AAAR 35th Annual Conference October 17 - October 21, 2016 Oregon Convention Center Portland, Oregon, USA
Abstract View
Reduced Representation of the Aerosol Mixing State through the Quadrature Method of Moments
LAURA FIERCE, Robert McGraw, Brookhaven National Laboratory
Abstract Number: 618 Working Group: Aerosol Physics
Abstract Sparse representations of atmospheric aerosols are needed for efficient regional- and global-scale chemical transport models. Here we demonstrate a new framework for simulation complex aerosol distributions, based on the quadrature method of moments. We show that key features of aerosol populations are captured using quadrature approximations of multivariate moments. Each quadrature consists of a collection of abscissas, or representative particles, and associated weights. Distributions with respect to key aerosol quantities, such as the critical supersaturation for CCN activation or optical cross sections, can be approximately reconstructed using constrained maximum entropy distributions. Unlike the commonly used sparse representations, such as modal and sectional schemes, the maximum-entropy moment-based approach is not constrained to pre-determined size bins or assumed distribution shapes. CCN activity and optical properties from the sparse aerosol simulations are benchmarked against the particle-resolved model PartMC-MOSAIC. This study is a first step toward a new aerosol simulation scheme for large-scale simulations that will track multivariate aerosol distributions with sufficient computational efficiency for large-scale simulations.