Six-moment representation of multiple aerosol populations in a sub-hemispheric chemical transformation model

• Published in: Geophysical research letters Vol. 27; no. 7; pp. 967 - 970
• Main Authors: Wright, D. L., McGraw, R., Benkovitz, C. M., Schwartz, S. E.
• Format: Journal Article
• Language: English
• Published: Washington, DC Blackwell Publishing Ltd 01.04.2000; American Geophysical Union
• Subjects: Earth, ocean, space; Exact sciences and technology; External geophysics; Geophysics. Techniques, methods, instrumentation and models; Transport process; Three dimensional model; Chemical transformation; Geographic distribution; Moment method; Aerosols; Numerical simulation
• ISSN: 0094-8276; 1944-8007
• DOI: 10.1029/1999GL010975

This letter describes the first application of the Quadrature Method of Moments (QMOM) [McGraw, 1997] in a 3‐D chemical transformation and transport model. The QMOM simultaneously tracks an arbitrary (even) number of moments of a particle size distribution directly in space and time without the need for explicitly representing the distribution itself. The host 3‐D model, the Global Chemistry Model driven by Observation‐derived meteorological data (GChM‐O), has been previously described [Benkovitz et al., 1994]. The present implementation evolves the six lowest‐order radial moments for each of several externally‐mixed aerosol populations. From these moments we report modeled geographic distributions of several aerosol properties, including a shortwave radiative forcing obtained using the Multiple Isomomental Distribution Aerosol Surrogate (MIDAS) technique [Wright, 2000]. These results demonstrate the capabilities of these moment‐based techniques to simultaneously represent aerosol nucleation, condensation, coagulation, dry deposition, wet removal, cloud activation, and transport processes in a large scale model, and to yield aerosol optical properties and radiative influence from the modeled aerosol.