## 3 Results
### SOS and POS Trend Analysis (2001-2021)
\begin{table}
\begin{tabular}{c c c c c c c c c c c c} \hline \hline  & \multicolumn{4}{c}{**Winter**} & \multicolumn{4}{c}{**Spring**} \\ \hline
**ID** & **T Mean** & **R Years** & **Sign.** & **R SOS** & **Sign.** & **T Mean** & **R Years** & **Sign.** & **R SOS** & **Sign.** & **R POS** & **Sign.** \\ \hline AUS1 & \(1.12\) & \(0.78\) & **<0.01** & \(-0.51\) & **0.09** & \(13.93\) & \(-0.11\) & \(0.74\) & \(-0.41\) & \(0.19\) & \(-0.22\) & \(0.5\) \\ AUS2 & \(-4.15\) & \(0.72\) & **<0.01** & \(-0.36\) & \(0.16\) & \(5.9\) & \(0\) & \(0.99\) & \(-0.03\) & \(0.91\) & \(-0.52\) & **0.03** \\ BOS & \(3.73\) & \(0.74\) & **<0.01** & \(-0.63\) & **0.01** & \(16.1\) & \(0.62\) & **0.01** & \(-0.61\) & **0.01** & \(-0.64\) & **0.01** \\ BUL & \(-9.07\) & \(0.68\) & **<0.01** & \(-0.28\) & \(0.25\) & \(-0.22\) & \(0.47\) & **0.04** & \(-0.16\) & \(0.51\) & \(0.18\) & \(0.45\) \\ CZE & \(1.73\) & \(0.66\) & **<0.01** & \(-0.55\) & **0.02** & \(13.82\) & \(0.33\) & \(0.18\) & - & - & \(-0.3\) & \(0.23\) \\ DEN & \(2.16\) & \(0.72\) & **<0.01** & \(-0.64\) & **<0.01** & \(11.44\) & \(0.76\) & **<0.01** & \(-0.29\) & \(0.24\) & \(-0.62\) & **<0.01** \\ FRA1 & \(2.33\) & \(0.56\) & **0.01** & \(-0.27\) & \(0.27\) & \(13.79\) & \(0.05\) & \(0.84\) & \(-0.57\) & **0.01** & \(-0.06\) & \(0.82\) \\ FRA2 & \(4\) & \(0.36\) & \(0.13\) & \(-0.67\) & **<0.01** & \(12.93\) & \(-0.24\) & \(0.32\) & \(-0.17\) & \(0.48\) & \(0.09\) & \(0.72\) \\ FRA3 & \(10.82\) & \(0.65\) & **<0.01** & \(-0.08\) & \(0.75\) & \(18.07\) & \(0.11\) & \(0.65\) & \(0.09\) & \(0.71\) & \(-0.49\) & **0.03** \\ GEO & \(0.06\) & \(0.25\) & \(0.43\) & \(0.02\) & \(0.95\) & \(13.22\) & \(-0.01\) & \(0.97\) & \(-0.29\) & \(0.34\) & \(0.15\) & \(0.62\) \\ GER1 & \(1.91\) & \(0.46\) & **0.08** & \(-0.03\) & \(0.91\) & \(12.92\) & \(0.24\) & \(0.39\) & - & - & \(-0.41\) & \(0.13\) \\ GER2 & \(2.77\) & \(0.3\) & \(0.21\) & \(0\) & \(1\) & \(13.15\) & \(0.12\) & \(0.63\) & \(-0.32\) & \(0.18\) & \(0\) & \(0.99\) \\ HUN & \(2.26\) & \(0.61\) & **0.01** & \(-0.31\) & \(0.27\) & \(16.45\) & \(0.36\) & \(0.13\) & - & - & - & \(0.04\) & \(0.87\) \\ ITA1  & \(-0.24\) & - & - & - & 9.46 & - & - & - & - & - & - & - \\ ITA2  & \(-3.83\) & \(0.1\) & \(0.67\) & \(0.02\) & \(0.93\) & \(4.94\) & \(-0.36\) & \(0.13\) & \(-0.04\) & \(0.88\) & \(-0.16\) & \(0.52\) \\ ITA3  & \(-\) & - & - & - & - & - & - & - & - & - & - \\ ITA4  & \(8.17\) & \(0.67\) & \(0.01\) & \(0.32\) & \(0.27\) & \(17.48\) & \(-0.07\) & \(0.82\) & \(-0.35\) & \(0.22\) & \(-0.56\) & **0.04** \\ LAT & \(-3.92\) & \(0.53\) & **0.04** & \(-0.52\) & **0.05** & \(10.8\) & \(0.51\) & **0.05** & \(-0.53\) & **0.04** & \(-0.55\) & **0.03** \\ POL & \(-0.32\) & \(0.53\) & **0.02** & \(-0.32\) & \(0.18\) & \(12.32\) & \(0.23\) & \(0.34\) & \(-0.57\) & **0.01** & \(-0.55\) & **0.02** \\ ROM4  & \(1.88\) & - & - & - & - & \(15.02\) & - & - & - & - & - & - \\ RUSI & \(-3.57\) & \(0.48\) & **0.04** & \(-0.33\) & \(0.17\) & \(14.09\) & \(0.44\) & **0.06** & \(-0.28\) & \(0.25\) & \(-0.74\) & **<0.01** \\ RUSI2  & \(1.24\) & - & - & - & - & \(11.53\) & - & - & - & - & - & - \\ \hline \hline \end{tabular}
\end{table} 
Table 5: Results of the statistical analysis conducted on weather data from 2001 to 2021. _R years_ highlights temperature trends over the 2001–2021 period by reporting the values of the correlation coefficients found by correlating the average winter and spring temperatures with the reference years, while _R SOS_ and _R POS_ report the values found by comparing the extracted SOS and POS with the average winter and spring temperatures of the respective years. For each comparison, the level of significance F is reported (_Sign._). _T mean_ values represent the mean temperatures of the winter and spring seasons, reported to give general information about each site (data not included in the analysis). Figure 5: Changes (days) in POS during the period 2001–2021. SOS advance is highlighted with red circles, whereas delay is highlighted with green circles.