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\begin{table}[ht]
    \centering
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    \begin{tabular}{lcccccc}
        \hline
        \multicolumn{7}{l
        }{\textbf{ Bioclimatic indices with temperature correction}} \\
        \hline
        \textbf{Variable} & \textbf{PC1} & \textbf{PC2} & \textbf{PC3} & \textbf{PC4} & \textbf{PC5} & \textbf{PC6} \\
        Huglin index        &  0.54 &  0.19 &  0.06 &  0.08 &  0.17 & -0.79 \\
        Flavescence dorée   &  0.49 &  0.40 &  0.11 & -0.07 &  0.54 &  0.55 \\
        Extreme heat days   &  0.50 & -0.14 &  0.17 & -0.58 & -0.59 &  0.13 \\
        Frost days          & -0.15 &  0.05 &  0.96 &  0.22 & -0.08 &  0.00 \\
        Downy mildew        & -0.44 &  0.32 &  0.11 & -0.75 &  0.28 & -0.23 \\
        Powdery mildew      & -0.10 &  0.83 & -0.15 &  0.19 & -0.50 &  0.03 \\
        \hline
        \textit{Weight}     &  0.53 &  0.22 &  0.16 &  0.07 &  0.01 &  0.00 \\ ~ \\
        \hline
        \multicolumn{7}{l}{\textbf{ Bioclimatic indices without temperature correction}} \\
        \hline
        Huglin index        & 0.55 & 0.18 &  0.08 &  0.07 & -0.20 & -0.79 \\
        Flavescence dorée   & 0.50 & 0.35 &  0.17 & -0.08 & -0.53 &  0.56 \\
        Extreme heat days   & 0.50 & -0.18 &  0.08 & -0.59 &  0.59 &  0.11 \\
        Frost days          & -0.10 & -0.18 &  0.96 &  0.15 &  0.05 & -0.02 \\
        Downy mildew        & -0.43 & 0.32 &  0.14 & -0.75 & -0.27 & -0.21 \\
        Powdery mildew      & -0.07 & 0.83 &  0.08 &  0.21 &  0.51 &  0.03 \\
        \hline
        \textit{Weight}     &  0.52 &  0.23 &  0.16 &  0.07 &  0.01 &  0.00 \\ ~ \\
        \hline
        \multicolumn{7}{l}{\textbf{ Physical parameters}} \\
        \hline
        Daily mean temperature         & 0.51 &  0.27 &  0.04 &  0.01 & -0.81 & \\
        Daily minimum temperature      & 0.48 &  0.43 & -0.04 &  0.62 &  0.45 & \\
        Daily maximum temperature      & 0.52 &  0.14 &  0.10 & -0.75 &  0.37 & \\
        Precipitation                  & -0.35 &  0.54 &  0.76 & -0.04 & -0.00 & \\
        Relative humidity              & -0.34 &  0.66 & -0.64 & -0.21 & -0.02 & \\
        \hline
        \textit{Weight}     &  0.71 &  0.17 &  0.11 &  0.01 &  0.00 &       \\
        %\hline
    \end{tabular}
    \caption{Principal Components (PC) and explained variance for three variable sets: bioclimatic indices with and without temperature corrections respectively, and raw physical parameters with temperature corrections}
    \label{tab:combined_pca_summary}
\end{table}

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