Role of Iodine-Assisted Aerosol Particle Formation in Antarctica

Environmental Science & Technology, Journal Year: 2024, Volume and Issue: 58(17), P. 7314 - 7324

Published: April 16, 2024

New particle formation via the ion-mediated sulfuric acid and ammonia molecular clustering mechanism remains most widely observed experimentally verified pathway. Recent laboratory level observations indicate iodine-driven nucleation as a potentially important source of new particles, especially in coastal areas. In this study, we assess role iodine species using best available thermochemistry data coupled to detailed 1-d column model which is run along air mass trajectories over Southern Ocean coast Antarctica. masses traversing open ocean, SA-NH

Language: Английский

Measurement report: Insights into the chemical composition and origin of molecular clusters and potential precursor molecules present in the free troposphere over the southern Indian Ocean: observations from the Maïdo Observatory (2150 m a.s.l., Réunion)

Atmospheric chemistry and physics, Journal Year: 2024, Volume and Issue: 24(6), P. 3785 - 3812

Published: March 27, 2024

Abstract. New particle formation (NPF) in the free troposphere (FT) is thought to be a significant source of particles over oceans. The entrainment initially formed marine FT further suspected major contributor cloud condensation nuclei (CCN) number concentrations boundary layer (BL). Yet, little known about process and, more broadly, composition FT, which remains poorly explored due access difficulties. Here we report measurements performed April 2018 at Maïdo Observatory with nitrate-based chemical ionization atmospheric pressure interface time-of-flight mass spectrometer, have allowed first molecular-level characterization remote composition. A molecules and clusters were identified classified into nine groups according their composition; among species, containing methanesulfonic acid (MSA) C2 amines show signals that are on average significantly higher when site under conditions representative (compared BL). correlation analysis revealed apparent connections between compounds several variables concurrently measured (under conditions) or related air history, suggesting oxalic acid, malonic observed could terrestrial origin, with, addition, possible for amines, while iodic sulfur maleic dominant origin. Identification was based standard deviation wind direction; this parameter, can easily derived from continuous site, shown part study relevant tracer compared predictions Meso-NH model. Similar other high-altitude sites, mainly encountered night Maïdo; therefore, link NPF not established, research needed assess precursors nanoparticle FT.

Language: Английский

Atmospheric Bases-Enhanced Iodic Acid Nucleation: Altitude-Dependent Characteristics and Molecular Mechanisms

Environmental Science & Technology, Journal Year: 2024, Volume and Issue: unknown

Published: Sept. 9, 2024

Iodic acid (IA), the key driver of marine aerosols, is widely detected within gas and particle phases in boundary layer (MBL) even free troposphere (FT). Although atmospheric bases like dimethylamine (DMA) ammonia (NH

Language: Английский