Environmental Science Division (EVS)a Division of Argonne National Laboratory

Improving the Representation of Atmospheric Aerosols in Large-scale Models through Particle-based Modeling

Tuesday, August 22, 2017

Laura Fierce
NOAA Climate & Global Change Postdoctoral Fellow
Environmental and Climate Sciences
Brookhaven National Laboratory
Tuesday, August 22, 2017
2:00 P.M. to 3:00 P.M.
Argonne National Laboratory
TCS Building 240
Room 4301

Aerosol radiative properties depend on the size and chemical composition of individual particles, but particle-level characteristics are not fully resolved in global-scale models. In my talk, I will describe two different particle-based methods for advancing aerosol representations in large-scale models.

In the first part of my talk, I will describe the application of a particle-resolved model, which is computationally too expensive for large-scale simulation, for benchmarking reduced aerosol representations and for parameterizing unresolved aerosol properties. I will demonstrate that aerosol absorption is overestimated if diversity in particle composition is neglected, but also show that the effects of composition diversity can be approximately represented by a parametric relationship derived from a series of particle-resolved simulations.

In the second part of my talk, I will introduce a new sparse-particle model based on the quadrature method of moments, which is designed for use in large-scale atmospheric models. I will demonstrate that cloud condensation nuclei activity of particle-resolved populations, which are comprised of 10,000 to 1,000,000 Monte Carlo particles, are accurately represented by an optimized set of only eight sparse particles.

This study is a first step toward a new aerosol simulation scheme that will track multivariate aerosol distributions with sufficient computational efficiency for reliable aerosol simulation in global-scale models.

Laura Fierce
Laura Fierce [Source: Brookhaven National Laboratory]
portrait of Yan Feng