\begin{table}%t1
\caption{\label{temp}Mean of temperature values along the mottles.}
%\centering
\par
\small \begin{tabular}{cccc}
\hline \hline
 & \multicolumn{3}{c}{Temperature}\\
 & \multicolumn{3}{c}{($10^{4}$~K)}\\
 & \multicolumn{3}{c}{($\pm$2)}\\
 \hline
Structure & ET & CP & WF \\
\hline
Mottle ${a}$ &  2.1 &  2.8 & 11.3* \\
Mottle ${b}$ &  2.1 &  1.9 &  3.1  \\
Mottle ${c}$ &  3.6 &  2.8 & 16.2* \\
Mottle ${d}$ &  2.8 &  6.8 &  2.0  \\
\hline
\end{tabular}
\end{table}