
\def\V{{\bf v}}
\def\ave#1{\overline{#1}}
\def\mave#1{\tilde{#1}}
\def\q{c}

\begin{frame}

\frametitle{Boundary layer in large scale models}

{\footnotesize
Current climate models : horizontal mesh of 20 to 400 km.

Boundary layer processes are subgrid-scale $\implies$
must be "parameterized"

\centerline{\includegraphics[bb=100 40 730 320,clip,width=0.7\textwidth]{gcm1.pdf}}

Parameterizations
\begin{itemize}
\item describe the effect of subgrid-scale processes on large scale state variables
\item through a set of approximate equations based on some internal variables
\item must relate those internal variables to large scale variables (closure) 
\item closely linked to the numerical world.
\end{itemize}
}
\end{frame}
