Atmospheric sulfur cycling in the southeastern Pacific – longitudinal distribution, vertical profile, and diel variability observed during VOCALS-REx
Atmospheric sulfur cycling in the southeastern Pacific – longitudinal distribution, vertical profile, and diel variability observed during VOCALS-REx
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东南太平洋的大气硫循环——VOCALS-REx 期间观测到的纵向分布、垂直剖面和昼夜变化
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发表时间：
2011
期刊：
影响因子：
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通讯作者：
J. Collett
中科院分区：
文献类型：
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作者：
Mingxi Yang;B. Huebert;B. Blomquist;S. Howell;L. Shank;C. McNaughton;A. Clarke;L. Hawkins;L. Russell;D. Covert;D. Coffman;T. Bates;P. Quinn;N. Zagorac;A. Bandy;S. Szoeke;P. Zuidema;S. Tucker;W. Brewer;K. Benedict;J. Collett
抽象的。海洋排放的二甲基硫（DMS）是二氧化硫（SO 2）和非海盐硫酸盐气溶胶（SO 4 2−）的生物前体气体。在2008年的VAMOS-海洋-云-大气-陆地研究区域实验（VOCALS-REx）期间，在智利和秘鲁沿海的东南太平洋（SEP）部署了多个仪器平台，以研究气溶胶和层积云之间的联系。我们在这里介绍NOAA船罗纳德H。Brown和NSF/NCAR C-130飞机沿沿着~20° S从海岸（70° W）到遥远的海洋大气层（85° W）。虽然由于人为影响，SO 4 2−和SO2浓度在沿海海洋边界层（MBL）中明显高于背景水平（分别为约800和80 pptv），但它们的浓度在78° W以西迅速下降（约100和25 pptv）。在偏远地区，来自自由对流层（FT）的夹带以0.05 ± 0.02 μmoles m −2 day −1的速率增加了MBL SO 2负荷，以0.5 ± 0.3 μmoles m −2 day −1的速率增加了稀释的MBL SO 4 2负荷，而海-气二甲基硫通量（3.8 ± 0.4 μmoles m −2 day −1）仍然是MBL硫质量的主要来源。云中氧化被认为是SO2去除和原位SO 4 2−产生的最重要机制。在遥远的MBL中，表面SO 4 2−浓度显示出明显的昼夜变化，在日落后的最初几个小时内迅速增加，并在一天的其余时间内衰减。我们的理论是，SO 4 2-的增加是由于夜间MBL的重新耦合，混合了云处理的空气，而解耦和零星的降水清除是白天SO 4 2-下降的原因。
Abstract. Dimethylsulfide (DMS) emitted from the ocean is a biogenic precursor gas for sulfur dioxide (SO 2 ) and non-sea-salt sulfate aerosols (SO 4 2− ). During the VAMOS-Ocean-Cloud-Atmosphere-Land Study Regional Experiment (VOCALS-REx) in 2008, multiple instrumented platforms were deployed in the Southeastern Pacific (SEP) off the coast of Chile and Peru to study the linkage between aerosols and stratocumulus clouds. We present here observations from the NOAA Ship Ronald H. Brown and the NSF/NCAR C-130 aircraft along ~20° S from the coast (70° W) to a remote marine atmosphere (85° W). While SO 4 2− and SO 2 concentrations were distinctly elevated above background levels in the coastal marine boundary layer (MBL) due to anthropogenic influence (~800 and 80 pptv, respectively), their concentrations rapidly decreased west of 78° W (~100 and 25 pptv). In the remote region, entrainment from the free troposphere (FT) increased MBL SO 2 burden at a rate of 0.05 ± 0.02 μmoles m −2 day −1 and diluted MBL SO 4 2 burden at a rate of 0.5 ± 0.3 μmoles m −2 day −1 , while the sea-to-air DMS flux (3.8 ± 0.4 μmoles m −2 day −1 ) remained the predominant source of sulfur mass to the MBL. In-cloud oxidation was found to be the most important mechanism for SO 2 removal and in situ SO 4 2− production. Surface SO 4 2− concentration in the remote MBL displayed pronounced diel variability, increasing rapidly in the first few hours after sunset and decaying for the rest of the day. We theorize that the increase in SO 4 2− was due to nighttime recoupling of the MBL that mixed down cloud-processed air, while decoupling and sporadic precipitation scavenging were responsible for the daytime decline in SO 4 2− .
影响因子：
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作者：
Mingxi Yang;B. Blomquist;C. Fairall;S. Archer;B. Huebert
通讯作者：
Mingxi Yang;B. Blomquist;C. Fairall;S. Archer;B. Huebert