## 2 Materials and Methods
### Meteorological Factors
Sunshine duration is an important factor in the energy balance of the region under analysis (Table 3). It affects the temperature of the sea's surface, which in turn has an impact on evaporation, the formation of clouds, and atmospheric circulation. Understanding the sunshine distribution in the region is fundamental for an analysis of climate trends and the optimization of maritime operations and the LNG infrastructure, which require adjustment to variable weather conditions. \begin{table}
\begin{tabular}{c c} \hline
**Port** & **Mean Total Yearly Precipitation [mm/m\({}^{2}\)]** \\ \hline Leba & 661.6 \\ Ustka & 666.9 \\ Hel & 598.1 \\ Swinoujšcie & 585.1 \\ Szczecin & 567.0 \\ Kolobrzeg & 697.6 \\ Gdansk & 571.1 \\ \hline \end{tabular}
\end{table} 
Table 2: Mean total yearly precipitation by selected ports, 1991–2020 [35]. Fog is another atmospheric phenomenon that requires detailed examination in an analysis of the hydrological and meteorological conditions in the southern Baltic Sea (Table 4). Caused by condensation of water vapor in the atmospheric boundary layer, it reduces visibility to less than 1 km. The formation of fog is directly related to local meteorological conditions, such as air temperature, humidity, and the speed and direction of wind [57; 58]. \begin{table}
\begin{tabular}{l c c c c c c c} \hline \hline  & \multicolumn{6}{c}{**Mist**} \\ \hline  & Gd\(\ddot{a}\)fsk & Hel & Kolobrzeg & Leba & \(\dot{\text{Swinouj}}\)\(\ddot{\text{c}}\)\(\ddot{\text{c}}\)ie & Szczecin & Ustka \\ January & 20 & 17 & 28 & 21 & 26 & 25 & 19 \\ February & 15 & 14 & 17 & 13 & 19 & 19 & 13 \\ March & 18 & 16 & 18 & 17 & 19 & 19 & 15 \\ April & 10 & 8 & 10 & 9 & 9 & 7 & 8 \\ May & 10 & 9 & 10 & 11 & 12 & 8 & 10 \\ June & 12 & 9 & 16 & 13 & 9 & 7 & 8 \\ July & 8 & 7 & 7 & 11 & 7 & 8 & 7 \\ August & 12 & 3 & 10 & 6 & 8 & 5 & 4 \\ September & 9 & 5 & 12 & 7 & 12 & 11 & 6 \\ October & 17 & 11 & 14 & 13 & 19 & 19 & 10 \\ November & 23 & 18 & 21 & 20 & 24 & 24 & 20 \\ December & 23 & 18 & 21 & 21 & 24 & 22 & 19 \\ Total & 178 & 134 & 182 & 161 & 188 & 173 & 139 \\ \hline \multicolumn{6}{c}{**Fog**} \\ \hline  & Gd\(\ddot{a}\)fsk & Hel & Kolobrzeg & Leba & \(\dot{\text{Swinouj}}\)\(\ddot{\text{c}}\)ie & Szczecin & Ustka \\ January & 3 & 1 & 2 & 2 & 2 & 0 & 1 \\ February & 4 & 1 & 4 & 3 & 2 & 3 & 3 \\ March & 2 & 2 & 4 & 2 & 3 & 2 & 2 \\ April & 4 & 2 & 4 & 7 & 1 & 1 & 3 \\ May & 3 & 1 & 3 & 6 & 3 & 3 & 5 \\ June & 3 & 1 & 7 & 11 & 1 & 1 & 7 \\ July & 3 & 0 & 1 & 9 & 0 & 2 & 2 \\ August & 6 & 0 & 3 & 3 & 0 & 2 & 1 \\ September & 6 & 0 & 2 & 3 & 1 & 3 & 1 \\ October & 5 & 1 & 2 & 3 & 2 & 7 & 1 \\ November & 7 & 2 & 3 & 3 & 3 & 5 & 1 \\ December & 4 & 2 & 4 & 3 & 2 & 2 & 1 \\ Total & 49 & 11 & 38 & 55 & 21 & 31 & 29 \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Number of days with mist and fog by selected ports, 2018–2023 [43]. \begin{table}
\begin{tabular}{l c c c c c c c} \hline \hline  & \multicolumn{1}{c}{**Gd\(\ddot{a}\)fsk**} & \multicolumn{1}{c}{**Hel**} & \multicolumn{1}{c}{**Kolobrzeg**} & \multicolumn{1}{c}{**Leba**} & \(\dot{\text{Swinouj}}\)\(\ddot{\text{c}}\)**\(\ddot{\text{c}}\)ie & \(\dot{\text{Szc}}\)**\(\ddot{\text  
There are several types of fog in the Baltic Sea, especially in the southern part of the region, caused by various atmospheric phenomena [59; 60; 61; 62]:  
* Advection fog--caused by the movement of warm air over a cooler water surface, leading to vapor condensation; the most common type of fog in sea areas, especially in spring and autumn;
* Radiation fog--forms mainly at right and in the early morning when, as a result of the radiation of warmth from the surface of the sea, the atmospheric boundary layer gets cooler;
* Frontal fog--forms with the passing of warm, atmospheric fronts, which lead to strong humidity condensation. Fog considerably affects the safety of maritime transport and operation of the LNG infrastructure. Restricted visibility impedes navigation, increases the risk of collision, and may lead to delays in harbor operations.