Dolislager Leon J, Motallebi Nehzat
a Atmospheric Processes Research Section , California Air Resources Board , Sacramento , California , USA.
J Air Waste Manag Assoc. 1999 Sep;49(9):45-56. doi: 10.1080/10473289.1999.10463898.
The size, composition, and concentration of particulate matter (PM) vary with location and time. Several monitoring/sampling programs are operated in California to characterize PM less than 2.5 and 10 µm in aerodynamic diameter (PM and PM). This paper presents a broad summary of the spatial and temporal variations observed in ambient PM and PM concentrations in California. Many areas that have high PM concentrations also have relatively high PM concentrations, and data indicate that a significant portion of the PM air quality problem is caused by PM To develop effective plans for attaining the ambient PM standards, improved understanding of these unique problems is needed. Since 1989, pollution control efforts-whether specifically targeted for particulate matter or indirectly via controls on gaseous emissions-have caused annual average PM and PM concentrations to decline at most sites in California.
颗粒物（PM）的大小、成分和浓度随地点和时间而变化。加利福尼亚州开展了若干监测/采样项目，以表征空气动力学直径小于2.5微米和10微米的颗粒物（PM₂.₅和PM₁₀）。本文对加利福尼亚州环境空气中PM₂.₅和PM₁₀浓度的时空变化进行了全面总结。许多PM₂.₅浓度高的地区PM₁₀浓度也相对较高，数据表明，PM₂.₅是造成大部分PM空气质量问题的原因。为制定实现环境PM标准的有效计划，需要更好地了解这些独特问题。自1989年以来，无论是专门针对颗粒物的污染控制措施，还是通过控制气体排放的间接措施，都已使加利福尼亚州大多数监测点的PM₂.₅和PM₁₀年均浓度有所下降。
