概括
北美东部的污染气溶受到当地的东北和遥远的中西部来源的影响. 虽然中西部的污染在特定事件中可能占主导地位,但东北部的污染源在长期内始终是重要的.
科学领域:
- 大气化学和空气质量研究.
- 环境科学和污染研究.
背景情况:
- 了解空气污染的来源对于有效的环境管理至关重要.
- 之前的研究表明,复杂的来源对北美大气中的气溶有所贡献.
研究的目的:
- 在北美东部区分本地和遥远的气溶污染源.
- 量化不同地区对硫酸盐和元素气溶成分的贡献.
主要方法:
- 从美国东北部多个地点收集的气溶样本的基本分析.
- 使用痕迹元素和硫酸盐分析进行区域分配.
- 夏季和冬季采样数据的比较.
主要成果:
- 确定了东北气溶的一致的"前景",并叠加了中西部气溶脉冲.
- 东北来源主要贡献了大多数元素,除了来自加拿大炼厂的和.
- 硫和主要来自中西部.
- 中西部和东北部的来源对气溶硫酸盐的贡献相对较大,尽管东北部的SO2排放量较低.
- 在1982年的污染事件中,这两个地区在罗德岛对硫酸盐的贡献相似,而中西部在佛蒙特州占主导地位.
结论:
- 虽然遥远的中西部来源影响东北地区的空气污染,并且在特定的事件中可以占主导地位,但更接近的东北地区的来源具有相似的长期意义.
- 该研究强调了区域和远程运输在塑造空气质量的复杂相互作用.
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