Chapter 1
Radiation in the Earth Atmosphere
Abstract The first chapter contains general information about interaction of solar
radiation with the atmosphere, elements of the radiative transfer theory, and base
information about the scattering theory, which is necessary for understanding
practical works. The basic notations of solar radiation characteristics and atmospheric optical parameters together with corresponding equations are presented.
1.1 Characteristics of the Radiation Field in the Atmosphere
In accordance with the contemporary conceptions, light (radiation) is an electromagnetic wave showing the quantum properties. Thus, strictly speaking, the processes of light propagation in the atmosphere should be described within the ranges
of electrodynamics and quantum mechanics. Nevertheless, it is suitable to abstract
from the electromagnetic nature of light to solve the number of problems (including
the problems described in this book) and to consider radiation as an energy flux.
Light characteristics governed by energy are called the radiative characteristics.
This approach is usual for optics because the frequency of the electromagnetic
waves within the optical ranges is huge and the receiver registers only energy,
received during many wave periods (not a simultaneous value of the electromagnetic intensity).
The following main types of radiation (and their energy) are distinguished in solar
radiation transferring throughout the atmosphere: direct radiation (radiation coming
to the point directly from the Sun); diffused solar radiation (solar radiation scattering
in the atmosphere); reflected solar radiation from surface; self-atmospheric radiation
(heat atmospheric radiation) and self-surface radiation (heat radiation). The total
combination of these radiations creates the radiation field in the Earth atmosphere,
which is characterized with energy of radiation coming from different directions
within different spectral ranges. As it is seen from above, it is possible to divide all
radiation to the solar and self (heat) radiation. The maximum of the solar radiation is
I. Melnikova et al., Remote Sensing of the Environment and Radiation Transfer,
DOI 10.1007/978-3-642-14899-6_1, # Springer-Verlag Berlin Heidelberg 2012
1
Radiation in the Earth Atmosphere
Abstract The first chapter contains general information about interaction of solar
radiation with the atmosphere, elements of the radiative transfer theory, and base
information about the scattering theory, which is necessary for understanding
practical works. The basic notations of solar radiation characteristics and atmospheric optical parameters together with corresponding equations are presented.
1.1 Characteristics of the Radiation Field in the Atmosphere
In accordance with the contemporary conceptions, light (radiation) is an electromagnetic wave showing the quantum properties. Thus, strictly speaking, the processes of light propagation in the atmosphere should be described within the ranges
of electrodynamics and quantum mechanics. Nevertheless, it is suitable to abstract
from the electromagnetic nature of light to solve the number of problems (including
the problems described in this book) and to consider radiation as an energy flux.
Light characteristics governed by energy are called the radiative characteristics.
This approach is usual for optics because the frequency of the electromagnetic
waves within the optical ranges is huge and the receiver registers only energy,
received during many wave periods (not a simultaneous value of the electromagnetic intensity).
The following main types of radiation (and their energy) are distinguished in solar
radiation transferring throughout the atmosphere: direct radiation (radiation coming
to the point directly from the Sun); diffused solar radiation (solar radiation scattering
in the atmosphere); reflected solar radiation from surface; self-atmospheric radiation
(heat atmospheric radiation) and self-surface radiation (heat radiation). The total
combination of these radiations creates the radiation field in the Earth atmosphere,
which is characterized with energy of radiation coming from different directions
within different spectral ranges. As it is seen from above, it is possible to divide all
radiation to the solar and self (heat) radiation. The maximum of the solar radiation is
I. Melnikova et al., Remote Sensing of the Environment and Radiation Transfer,
DOI 10.1007/978-3-642-14899-6_1, # Springer-Verlag Berlin Heidelberg 2012
1