The sulfur cycle at high-southern latitudes in the LMD-ZT General Circulation Model
The sulfur cycle at high-southern latitudes in the LMD-ZT General Circulation Model
复制标题
LMD-ZT大气环流模型中南高纬度地区的硫循环
DOI：
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发表时间：
2002
期刊：
影响因子：
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通讯作者：
M. Pham
中科院分区：
文献类型：
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作者：
E. Cosme;C. Genthon;P. Martinerie;O. Boucher;M. Pham
[1]这项建模研究的动机是最近发表的南极洲二甲基硫醚（DMS）和二甲基亚砜（DMSO）的全年记录，完成了硫酸盐和甲磺酸（MSA）的可用系列。硫化学已被纳入气象实验室动态变焦示踪剂（LMD-ZT）大气环流模型（AGCM）中，具有高分辨率和改进的南半球高纬度物理特性。该模型通过排放、运输、湿和干沉积以及气相和水相中的化学来预测六种主要硫物质的浓度。与在空气和雪或冰中的测量结果以及在南高纬度和中纬度的其他模拟研究结果相比，模型结果基本上是现实的。在夏季，大气MSA浓度被低估，DMSO浓度被高估，反映了缺乏DMSO异质汇导致MSA。各种最近发表的估计，这个汇的速率的实验报告。虽然在这项工作中没有纠正，其他缺陷被确定和讨论：DMS浓度被低估，在冬季，MSA和非海盐（NSS）硫酸盐浓度可能被低估，在南极，在模型中使用的沉积计划可能不适应极地地区，该模型没有充分再现年际变化。海洋二甲基硫源对这些区域硫的变化有重大贡献。模型结果表明，在南极洲中部的大部分地区，地面大气DMS浓度在冬季大于夏季。在南半球高纬度地区，DMS和DMSO的含量很高，二氧化硫（SO2）的主要化学汇是臭氧（O3）的水氧化，而过氧化氢（H2 O2）的氧化在全球范围内占主导地位。提供了一个全面的模拟南极洲的硫收支。
[1] This modeling study was motivated by the recent publication of year-round records of dimethylsulfide (DMS) and dimethylsulfoxide (DMSO) in Antarctica, completing the available series of sulfate and methanesulfonic acid (MSA). Sulfur chemistry has been incorporated in the Laboratoire de Meteorologie Dynamique-Zoom Tracers (LMD-ZT) Atmospheric General Circulation Model (AGCM), with high-resolution and improved physics at high-southern latitudes. The model predicts the concentration of six major sulfur species through emissions, transport, wet and dry deposition, and chemistry in both gas and aqueous phases. Model results are broadly realistic when compared with measurements in air and snow or ice, as well as to results of other modeling studies, at high- and middle-southern latitudes. Atmospheric MSA concentrations are underestimated and DMSO concentrations are overestimated in summer, reflecting the lack of a DMSO heterogeneous sink leading to MSA. Experiments with various recently published estimates of the rate of this sink are reported. Although not corrected in this work, other defects are identified and discussed: DMS concentrations are underestimated in winter, MSA and non-sea-salt (nss) sulfate concentrations may be underestimated at the South Pole, the deposition scheme used in the model may not be adapted to polar regions, and the model does not adequately reproduces interannual variability. Oceanic DMS sources have a major contribution to the variability of sulfur in these regions. The model results suggest that in a large part of central Antarctica ground-level atmospheric DMS concentrations are larger in winter than in summer. At high-southern latitudes, high loads of DMS and DMSO are found and the main chemical sink of sulfur dioxide (SO2) is aqueous oxidation by ozone (O3), whereas oxidation by hydrogen peroxide (H2O2) dominates at the global scale. A comprehensive modeled sulfur budget of Antarctica is provided.