Heterogeneous nucleation of ice on anthropogenic organic particles collected in Mexico City

Journal Article · Sun Jun 20 04:00:00 EDT 2010 · GEOPHYSICAL RESEARCH LETTERS

DOI:https://doi.org/10.1029/2010GL043362· OSTI ID:1004596

Knopf, D A; Wang, B; Laskin, A; Moffet, R C; Gilles, M K

This study reports on heterogeneous ice nucleation activity of predominantly organic (or coated with organic material) anthropogenic particles sampled within and around the polluted environment of Mexico City. The onset of heterogeneous ice nucleation was observed as a function of particle temperature (Tp), relative humidity (RH), nucleation mode, and particle chemical composition which is influenced by photochemical atmospheric aging. Particle analyses included computer controlled scanning electron microscopy with energy dispersive analysis of X-rays (CCSEM/EDX) and scanning transmission X-ray microscopy with near edge X-ray absorption fine structure spectroscopy (STXM/NEXAFS). In contrast to most laboratory studies employing proxies of organic aerosol, we show that anthropogenic organic particles collected in Mexico City can potentially induce ice nucleation at experimental conditions relevant to cirrus formation. The results suggest a new precedent for the potential impact of organic particles on ice cloud formation and climate.

• Research Organization: Ernest Orlando Lawrence Berkeley National Laboratory, Berkeley, CA (US)
• Sponsoring Organization: Chemical Sciences Division
• DOE Contract Number: AC02-05CH11231
• OSTI ID: 1004596
• Report Number(s): LBNL-4221E
• Journal Information: GEOPHYSICAL RESEARCH LETTERS, Journal Name: GEOPHYSICAL RESEARCH LETTERS Journal Issue: 11 Vol. 37; ISSN 0094-8276
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
Aerosol
ice nucleation
scanning transmission x-ray microscopy