ACE-1 - Southern Hemisphere marine aerosol characterisation experiment

Metadata record for data from ASAC Project 829
See the link below for public details on this project.

From the abstract of one of the referenced papers:

During the intensive field operations period (November 15 to December 14, 1995) of the First Aerosol Characterisation Experiment (ACE 1) cold front activity was generally above average, resulting in below average temperatures, pressures, and rainfall. The principal cause was the presence for much of the experiment of a long wave trough. This trough was mobile, traversing the ACE area during the project, with some warm anomalies evident in teh areas under the influence of the long wave ridges. There is evidence of greater convective activity than normal, possibly leading to a slightly deeper than average mixing layer. A greater west to northwesterly component to the air flow than average during November appears to have led to higher than average concentrations of radon and particles in the clean, marine or 'baseline'; sector at Cape Grim (190 degrees to 280 degrees). This is likely to have resulted from inclusion of continental air from western parts of the Australian mainland in the baseline sector winds. Although aerosol-bound sulfur species were generally near their normal concentrations across the ACE 1 area, the overall pattern including atmospheric dimethylsulfide suggest slightly higher than usual sulfur species levels in the southern part of the region and lower concentrations in the northern part during November. This could be related to changes in marine biogenic productivity, air-sea exchange, or atmospheric removal. In December, the changing long wave pattern brought an increase in south and southwesterly flow over the entire region. The baseline sector became less affected by continental species, but it appears that the colder conditions brought by this pattern have led to lower than usual atmospheric concentrations of biogenic species, as the region went into one of the coldest summers on record.

ASAC项目829号数据集元数据记录
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以下引自一篇相关论文的摘要：

在第一次气溶胶特性表征实验（First Aerosol Characterisation Experiment，ACE 1）的密集野外作业周期（1995年11月15日至12月14日）内，区域冷锋活动整体强于常年平均，导致气温、气压与降水量均低于常年均值。本次异常气象条件的主因是实验大部分时段区域内长期存在长波槽。该长波槽具有移动性，在项目实施期间穿越ACE 1实验区域，长波脊影响区域内则出现显著暖异常。观测证据表明，区域对流活动较常态更为活跃，可能使得混合层深度略高于常年平均。11月期间，区域气流以偏西至偏西北风为主，且强度高于常年，这使得格雷角（Cape Grim）清洁海洋本底监测区域（190°至280°方位）内的氡气与颗粒物浓度均高于常年均值，该现象大概率源于本底区域的风场裹挟了澳大利亚大陆西部的大陆气团。

尽管ACE 1实验区域内的气溶胶结合态硫组分整体浓度接近常态，但结合大气中二甲基硫（dimethylsulfide, DMS）的整体分布特征来看，11月期间区域南部的硫组分浓度略高于常规水平，而北部则相对偏低。该分布格局可能与海洋生物源生产力变化、海气交换过程或大气清除过程的改变有关。12月，长波环流格局发生变化，区域整体转为偏南至偏西南气流。本底区域受大陆源组分的影响减弱，但由于该区域进入了有记录以来最冷的夏季之一，此次环流格局带来的低温环境使得区域内生物源大气组分的浓度低于常规水平。