Measuring and modeling the physicochemical properties of organic matter in atmospheric aerosols and their effect on Earth's climate.
Advisor: Mark Z. Jacobson
The hygroscopic growth of atmospheric aerosols has far-reaching effects on atmospheric chemistry, particle pollution health impacts and Earth's climate. The uptake of water by particles affects both their light‐scattering properties (direct effect on climate) and their activation into cloud droplets and precipitation (indirect effect on climate). Both effects account for the largest cause of uncertainty in global warming estimates. The hygroscopic behavior of a particle is governed by its chemical composition. Organic matter often comprises 20-50% of the dry mass of atmospheric aerosols, and can be as high as 90% over biomass burning regions during the burning season. A substantial fraction of these organic compounds are water soluble. This large organic mass content may strongly influence the water uptake properties of atmospheric aerosols. Therefore, a better understanding of organic aerosols is critical to reducing aerosol-related uncertainties on global climate models and improving air quality.
Our work is focused on quantifying and modeling the hygrocospic behavior of different organic solutes commonly found in atmospheric aerosols. We built an apparatus to measure water activity over bulk solutions as a function of temperature and solute concentration. From these measurements, we derive the hygroscopic growth as a function of water activity for particles of different compositions, including pure organic solutes and their mixtures with other compounds. These solutes include an important category of organic matter, secondary organic aerosols (SOA). In order to study their hygroscopic growth, we have designed and built an indoor smog chamber that generates and collects SOA from the photo-oxidation of terpenes in the presence of nitrogen oxides.
Ph.D. in Earth, Energy and Environmental Sciences,
Stanford University, in progress
M.S. in Chemical Engineering, Stanford University, March 2007
B.S. in Chemical Engineering, University of Puerto Rico, December 2003
Curriculum Vitae PDF
Idania R. Zamora
Yang and Yamazaki Environment & Energy Building
473 Via Ortega, Room M05
Stanford, CA 94305-4020
Phone: (650) 725-3025
Fax: (650) 725-3162
Last modified Tuesday, 02-Oct-2012 22:51:56 PDT