Recent Progress on Atmospheric Science and Chemistry mEasurement NeTwork (ASCENT): Advanced, Ground-based Aerosol Measurement Network Across the U.S.
NGA LEE NG, Roya Bahreini, Ann M. Dillner, Armistead G. Russell, Richard Flagan, James Flynn, Drew Gentner, Robert Griffin, Lelia Hawkins, Jose-Luis Jimenez, Jingqiu Mao, Shane Murphy, Albert Presto, Sean Raffuse, Allen Robinson, John Seinfeld, Jason Surratt, Joel A. Thornton, Georgia Institute of Technology
Abstract Number: 597
Working Group: Aerosol Processes and Properties in Changing Environments in the Anthropocene
Abstract
The Atmospheric Science and Chemistry mEasurement NeTwork (ASCENT) is a new comprehensive, high time-resolution, long-term monitoring network in the U.S. for characterization of aerosol chemical composition and physical properties. ASCENT consists of a network of 12 advanced aerosol measurement sites across the country, leveraging existing monitoring locations and facilities. Each site is equipped with a suite of advanced aerosol instrumentation, including an Aerosol Chemical Speciation Monitor (ACSM, non-refractory aerosols, PM2.5), an Xact (trace metals, PM2.5), an Aethalometer (aerosol light absorption, black and brown carbon, PM2.5), and a Scanning Mobility Particle Sizer (SMPS, aerosol number size distribution and concentration, PM1). All ASCENT sites were operational and sampling as of May 2024. We will present an overview of intercomparisons of ASCENT instrument measurements across different sites, including comparisons with collocated PM2.5 data from other monitoring networks. Analysis of SMPS and chemically-speciated PM2.5 measurements facilitates evaluation of the fraction of PM2.5 mass concentration that is in PM1 in urban, rural, and remote locations. While organic aerosols dominate PM2.5, source apportionment analysis at select sites reveal diversity in organic aerosol composition and sources, with differing impacts from biogenic emissions, anthropogenic activities, and widespread influence of biomass burning emissions. Updates on the development of the data infrastructure will also be provided, including accessibility to different data levels such as real time raw data, near real time data with automated quality control, and annual validated data. The high time-resolution, speciated aerosol measurements at ASCENT sites have provided new insights into the characteristics of aerosols in diverse geographical regions and facilitated collaborative studies across academia, industry, and government. We welcome new collaborative opportunities leveraging the ASCENT infrastructure to advance our understanding of aerosol sources and properties and their impacts on air quality and health.