Atmospheric oxidation of biogenic hydrocarbons, such as monoterpenes, i estimated to be a significant source of global aerosol. Whereas laboratory studies have established that photochemical oxidation of monoterpenes leads to aerosol formation, there are limited field studies detecting such oxidation products in ambient aerosols. Drawing on prior results of monoterpene product analysis under co...

A modal aerosol module (MAM) has been developed for the Community Atmosphere Model version 5 (CAM5), the atmospheric component of the Community Earth System Model version 1 (CESM1). MAM is capable of simulating the aerosol size distribution and both internal and external mixing between aerosol components, treating numerous complicated aerosol processes and aerosol physical, chemical and optical...

The formation of new aerosol from the gas phase is commonly represented in atmospheric modeling with parameterizations of the steady state nucleation rate. Present parameterizations are based on classical nucleation theory or on nucleation rates calculated with a numerical aerosol model. These parameterizations reproduce aerosol nucleation rates calculated with a numerical aerosol model only im...

Monthly mean aerosol optical depth (AOD) over ocean is compared from a total of 9 aerosol retrievals during a 40 months period. Comparisons of AOD have been made both for the entire period and sub periods. We identify regions where there is large disagreement and good agreement between the aerosol satellite retrievals. Significant differences in AOD have been identified in most of the oceanic r...

[1] This paper provides numerics for cloud and precipitation development from multiple aerosol size distributions and examines the effect of clouds and precipitation on aerosol removal. Numerical techniques are given for (1) simultaneous liquid and ice growth onto multiple aerosol size distributions, (2) diffusiophoretic, thermophoretic, gravitational, etc., coagulation among liquid, ice, and g...

T. H. Cheng, X. F. Gu, , and T.Yu 1 State Key Laboratory of Remote Sensing Science, Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University, Beijing, China 2 Demonstration Center for Spaceborne Remote Sensing, Chinese National Space Administration, Beijing, China E-mail: [email protected] Abstract: Aerosol particles in the atm...

The effect of the aerosol phase (solid versus aqueous) on the heterogeneous OH oxidation of succinic acid (C4H6O4) is investigated using an aerosol flow tube reactor. The molecular and elemental transformation of the aerosol is quantified using Direct Analysis in Real Time (DART), a soft atmospheric pressure ionization source, coupled to a high-resolution mass spectrometer. The aerosol phase, c...

We investigate formation of sulfate aerosol in the marine troposphere from neutral and charged nucleation of H2SO4 and H2O. A box model of neutral and charged aerosol processes is run on a grid covering the oceans. Input data are taken from a model of galactic cosmic rays in the atmosphere, and from global chemistry and transport models. We find a weak aerosol production over the tropical ocean...

In order to determine the wavelength dependence of fine (<1 micron) atmospheric aerosol absorption in the Mexico City area, the absorption Ångstrom exponents (AAEs) were calculated from hourly averages of aerosol absorption measured at seven wavelengths (370, 450, 520, 590, 660, 880, and 950 nm) with an aethalometer during two field campaigns, the Mexico City Metropolitan Area study in April 20...

The Gridpoint Statistical Interpolation threedimensional variational data assimilation (DA) system coupled with the Weather Research and Forecasting/Chemistry (WRF/Chem) model was utilized to improve aerosol forecasts and study aerosol direct and semi-direct radiative feedbacks during a US wild fire event. Assimilation of MODIS total 550 nm aerosol optical depth (AOD) retrievals clearly improve...