Processed carbon mass loading data from DRI and Sunset analyzers

This dataset contains thermal-optical analysis (TOA) carbon data from an inter-laboratory comparison study described in the paper: Zhang, X., Trzepla, K., White, W., Raffuse, S., and Hyslop, N. P.: Intercomparison of thermal–optical carbon measurements by Sunset and Desert Research Institute (DRI) analyzers using the IMPROVE_A protocol, Atmos. Meas. Tech., 14, 3217–3231, https://doi.org/10.5194/amt-14-3217-2021, 2021.

Methods
Two sets of Chemical Speciation Network (CSN) carbon samples collected on 25mm diameter quartz filters were respectively analyzed by thermal-optical reflective analysis with the IMPROVE_A protocol. Set 1 consists of 303 CSN filters sampled in September and October 2007 that were previously analyzed by DRI with the DRI-2001 models in the year 2008. Set 2 consists of 4073 CSN samples and 622 CSN field blanks collected between May and September 2017, which were sequentially analyzed by the Sunset analyzers at UC Davis and by the DRI-2015 analyzers at DRI within a year after sample collection.

Sunset and DRI-2015 data are reported in mass loadings (μg/cm2). Sunset raw data were processed using a custom R computing package developed by UC Davis. DRI-2015 data were calculated by the program supplied by the manufacturer. DRI-2001 data from the archived 2007 CSN samples were downloaded from the EPA Air

Quality System (AQS) database (https://aqs.epa.gov/aqsweb/documents/data_api.html, last access: 28 April 2021). The concentration data (μgm-3) were converted to mass loadings (μg/cm2) using a nominal sample volume (33m3) and filter area (3.53 cm2) for direct comparison against the Sunset data.

本数据集包含来自一项实验室间比对研究的热光分析（thermal-optical analysis, TOA）碳数据，该研究详见论文：Zhang, X., Trzepla, K., White, W., Raffuse, S. 及 Hyslop, N. P.: 采用IMPROVE_A协议的Sunset与沙漠研究所（Desert Research Institute, DRI）分析仪热光碳测量比对，《Atmospheric Measurement Techniques》（Atmos. Meas. Tech.）, 14, 3217–3231, https://doi.org/10.5194/amt-14-3217-2021, 2021.

方法

采用基于IMPROVE_A协议的热光反射分析法，分别对两组以25mm直径石英滤膜采集的化学物种监测网（Chemical Speciation Network, CSN）碳样品进行分析。
第一组包含2007年9月至10月采集的303份CSN滤膜样品，该批次样品曾于2008年由DRI采用DRI-2001型号分析仪完成分析。
第二组包含2017年5月至9月采集的4073份CSN样品及622份CSN现场空白样，样品采集后一年内，先后由加州大学戴维斯分校（University of California, Davis, UC Davis）的Sunset分析仪，以及DRI的DRI-2015型号分析仪完成分析。

Sunset及DRI-2015型分析仪的测量数据以质量负载量（微克每平方厘米，μg/cm²）形式报告。Sunset原始数据由加州大学戴维斯分校开发的定制R计算包进行处理。DRI-2015型分析仪的数据由厂商提供的计算程序生成。2007年存档CSN样品的DRI-2001型数据，从美国环境保护署（Environmental Protection Agency, EPA）空气质量系统（Air Quality System, AQS）数据库（https://aqs.epa.gov/aqsweb/documents/data_api.html，最后访问日期：2021年4月28日）下载获取。为与Sunset数据进行直接比对，采用标称采样体积（33立方米，33 m³）及滤膜面积（3.53平方厘米，3.53 cm²），将浓度数据（微克每立方米，μg/m³）转换为质量负载量（微克每平方厘米，μg/cm²）。