AAAR 37th Annual Conference October 14 - October 18, 2019 Oregon Convention Center Portland, Oregon, USA
Abstract View
H2SO4-H2O Binary and H2SO4-H2O-NH3 Ternary Homogeneous and Ion-mediated Nucleation: Lookup Tables and Comparisons with CLOUD Measurements
FANGQUN YU, Alexey Nadykto, Gan Luo, Jason Herb, The State University of New York at Albany
Abstract Number: 910 Working Group: Aerosol Chemistry
Abstract New particle formation is a key source of atmospheric particles which have important implications for air quality and climate. Recently, we have developed a comprehensive kinetically-based H2SO4-H2O-NH3-Ions nucleation model that is based on the thermodynamic data derived from both quantum-chemical calculations and laboratory measurements. The model captures well the absolute values of nucleation rates as well as the dependence of nucleation rates on concentrations of NH3 and H2SO4, ionization rates, temperature, and relative humidity observed in the well-controlled Cosmics Leaving OUtdoor Droplets (CLOUD) measurements. Here we employ this recently developed kinetic nucleation model to generate nucleation rate look-up tables for H2SO4-H2O binary homogenous nucleation (BHN), H2SO4-H2O-NH3 ternary homogeneous nucleation (THN), H2SO4-H2O-Ions binary ion-mediated nucleation (BIMN), and H2SO4-H2O-NH3-Ions ternary ion-mediated nucleation (TIMN). The look-up tables cover a wide range of key parameters that can be found in the atmosphere, and their usage significantly reduces the computational costs of the BHN, THN, BIMN, and TIMN rate calculations, which is critical for multi-dimensional modeling. The look-up tables can also be used by those involved in experiments and field measurements to quickly assess the likeliness of inorganic nucleation involving H2SO4, H2O, NH3, and Ions. The lookup tables have been incorporated into three widely used community CESM-CAM5, GEOS-Chem, and WF-Chem and examples of nucleation rates are presented.