Simulating Aerosol Optical Properties With the Aerosol Simulation Program (ASP): Closure Studies Using ARCTAS Data

Type: Presentation

Venue: AGU Fall Meeting 2012

Citation:

Matthew J. Alvarado; Helen L. Macintyre; Huisheng Bian; Mian Chin; Chien Wang (2012) Simulating Aerosol Optical Properties With the Aerosol Simulation Program (ASP): Closure Studies Using ARCTAS Data. AGU Fall Meeting 2012, San Francisco, CA
 

The scattering and absorption of ultraviolet and visible radiation by aerosols can significantly alter actinic fluxes and photolysis rates. Accurate modeling of aerosol optical properties is thus essential to simulating atmospheric chemistry, air quality, and climate. Here we evaluate the aerosol optical property predictions of the Aerosol Simulation Program (ASP) with in situ data on aerosol scattering and absorption gathered during the Arctic Research of the Composition of the Troposphere from Aircraft and Satellites (ARCTAS) campaign. The model simulations are initialized with in situ data on the aerosol size distribution and composition. We perform a set of sensitivity studies (e.g., internal vs. external mixture, core-in-shell versus Maxwell-Garnett, fraction of the organic carbon mass that is light-absorbing “brown carbon,” etc.) to determine the model framework and parameters most consistent with the observations. We compare the ASP results to the aerosol optical property lookup tables in FAST-JX and suggest improvements that will better enable FAST-JX to simulate the impact of aerosols on photolysis rates and atmospheric chemistry.