PM_2.5, or fine particulate matter, is a category of air pollutant consisting of particles with effective aerodynamic diameter equal to or less than 2.5 μm. These particles have been linked to human health impacts as well as regional haze, visibility, and climate change issues. Due to cost and space restrictions, the U.S. Environmental Protection Agency monitoring network remains spatially sparse. To increase the spatial resolution of monitoring, previous studies have used satellite data to estimate ground‐level PM concentrations, despite these estimates being associated with moderate to large uncertainties when relating a column measure of aerosol (aerosol optical depth) with surface measurements. To this end, we discuss a low‐cost air quality monitor (LCAQM) network deployed in California. In this study, we present an application of LCAQM and satellite data for quantifying the impact of wildfires in California during October 2017. The impacts of fires on PM_2.5 concentration at varying temporal (hourly, daily, and weekly) and spatial (local to regional) scales have been evaluated. Comparison between low‐cost air quality sensors and reference‐grade air quality instruments shows expected performance with moderate to high uncertainties. The LCAQM measurements, in the absence of federal equivalent method data, were also found to be very useful in developing statistical models to convert aerosol optical depth into PM_2.5 with performance of satellite‐derived PM_2.5, similar to that obtained using the federal equivalent method data. This paper also highlights challenges associated with both LCAQM and satellite‐based PM_2.5 measurements, which require further investigation and research.

中文翻译：

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加州大火对当地和地区空气质量的影响：低成本传感器网络和卫星观测的作用。

下午_2.5或细颗粒物是一类空气污染物，由有效空气动力学直径等于或小于2.5μm的颗粒组成。这些颗粒与人类健康影响以及区域霾，能​​见度和气候变化问题有关。由于成本和空间的限制，美国环境保护局的监控网络在空间上仍然稀疏。为了提高监测的空间分辨率，尽管将柱状气溶胶测量值（气溶胶光学深度）与表面测量值相关联，但这些估计值具有中等到较大的不确定性，但先前的研究已使用卫星数据来估计地面PM浓度。为此，我们讨论了在加利福尼亚州部署的低成本空气质量监控器（LCAQM）网络。在这个研究中，_2.5评估了不同时间（每小时，每天和每周）和空间（局部到区域）尺度下的浓度。低成本空气质量传感器与参考级空气质量仪器之间的比较表明，预期性能具有中等到高度的不确定性。还发现，在缺乏联邦等效方法数据的情况下，LCAQM测量对于建立统计模型将气溶胶光学深度转换为具有卫星衍生的PM _2.5性能的PM _2.5十分有用，类似于使用联邦等效方法获得的数据数据。本文还重点介绍了与LCAQM和基于卫星的PM _2.5测量相关的挑战，这需要进一步的研究。