Aerosol climate

Stier P, Feichter J, Kinne S, Kloster S, Vignati E, Wilson J, Ganzeveld L, Tegen I, Werner M, Balkanski Y, Schulz M, Boucher O, Minikin A, Petzold A (2005) The aerosol-climate model ECHAM5-HAM. Atmos Chem Phys 5 1125-1156 Tanabe S, Tatsukawa R (1983) Vertical transport and residence time of chlorinated hydrocarbons in the open ocean water column. Journal of the Oceanographical Society of Japan 39 53-62 Tiedtke M (1989) A comprehensive mass flux scheme for cumulus parameterization in large scale models. Mon WeaRev 117 1779-1800... 

The climate effects of atmospheric aerosol particles are a matter of continuous interest in the research community. The aerosol-climate effects are divided into two groups The direct effect represents the ability of the particle population to absorb and scatter short-wave radiation - directly affecting the radiation balance. These direct effects depend primarily on the aerosol optical properties and particle number size distribution, as the particle size significantly affects the scattering efficiency of... 

The influence of aerosols on radiative forcing depends on the balance between three essential quantities single-scattering albedo, upscatter fraction, and optical depth—all are sensitive functions of the aerosol chemical composition and size distribution in the 0.1 to 1.0 pm range [1,14]. Aerosol climate forcing, AF, depends on geophysical and aerosol parameters and can be expressed as... 

Ramanathan V., Crutzen P. J., Kiehl J. T., and Rosenfeld D. (2001a) Aerosols, climate, and the hydrological cycle. 

Spatial scales characteristic of various atmospheric chemical phenomena are given in Table 1.1. Many of the phenomena in Table 1.1 overlap for example, there is more or less of a continuum between (1) urban and regional air pollution, (2) the aerosol haze associated with regional air pollution and aerosol-climate interactions, (3) greenhouse gas increases and stratospheric ozone depletion, and (4) tropospheric oxidative capacity and stratospheric ozone depletion. The lifetime of a species is the average time that a molecule of that species resides in the atmosphere before removal (chemical transformation to another species counts as removal). Atmospheric lifetimes vary from less than a second for... 

Harshvardhan (1993) Aerosol-climate interactions, n Aerosol-Cloud-Climate Interactions, edited by P. V. Hobbs. Academic Press, San Diego, pp. 75-95. 

In addition to homogeneous reactions in the stratosphere and troposphere, characteristics, fluid dynamics, thermodynamics, nucleation, deposition processes, organic aerosols, climate effect regarding aerosols are expounded. In particular, efforts are made to explain each process starting from basic principles. 

Rabinowitz, D.L., Barkume, K., Brown, M.E., Roe, H., Schwartz, M., TourteUotte, S., Trujillo, C. Photometric observations constraining the size, shape, and albedo of 2003 EL61, a rapidly rotating, Pluto-sized object in the Kuiper belt. Astrophys. J. 639,1238-1251 (2006) Ramanathan, V, Crutzen, P.J., Kiehl, J.T, Rosenfeld, D. Aerosols, climate, and the hydro-logical cycle. Science 294, 2119-2124 (2001)... 

DMS has been observed in the marine atmosphere since the early 1970s, but it was not until the mid-1980s that there was interest in this gas as being a natural source for sulfate CCN. Sulfate aerosols are, in number terms, the dominant source of CCN. The major role clouds play in the climate system leads to possible climatic implications if changes to DMS production occurred. Furthermore, the dependence of this production on environment conditions means that scope for a feedback process arises this feedback is called the Charlson hypothesis. ... 

It is clear that human action can affect seven of eight of the major gi eenhouse forcings carbon dioxide, methane, nitrous oxide, ozone, CFCs, aerosols, and water vapor. As studies of solar variation have shown, it is also clear that human action is not the only factor involved in determining the impact of these forcings. There is still substantial uncertainty regarding the actual climate impact of the climate forcings. 

Current climate change models have acknowledged weaknesses in their handling of changes in the sun s output, volcanic aerosols, oceanic processes, and land processes that can influence climate change. Some of those uncertainties are large enough, by... 

One such feedback is the influence of clouds and water vapor. As the climate warms, more water vapor enters the atmosphere. But how much And which parts of the atmosphere, high or low And how does the increased humidity affect cloud formation While the relationships among clouds, water vapor, and global climate are complicated in and of themselves, the situation is further complicated by the fact that aerosols exert a poorly understood influence on clouds. 

The condensed phases also are important to the physical processes of the atmosphere however, their role in climate poses an almost entirely open set of scientific questions. The highest sensitivity of physical processes to atmospheric composition lies within the process of cloud nucleation. In turn, the albedo (or reflectivity for solar light) of clouds is sensitive to the number population and properties of CCN (Twomey, 1977). At this time, it appears impossible to predict how much the temperature of the Earth might be expected to increase (or decrease in some places) due to known changes in the concentrations of gases because aerosol and cloud effects cannot yet be predicted. In addition, since secular trends in the appropriate aerosol properties are not monitored very extensively there is no way to know... 

Watson, R. T., Rodhe, H., Oeschger, H. and Siegentha-ler, U. (1990). Greenhouse gases and aerosols. In "Climate Change, the IPCC Scientific Assessment" Q. T. Houghton, G. J. Jenkins and J. J. Ephraums, eds), pp. 1-40. Cambridge University Press, New York. 

Erom R. J. Charlson and Wigley, T. M. E. (1994). "Sulfate Aerosol and Climatic Change," Scientific American, Inc. All rights reserved.)... 

Fig. 17-7 Calculated geographical distribution of the direct climate forcing (W/m ) by one anthropogenic aerosol component, sulfates, from pre-industrial periods to ca. 1990. (Reprinted with permission from IPCC, 1995.)...

Kiehl, J. T. and Briegleb, B. P. (1993). The relative roles of sulfate aerosols and greenhouse gases in climate forcing. Science 260 (16 April), 311-314. 

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