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  • Source apportionment resolved by time of day for improved deconvolution of primary source contributions to air pollution
Title: Source apportionment resolved by time of day for improved deconvolution of primary source contributions to air pollution
Abstract. Present methodologies for source apportionment assumefixed source profiles. Since meteorology and human activity patterns changeseasonally and diurnally, application of source apportionment techniques toshorter rather than longer time periods generates more representative massspectra. Here, we present a new method to conduct source apportionmentresolved by time of day using the underlying approach of positive matrixfactorization (PMF). We call this approach “time-of-day PMF” andstatistically demonstrate the improvements in this approach over traditionalPMF. We report on source apportionment conducted on four example timeperiods in two seasons (winter and monsoon seasons of 2017), using organic aerosolmeasurements from an aerosol chemical speciation monitor (ACSM). We deploythe EPA PMF tool with the underlying Multilinear Engine (ME-2) as the PMFsolver. Compared to the traditional seasonal PMF approach, we extract alarger number of factors as well as PMF factors that represent the expectedsources of primary organic aerosol using time-of-day PMF. By capturingdiurnal time series patterns of sources at a low computational cost,time-of-day PMF can utilize large datasets collected using long-termmonitoring and improve the characterization of sources of organic aerosolcompared to traditional PMF approaches that do not resolve by time of day.  more » « less
Award ID(s):
1653625
PAR ID:
10376952
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Atmospheric Measurement Techniques
Volume:
15
Issue:
20
ISSN:
1867-8548
Page Range / eLocation ID:
6051 to 6074
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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