Department of Mechanical Engineering , University of California, Berkeley , Berkeley , California 94720 , United States.
Energy Technologies Area , Lawrence Berkeley National Laboratory , Berkeley , California 94720 , United States.
Environ Sci Technol. 2019 Jul 2;53(13):7564-7573. doi: 10.1021/acs.est.9b00282. Epub 2019 Jun 18.
Ambient particulate matter (PM) pollution is a major environmental health risk in urban areas. Dense networks of low-cost air quality sensors are emerging to characterize the spatially heterogeneous concentrations that are typical of urban settings, but are not adequately captured using traditional regulatory monitors at central sites. In this study, we present the 100×100 BC Network, a 100-day deployment of low-cost black carbon (BC) sensors across 100 locations in West Oakland, California. This 15 km community is surrounded by freeways and affected by emissions associated with local port and industrial activities. We assess the reliability of the sensor hardware and data collection systems, and identify modes of failure to both quantify and qualify network performance. We illustrate how dynamic, local emission sources build upon background BC concentrations. BC concentrations varied sharply over short distances (∼100 m) and timespans (∼1 hour), depending on surrounding land use, traffic patterns, and downwind distance from pollution sources. Strong BC concentration fluctuations were periodically observed over the diurnal and weekly cycles, reflecting the impact of localized traffic emissions and industrial facilities in the neighborhood. Overall, the results demonstrate how distributed sensor networks can reveal the complex spatiotemporal dynamics of combustion-related air pollution within urban neighborhoods.
环境颗粒物（PM）污染是城市地区的主要环境健康风险。密集的低成本空气质量传感器网络正在出现，以描述城市环境中典型的空间异质浓度，但传统的中央站点监管监测器无法充分捕捉到这些浓度。在本研究中，我们介绍了 100×100BC 网络，这是在加利福尼亚州奥克兰西部的 100 个地点进行的为期 100 天的低成本黑碳（BC）传感器部署。这个 15 公里的社区被高速公路环绕，受到与当地港口和工业活动相关的排放物的影响。我们评估了传感器硬件和数据采集系统的可靠性，并确定了故障模式，以量化和定性网络性能。我们说明了动态的本地排放源如何在背景 BC 浓度的基础上增加浓度。BC 浓度在短距离（约 100 米）和短时间跨度（约 1 小时）内变化很大，具体取决于周围的土地利用、交通模式以及与污染源的下风距离。在昼夜和每周周期中，周期性地观察到强烈的 BC 浓度波动，反映了局部交通排放和附近工业设施的影响。总的来说，结果表明分布式传感器网络如何揭示城市社区内与燃烧相关的空气污染的复杂时空动态。
