Chapter 10
Calculating Optical Characteristics
of Atmospheric Aerosol
Abstract Calculations of optical characteristics: scattering and absorption
coefficients and phase function of modelled ensembles of aerosol particles are
considered. The description of the practice is given.
10.1 Atmospheric Aerosol
An equilibrium mixture of gas and solid or liquid particles in the atmosphere is
called atmospheric aerosol (sometimes they use plural aerosols for particle
variability). Atmospheric science implies particles itself in the air. Sources of
atmospheric aerosol are extremely varied: dust lifted into the atmosphere by wind
(mineral, silicates), sea-salt crystals remaining after sea water droplets evaporates,
products of chemical reactions in the atmosphere (including photochemical
reactions producing smog), volcanic eruptions, product of fires (soot aerosols)
and anthropogenic (industrial) pollution. According to the definition clouds and
fogs are aerosols too, but usually they are separated to a special class of atmospheric
objects.
Atmospheric aerosol plays an important role in radiative processes in the
atmosphere. It interacts (absorbs and scatters) solar and heat radiation and
determines atmospheric optical properties. This interaction is especially essential
in the shortwave spectral ranges (from UV till near infrared), right where the maximum of the solar flux is situated. There is an important feature of the aerosol – its
strong space and temporal variability: the aerosol content in the air of big cities is twothree orders higher than in the clean air, heavy volcanic eruptions exhaust a lot of
matter to the middle atmosphere and change optical properties of the stratosphere
for months and even years. Thus the stipulated importance of studying and numerical simulating of aerosol optical properties is undoubted.
I. Melnikova et al., Remote Sensing of the Environment and Radiation Transfer,
DOI 10.1007/978-3-642-14899-6_10, # Springer-Verlag Berlin Heidelberg 2012
99
Calculating Optical Characteristics
of Atmospheric Aerosol
Abstract Calculations of optical characteristics: scattering and absorption
coefficients and phase function of modelled ensembles of aerosol particles are
considered. The description of the practice is given.
10.1 Atmospheric Aerosol
An equilibrium mixture of gas and solid or liquid particles in the atmosphere is
called atmospheric aerosol (sometimes they use plural aerosols for particle
variability). Atmospheric science implies particles itself in the air. Sources of
atmospheric aerosol are extremely varied: dust lifted into the atmosphere by wind
(mineral, silicates), sea-salt crystals remaining after sea water droplets evaporates,
products of chemical reactions in the atmosphere (including photochemical
reactions producing smog), volcanic eruptions, product of fires (soot aerosols)
and anthropogenic (industrial) pollution. According to the definition clouds and
fogs are aerosols too, but usually they are separated to a special class of atmospheric
objects.
Atmospheric aerosol plays an important role in radiative processes in the
atmosphere. It interacts (absorbs and scatters) solar and heat radiation and
determines atmospheric optical properties. This interaction is especially essential
in the shortwave spectral ranges (from UV till near infrared), right where the maximum of the solar flux is situated. There is an important feature of the aerosol – its
strong space and temporal variability: the aerosol content in the air of big cities is twothree orders higher than in the clean air, heavy volcanic eruptions exhaust a lot of
matter to the middle atmosphere and change optical properties of the stratosphere
for months and even years. Thus the stipulated importance of studying and numerical simulating of aerosol optical properties is undoubted.
I. Melnikova et al., Remote Sensing of the Environment and Radiation Transfer,
DOI 10.1007/978-3-642-14899-6_10, # Springer-Verlag Berlin Heidelberg 2012
99