CROCUS Air Quality Dataset from the University of Illinois Chicago (UIC), July 2024

This dataset was collected by the measurement system in the Atmosphere, Climate, and Ecosystems (ACE) Lab at the University of Illinois Chicago (UIC) from July 12 to July 31, 2024, as part of the Community Research on Climate and Urban Science (CROCUS) Urban Integrated Field Laboratory (UIFL) project, led by Argonne National Laboratory. To enhance understanding of urban air quality dynamics in Chicago, and as part of the CROCUS 2024 Urban Canyon Intensive Observation Period (IOP), several instruments were set up to provide continuous measurements of air quality parameters in Chicago during July 2024. These measurements cover both aerosols and gas-phase species. It focuses on particle size distribution (2.5–478 nm) measured by two Scanning Mobility Particle Sizers (SMPS) at a 4-min resolution, total particle number concentrations at a 1-s resolution, and chemical composition from a High-Resolution Time-of-Flight Aerosol Mass Spectrometer (AMS) at a 1-min resolution. Key gas-phase species, including NO, NO₂, SO₂, and O₃, are measured at a 1-min resolution, along with high-resolution NO and dimethyl sulfide (DMS) data from a Chemical Ionization Mass Spectrometer (CIMS). Volatile organic compound (VOC) data for toluene, isoprene, and benzene are provided by a GC-PID with a time resolution of 25 minutes. The data are formatted as NetCDF (.nc) files, making them easily accessible using common software such as MATLAB, R, and Python. Each parameter is stored in an individual dataset, which includes detailed instrument information in the header, as well as the corresponding sample start time and concentration/distribution data for each sample.本数据集由伊利诺伊大学芝加哥分校（University of Illinois Chicago, UIC）大气、气候与生态实验室（Atmosphere, Climate, and Ecosystems Lab, ACE Lab）的测量系统于2024年7月12日至7月31日采集，作为阿贡国家实验室牵头的气候与城市科学共同体研究（Community Research on Climate and Urban Science, CROCUS）城市综合野外实验室（Urban Integrated Field Laboratory, UIFL）项目的一部分。为加深对芝加哥城市空气质量动态变化的理解，同时作为CROCUS 2024城市峡谷密集观测期（Urban Canyon Intensive Observation Period, IOP）的研究内容，研究团队布设多台仪器，于2024年7月对芝加哥的空气质量参数开展连续监测。本次监测覆盖气溶胶与气相物种两大类。本数据集重点包含以下观测内容：两台扫描迁移率粒径谱仪（Scanning Mobility Particle Sizers, SMPS）以4分钟分辨率采集粒径范围为2.5–478 nm的颗粒物粒径分布数据；以1秒分辨率采集总颗粒物数浓度数据；高分辨率飞行时间气溶胶质谱仪（High-Resolution Time-of-Flight Aerosol Mass Spectrometer, AMS）以1分钟分辨率采集颗粒物化学组成数据。关键气相物种包括一氧化氮（NO）、二氧化氮（NO₂）、二氧化硫（SO₂）与臭氧（O₃），均以1分钟分辨率开展监测；化学电离质谱仪（Chemical Ionization Mass Spectrometer, CIMS）可提供高分辨率的NO与二甲基硫（dimethyl sulfide, DMS）观测数据。采用气相色谱-光离子化检测器（GC-PID）以25分钟的时间分辨率，采集甲苯、异戊二烯与苯的挥发性有机物（Volatile Organic Compound, VOC）观测数据。本数据集采用NetCDF（.nc）文件格式存储，可通过MATLAB、R、Python等通用软件便捷读取。每个参数均单独存储为独立数据集，文件头中包含仪器的详细信息，同时附带每份样本对应的起始时间与浓度/分布数据。