CO emissions by 15% for HIPPO-1 and HIPPO-3, by 25% for HIPPO-2 and HIPPO-4, and by 35% for HIPPO-5. This has important implications for using the global model alone to constrain CO emissions. Thus, the two-way coupled simulation is a significantly improved model tool for studying the global impacts of air pollutants from major anthropogenic source regions.
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影响因子：
5.2
作者：
Jintai Lin;D. Wuebbles;Xin‐Zhong Liang
通讯作者：
Jintai Lin;D. Wuebbles;Xin‐Zhong Liang
影响因子：
6.3
作者：
Lam, Y. F.;Fu, J. S.
通讯作者：
Fu, J. S.
影响因子：
56.9
作者：
Hongbin Yu;L. Remer;M. Chin;H. Bian;Q. Tan;T. Yuan;Yan Zhang
通讯作者：
Hongbin Yu;L. Remer;M. Chin;H. Bian;Q. Tan;T. Yuan;Yan Zhang
影响因子：
18.3
作者：
Kort, E. A.;Wofsy, S. C.;Zondlo, M. A.
通讯作者：
Zondlo, M. A.
影响因子：
5
作者：
Lin, Jin-Tai;McElroy, Michael B.
通讯作者：
McElroy, Michael B.