Global atmospheric sulfur budget under volcanically quiescent conditions: Aerosol‐chemistry‐climate model predictions and validation
Global atmospheric sulfur budget under volcanically quiescent conditions: Aerosol‐chemistry‐climate model predictions and validation
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火山静止条件下的全球大气硫收支：气溶胶化学气候模型预测和验证
DOI：
10.1002/2014jd021985
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发表时间：
2015
期刊：
影响因子：
--
通讯作者：
T. Peter
中科院分区：
文献类型：
--
作者：
J. Sheng;D. Weisenstein;B. Luo;E. Rozanov;A. Stenke;J. Anet;H. Bingemer;T. Peter
使用气溶胶-化学-气候耦合模型 SOCOL-AER 研究了全球大气硫收支及其排放依赖性。气溶胶模块包括气态和水态硫化学以及综合微物理学。颗粒分布由半径从 0.39 nm 到 3.2 μm 的 40 个尺寸箱解析，包括尺寸相关的颗粒组成。气候模型所需的气溶胶辐射特性是通过气溶胶模块在线计算的。该模型成功地再现了非火山条件下平流层气溶胶的主要特征，包括与平流层气溶胶和气体实验 II (SAGE II) 和卤素掩星实验相比的气溶胶消光，以及与现场测量相比的尺寸分布。计算得出的平流层气溶胶含量为 109 Gg 硫，与基于 SAGE II 的估计值 (112 Gg) 相符。就通过对流层顶的通量而言，平流层气溶胶层由约 43% 初级对流层气溶胶、28% SO2、23% 硫化碳 (OCS)、4% H2S 和 2% 二甲硫醚 (DMS) 组成。关闭短寿命物质 SO2、H2S 和 DMS 的排放表明，仅 OCS 仍占原始平流层气溶胶负荷的约 56%。进一步的敏感性模拟表明，由于西太平洋地区的深层对流，中国和印度人为二氧化硫排放量的预期增加对平流层气溶胶的影响比西欧或美国的同样增加的影响更大。然而，即使中国和印度的排放量增加一倍，预计平流层背景气溶胶负荷也仅增加 9%。相比之下，小到中度的火山喷发，例如 2011 年的纳布罗火山喷发，很容易使平流层气溶胶负荷增加一倍。
The global atmospheric sulfur budget and its emission dependence have been investigated using the coupled aerosol‐chemistry‐climate model SOCOL‐AER. The aerosol module comprises gaseous and aqueous sulfur chemistry and comprehensive microphysics. The particle distribution is resolved by 40 size bins spanning radii from 0.39 nm to 3.2 μm, including size‐dependent particle composition. Aerosol radiative properties required by the climate model are calculated online from the aerosol module. The model successfully reproduces main features of stratospheric aerosols under nonvolcanic conditions, including aerosol extinctions compared to Stratospheric Aerosol and Gas Experiment II (SAGE II) and Halogen Occultation Experiment, and size distributions compared to in situ measurements. The calculated stratospheric aerosol burden is 109 Gg of sulfur, matching the SAGE II‐based estimate (112 Gg). In terms of fluxes through the tropopause, the stratospheric aerosol layer is due to about 43% primary tropospheric aerosol, 28% SO2, 23% carbonyl sulfide (OCS), 4% H2S, and 2% dimethyl sulfide (DMS). Turning off emissions of the short‐lived species SO2, H2S, and DMS shows that OCS alone still establishes about 56% of the original stratospheric aerosol burden. Further sensitivity simulations reveal that anticipated increases in anthropogenic SO2 emissions in China and India have a larger influence on stratospheric aerosols than the same increase in Western Europe or the U.S., due to deep convection in the western Pacific region. However, even a doubling of Chinese and Indian emissions is predicted to increase the stratospheric background aerosol burden only by 9%. In contrast, small to moderate volcanic eruptions, such as that of Nabro in 2011, may easily double the stratospheric aerosol loading.