Analysis of Mixing States and Morphology of Individual Particles for Improved Representation in Atmospheric Models
EMSL Project ID
48867
Abstract
Atmospheric aerosols affect the climate directly by absorbing and scattering radiation and indirectly by impacting the properties and lifetimes of clouds. Aerosol processes, such as wet removal, responsible for the “rain out” of aerosol from the atmosphere are poorly represented in climate models. There is evidence that wet removal processes are sensitive to the detailed composition of individual particles. In order to gain a better understanding of the effect of aerosol chemical transformation on removal processes, detailed observations of particle populations at the single particle level are necessary. Tropical locations are of specific interest due to the lack of such detailed climate-related measurements in these regions. The green ocean amazon (GOAmazon) field campaign was set up to study the interaction of biogenic emissions with an urban pollution plume in a tropical environment. As the urban plume mixes with biogenic emissions, the chemical associations (mixing state) within the individual aerosol particles is expected to change the cloud forming properties of the particles. Specifically, as biogenic organic compounds become oxidized, they condense onto pre-existing aerosol. Both the chemical characteristics and amount of organic coatings have been shown to affect the ability of the particle to serve as a cloud particle nucleus. Here it is proposed to use computer controlled scanning electron microscopy coupled with energy dispersive X-ray spectroscopy (CCSEM/EDX) to gain a detailed understanding of the effects the anthropogenic/biogenic interaction on the aging and mixing state of tens of thousands of individual particles sampled during the GOAmazon campaign.
Project Details
Project type
Large-Scale EMSL Research
Start Date
2015-10-01
End Date
2016-09-30
Status
Closed
Released Data Link
Team
Principal Investigator
Co-Investigator(s)
Team Members
Related Publications
Moffet R, R O'Brien, PA Alpert, ST Kelly, DQ Pham, MK Gilles, DA Knopf, and A Laskin. 2016. "Morphology and Mixing of Black Carbon Particles Collected in Central California During the CARES Field Study." Atmospheric Chemistry and Physics 16(22):14515-14525. doi:10.5194/acp-16-14515-2016