\subsection{Problem definition} 
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After it has been thoroughly discussed, 
that the physical greenhouse effect 
is essentially the explanation, 
why air temperatures in a closed glass house 
or in a closed car are higher than outside, 
one should have a closer look at the 
fictitious atmospheric greenhouse effects.
 
Meanwhile there are many different phenomena 
and different explanations for these effects,
so it is justified to pluralize here.

Depending on the particular school
and the degree of popularization,
the assumption that the atmosphere is transparent
for visible light but opaque for infrared
radiation is supposed to lead to
%
\begin{itemize}
\item a warming of the Earth's surface
      \textit{and/or}
\item a warming of the lower atmosphere
      \textit{and/or}
\item a warming of a certain layer of the atmosphere
      \textit{and/or}
\item a slow-down of the natural cooling
      of the Earth's surface
\end{itemize}
%
and so forth.

Unfortunately, there is no source
in the literature, where the greenhouse effect
is introduced in harmony with the scientific 
standards of theoretical physics.
As already emphasized,
the \lq\lq supplement\rq\rq\ to Kittel's
book on thermal physics\TschSpace%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\cite{Kittel2000} 
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
only refers to the IPCC assessments\TschSpace%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\cite{IPCC1990,IPCC1992}. 
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
Prominent global climatologists
(as well as \lq\lq climate sceptics\rq\rq) often
present their ideas in handbooks,
encyclopedias, and in secondary 
and tertiary literature.
% 
