Pollution mask for the continuous corrected particle number concentration data in 1 min time resolution measured in the Swiss aerosol container using a whole air inlet during MOSAiC 2019/2020

This dataset contains particle number concentrations and a pollution flag in 1 min time resolution. It is derived by the pollution detection algorithm (PDA, doi:10.5281/zenodo.5761101) based on the corrected particle number concentration data of the CPC3776 measured during the year-long MOSAiC expedition from October 2019 to September 2020. With pollution, we refer to emission from the exhaust of the ship stack, snow groomers, diesel generators, ship vents, helicopters and other (primary pollution, not circulated, nor transported). Pollution hence reflects locally emitted particles and trace gases, which are not representative of the central Arctic ambient concentrations. The PDA identifies and flags periods of polluted data in the particle number concentration dataset five steps. The first and most important step identifies polluted periods based on the gradient (time-derivative) of a concentration over time. If this gradient exceeds a given threshold, data are flagged as polluted. Further pollution identification steps are a simple concentration threshold filter, a neighboring points filter (optional), a median and a sparse data filter (optional). The detailed methodology of the derivation of the pollution flag is described in Beck et al. (2022).

本数据集包含时间分辨率为1分钟的颗粒物数浓度数据与污染标识。该数据集基于2019年10月至2020年9月为期一年的MOSAiC科考行动期间，由CPC3776型仪器测得的经校正的颗粒物数浓度数据，通过污染检测算法（Pollution Detection Algorithm，简称PDA，doi:10.5281/zenodo.5761101）生成。本数据集所定义的污染，特指船舶烟囱、雪地整地机、柴油发电机、船舶通风口、直升机等排放源产生的一次污染物（未经过循环扩散或长距离输送）。此类污染反映的是局地排放的颗粒物与痕量气体，无法代表北极中部的环境本底浓度。该污染检测算法通过五步完成颗粒物数浓度数据中的污染时段识别与标识：第一步亦是核心步骤，基于浓度随时间的变化梯度（时间导数）识别污染时段，若该梯度超出设定阈值，则将对应数据标记为受污染状态；其余四步依次为简易浓度阈值过滤、邻点过滤（可选）、中值过滤以及稀疏数据过滤（可选）。污染标识生成的详细方法学内容详见Beck等人（2022）的研究成果。

搜集汇总

背景与挑战

背景概述

该数据集提供了2019年10月至2020年9月MOSAiC北极考察期间，基于每分钟时间分辨率的校正颗粒数浓度数据生成的污染掩码，用于标识由本地污染源（如船舶排放）引起的污染时段。数据集包含颗粒数浓度和污染标志（0表示未污染，1表示污染），通过污染检测算法（PDA）自动生成，旨在帮助研究人员过滤非环境背景的污染数据，适用于北极气溶胶研究。