Atmospheric systems

Figure 1 Proposed NHj cycles in the soil-vegetation-atmosphere system. (Taken from Sutton et...

Using Wien s displacement law, determine the mean effective temperature of the earth-atmosphere system if the resulting longwave radiation peaks at 11 /rm. Contrast the magnitude of the radiant flux at 11 pm with that at 50 pm. 

Figure 2. Within the Earth-atmosphere system numerous feedback loops govern climate. (Reproduced with permission from ref. 31. Copyright 1974 American Association for the Advancement of Science.)...

An important class of cycles with non-linear behavior is represented by situations when coupling occurs between cycles of different elements. The behavior of coupled systems of this type has been studied in detail by Prigogine (1967) and others. In these systems, multiple equilibria are sometimes possible and oscillatory behavior can occur. There have been suggestions that atmospheric systems of chemical species, coupled by chemical reactions, could exhibit multiple equilibria under realistic ranges of concentration (Fox et ai, 1982 White, 1984). However, no such situations have been confirmed by measurements. 

Fig. 18-6 Characteristic air-mass trajectory and corresponding per mil isotopic composition of precipitation, along a transect from the subtropics to a polar ice sheet. This is a highly schematic view of the true atmospheric system.

Riederer, M.(1990) Estimating partitioning and transport of organic chemicals in the foliage/atmosphere system Discussion of a fugacity-based model. Environ. Sci. Technol. 24, 829-837. 

D Klockow, P Jacob. Chemistry of Multiphase Atmospheric Systems Berlin Springer, 1986, pp 117-130. 

For the following we assume that the atmospheric variations in C02 and in its carbon isotopic composition are entirely due to atmospheric system disturbances, such as the input of 14C-free C02 from fossil C02 production, and deviations from the average rate of 14C production by cosmic radiation. The system dynamics, i.e., the exchange coefficients and the eddy diffusivity are kept constant. We approximate the fossil C02 input p(t) by... 

The ocean-atmosphere system contains 35 x 10i5kgC, only 2 percent of which resides in the atmosphere (Berner and Berner, 1987). 

Figure 7.16 Medium-term response of the model described in Figure 7.15 to a sudden increase by 2 percent of the total amount of oxidized carbon in the ocean-atmosphere system. Ca (top) and Z(C02) (bottom) in the ocean.

The photodissociation of S02 into SO and O atoms is markedly different from the photodissociation of N02. The bond to be broken in the sulfur compound requires about 560kJ/mol. Thus, wavelengths greater than 2180 A do not have sufficient energy to initiate dissociation. This fact is significant in that only solar radiation greater than 2900 A reaches the lower atmosphere. If a photochemical effect is to occur in the S02-02 atmospheric system, it must be that the radiation electronically excites the S02 molecule but does not dissociate it. 

Muramatsu, Y., Yoshida, S., and Barmai, T., 1995, Tracer experiments on the behaviour of radioiodine in the soil-plant-atmosphere system", J. Radioanal. Nucl. Chem. - Articles 194 (2), 303-310. 

A 250 kilowatt atmospheric system is planned for a Toronto, Ontario, Canada site. The system will be operated by Ontario Power Technologies (formerly Ontario Hydro). The unit will supply 145 kilowatts of heat to the site heating system. Electric efficiency is expected to be about 47% (LHV). Operation of the combined heat and power system is expected in late 2001. 

Finally, through legislative and administrative action, health-protective and cost-effective risk-management decisions can be made, and regulatory actions implemented, that directly affect the starting point of our atmospheric system, that is, the primary emissions and their sources. 

To place the remainder of this book on atmospheric chemistry in perspective, the various components of our atmospheric system are treated briefly next. 

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