## 2 Materials and Methods
### Meteorological Factors
\begin{table}
\begin{tabular}{l l l l l l l l} \hline  & **Gd\(\ddot{\text{a}}\)\(\ddot{\text{a}}\)\(\ddot{\text{a}}\)\(\ddot{\text{a}}\)** & **Hel** & **Kolobrzeg** & **Leba** & \(\ddot{\text{S}}\)\(\ddot{\text{w}}\)\(\ddot{\text{u}}\)\(\ddot{\text{u}}\)\(\ddot{\text{j}}\)\(\ddot{\text{c}}\)** & **Szzecin** & **Ustka** \\  & **[hPa]** & **[hPa]** & **[hPa]** & **[hPa]** & **[hPa]** & **[hPa]** & **[hPa]** & **[hPa]** \\ \hline January & 1011.6 & 1012.0 & 1012.4 & 1011.8 & 1012.6 & 1013.1 & 1010.9 \\ February & 1014.9 & 1015.4 & 1015.0 & 1015.2 & 1016.0 & 1016.5 & 1014.4 \\ March & 1014.1 & 1014.8 & 1015.8 & 1014.5 & 1014.6 & 1014.8 & 1013.5 \\ April & 1015.1 & 1016.0 & 1016.5 & 1015.9 & 1015.9 & 1015.6 & 1015.0 \\ May & 1015.5 & 1016.4 & 1015.5 & 1016.2 & 1016.1 & 1015.9 & 1015.2 \\ June & 1015.0 & 1015.9 & 1015.6 & 1015.8 & 1015.6 & 1015.2 & 1014.8 \\ July & 1012.6 & 1013.3 & 1013.4 & 1013.3 & 1013.8 & 1013.8 & 1012.5 \\ August & 1013.8 & 1014.6 & 1013.9 & 1014.3 & 1014.1 & 1014.0 & 1013.3 \\ September & 1015.4 & 1016.1 & 1015.2 & 1015.9 & 1015.9 & 1016.0 & 1014.9 \\ October & 1013.3 & 1013.8 & 1012.8 & 1013.4 & 1013.3 & 1013.8 & 1012.3 \\ November & 1013.7 & 1014.2 & 1011.4 & 1013.6 & 1012.9 & 1013.3 & 1012.5 \\ December & 1011.1 & 1011.6 & 1010.4 & 1011.2 & 1011.1 & 1011.6 & 1010.1 \\ Yearly & 1013.8 & 1014.5 & 1014.0 & 1014.3 & 1014.3 & 1014.5 & 1013.3 \\ \hline \end{tabular}
\end{table} 
Table 1: Mean atmospheric pressure by selected ports, 2018–2023 [43]. periods of stable weather with no rain and slight wind; however, they may also lead to the formation of fog and mist, which restrict visibility [44]. Cyclones, or low-pressure systems, on the other hand, are characterized by strong winds, rapid weather changes, and frequent rains [45]. Moving cyclones have an impact on the variability of hydrological and meteorological conditions, causing sudden changes in sea levels and severe storms. Therefore, they may have a direct impact on the operation of the LNG infrastructure in the southern Baltic. Low-pressure systems are especially dangerous in autumn and winter seasons, when intensified convection processes lead to heavy storms and increased risk of icing of vessels' hulls [46]. A factor of great importance in an analysis of hydrological and meteorological conditions is precipitation, i.e., all and any solid and/or liquid products of water vapor condensation in the atmosphere [47; 48]. Precipitation has a direct impact on the salinity and temperature of surface waters and thus on the operational conditions of LNG terminals and shipping routes. Heavy rains may cause increased inflow of river water into the Baltic Sea and thus change the hydrological balance in the area, whereas heavy snow or freezing rain may impede LNG handling operations and call for adjustment of LNG storage and transport technologies to extreme weather conditions. Maximum daily precipitation occurring in Poland may be significantly higher (mostly three or four time higher) than the mean daily amount of water in the atmosphere (Table 2) [49]. Sunshine duration is defined as the number of hours in which sunshine directly reaches the Earth's surface in a certain area. Measured as a daily, monthly, or annual total, sunshine duration is an important indicator in meteorological and climatic analyses [50]. Sunshine duration depends on a number of astronomical, meteorological, and topographical factors [51; 52]. The most important of them are as follows:  
* Length of day--in the southern Baltic, the length of day varies between several hours in winter and a dozen or so hours in summer [53; 54];
* Cloudiness--the Baltic Sea is characterized by variable cloudiness, with mainly stratus and nimobstratus clouds in winter, which are conducive to rain and fog; summer periods also see cumulus clouds, which may bring thunderstorms [55];
* Terrain--diverse in the Baltic Sea and characterized by various geo-morphological features, such as beaches, spits, dunes, cliffs, bays, coves, and estuaries [56].