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the fluctuations. A general systems theory (Selvam
1990
) visualizes each large eddy
as the envelope (average) of enclosed smaller scale eddies, thereby generating the
eddy continuum, a concept analogous to the kinetic theory of gases in classical sta-
tistical physics. It is shown that the ordered growth of atmospheric eddy continuum
in dynamical equilibrium is associated with maximum entropy production.
Two important model predictions of the general systems theory for turbulent
atmospheric flows and their applications are given in the following:
• The probability distributions of amplitude and variance (square of amplitude) of
fractal fluctuations are quantified by the same universal inverse power law in-
corporating the golden mean. Universal inverse power law for power spectra of
fractal fluctuations rules out linear secular trends in meteorological parameters.
Global warming-related climate change, if any, will be manifested as intensifi-
cation of fluctuations of all scales manifested immediately in high-frequency
fluctuations (Selvam et al.
1992
; Selvam
2011
)
• The mass or radius (size) distribution for homogeneous suspended atmospheric
particulates is expressed as a universal scale-independent function of the golden
mean τ, the total number concentration, and the mean volume radius. Model-pre-
dicted aerosol size spectrum is in agreement (within two standard deviations on
either side of the mean) with total averaged radius size spectra for the VOCALS
2008 PCASP-B data sets. SAFARI 2000 aerosol size distributions reported by
Haywood et al. (
2003
) also show similar shape for the distributions. Specifica-
tion of cloud droplet size distributions is essential for the calculation of radia-
tion transfer in clouds and cloud-climate interactions, and for remote sensing of
cloud properties. The general systems theory model for aerosol size distribution
is scale-free and is derived directly from atmospheric eddy dynamical concepts.
At present empirical models such as the log normal distribution with arbitrary
constants for the size distribution of atmospheric suspended particulates is used
for quantitative estimation of the earth-atmosphere radiation budget related to
climate warming/cooling trends (Sect. 2.1). The universal aerosol size spectrum
presented in this chapter may be computed for any location with two measured
parameters, namely, the mean volume radius and the total number concentration
and may be incorporated in climate models for computation of radiation budget
of earth-atmosphere system.
References
Haywood J, Francis P, Dubovik O, Glew M, Holben B (2003) Comparison of aerosol size distribu-
tions, radiative properties, and optical depths determined by aircraft observations. J Geophys
Res 108(D13) 8471:SAF 7-1 to 12
Husar RB (2005) The emergence of the bimodal distribution concept. In: Sem GJ, Boulaud D,
Brimblecombe P, Ensor ES, Gentry JW, Marijnissen JCM, Preining O (eds) History reviews of
aerosol science. American Association for Aerosol Research, Mt. Laurel
IPCC Fourth Assessment Report (AR4) (2007) Climate change 2007. The physical science basis.
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