Aerosol effect

Hofmann, D. J., and S. J. Oltmans, Anomalous Antarctic Ozone during 1992 Evidence for Pinatubo Volcanic Aerosol Effects, J. Geophys. Res., 98, 18555-18561 (1993). 

Gaffney, J. S., and N. A. Marley, Uncertainties of Aerosol Effects in Global Climate Models, Atmos. Environ, 32, 2873-2874 (1998). 

Rasool, S. I., and S. H. Schneider, Atmospheric Carbon Dioxide and Aerosols Effects of Large Increases on Global Climate, Science, 173, 138-141 (1971). 

Charlock, T. P., and W. D. Sellers, 1980. Aerosol effects on climate calculations with time-dependent and steady-state radiative-convective models, J. Atmos. Sci., 37, 1327-1341. 

Figure 1. Stratospheric aerosol effective radii derived from a variety of measurements and techniques [1].

Arola A, Lindfors A, Natunen A, Lehtinen KEJ (2007) A case study on biomass burning aerosols effects on aerosol optical properties and surface radiation levels. Atmos Chem Phys... 

Lohmann, U., and Feichter, J. (2005). Global indirect aerosol effects A review. Atmos. Chem. Phys. 5,715-737. 

Johnson B.T. Shine K.P. and Forster P.M. (2004). The semi-direct aerosol effect Impact of absorbing aerosols on marine stratocumulus. Quart. J. Roy. Meteorol. Soc., 130, Part B, No. 599, 1407-1422. 

Peng Y. and Lohmann U. (2003). Sensitivity study of the spectral dispersion of the cloud droplet size distribution on the indirect aerosol effect. Geophys. Res. Lett., 30(10), 14/1-14/4. 

For the realization of all aerosol forcing mechanisms in integrated systems it is necessary to improve not only ACTMs, but also NWP/MetMs. The boundary layer structure and processes, including radiation transfer, cloud development and precipitation must be improved. Convection and condensation schemes need to be adjusted to take the aerosol-cloud microphysical interactions into account, and the radiation scheme needs to be modified to include the aerosol effects. 

Harshvardan and Cess R.D., Stratospheric aerosols Effect upon atmospheric temperature and global climate. Tellus , 28, 1-10 (1976). 

Apparent changes in atmospheric fine particle concentrations within the 30° to 60° latitude zone in the northern hemisphere have been pointed out by McCormick and Ludwig (14) and by Flowers et ah (15), based on turbidity measurements made in the United States and Europe. The absence of detectable turbidity changes over a period of 15 years in the southern hemisphere is shown by data presented by Fischer (16). These two observations confirm our earlier remarks relative to the separating of the northern and southern hemispheres and that aerosol effects are noticed most in the mid-latitudes of the northern hemisphere. 

The 3/2-order coefficient k drops from 0.77 to 0.24 Torr min as [NH3] increases from 23.3 to 128 Torr. At higher NH3 pressures, k increases with [NH3]. fc at the two highest NH3 pressures may increase as a result of the sizeable effect of the aerosol attenuation at high [NH3] / [O3]o and as a result of diffusion effects. The aerosol effect was so important in the packed cell (because of the larger rate coefficients) that only one reliable value for fc could be obtained, and its value of 4.85 Torr" / min was larger than in the unpacked cell for similar [NH3]/[03]o ratios. 

Breon E. M., Tanre D., and Generoso S. (2002) Aerosol effect on cloud droplet size monitored from satellite. Science 295, 834-838. 

Lohmann U. and Feichter J. (2001) Can the direct and semi-direct aerosol effect compete with the indirect effect on a global scale Geophys. Res. Lett. 28, 159—161. 

Figure 2 illustrates the kinds of particles made in this study. Here, polystyrene nanoparticles (170-nm diameter) were prepared in an ethanol cosolvent and spray-dried to produce large thin-walled particles with a wall thickness of approximately 400 nm, or 3 layers of nanoparticles. The study showed that such particles aerosolize effectively from a small inhaler and redisperse into nanoparticles once in solution. Nanoparticle aggregates were made with a variety of different materials and through many different spraydrying conditions, suggesting that these large porous nanoparticle systems are robust and functional as aerosols. 

Ipratropium bromide (Sch 1000, continues to be of clinical Interest. The compound has been shown to be superior to fenoterol at doses of 40 p,g as an aerosol. Effectiveness is diminished at higher... 

---