## 2 Materials and Methods
### Meteorological Factors
Therefore, close monitoring of meteorological conditions and implementation of appropriate warning systems is of utmost importance for safe navigation and effective shipping operations in the region under analysis [63]. Another phenomenon that strongly determines weather conditions is wind, defined in climatology as the horizontal movement of air masses relative to the Earth's surface. The occurrence of wind is closely related to the distribution of barometric pressure, and, more precisely, the horizontal and vertical gradients of barometric pressure. The greater the differences in barometric pressure in a certain area and the smaller the distance between isobars, the stronger and faster the flow of air. Speed and direction of wind are also affected by the Coriolis force, friction against the Earth's surface, and local topographic conditions [63; 64; 65]. Based on the available data, the highest wind speeds on the Polish coast occur in winter and are related to the presence of deep low-pressure systems and strong frontal systems (Figure 3). The lowest wind speeds are observed in late spring and summer, when the air pressure gradient is lower and the weather is less variable. Air humidity has a major impact on weather conditions and the climate. It affects the perceived temperature and the transportation of heat and humidity in the atmosphere. Air humidity is defined as the amount of water vapor in the atmosphere [68; 69]. Air humidity strongly influences meteorological processes, such as condensation, vaporing, and formation of clouds and precipitation [70]. One of the basic parameters of air humidity is relative humidity, expressed as the percentage of water vapor in the air relative to the maximum amount of water vapor air may contain at a certain temperature. An increase in temperature amplifies the capability of air to hold moisture, whereas a decrease in temperature is conducive to condensation [71; 72; 73; 74; 75]. Figure 3: Mean wind speed by selected ports, 2013–2023 [66; 67]. Relative humidity is an important factor in the analysis of hydrological and meteorological conditions in the southern part of the Baltic Sea, as it affects the rate of change in atmospheric conditions, which has an impact on the safety of navigation and the operation of the LNG infrastructure (Table 5) [77]. All of the meteorological factors mentioned above play a crucial role in shaping the hydrological and meteorological conditions in the southern part of the Baltic Sea. Analyzing and forecasting them are of utmost importance for the safety of LNG handling and efficient management of the LNG transportation and storage infrastructure. Meteorological conditions in the southern Baltic Sea significantly constrain the operational feasibility of LNG bunkering by imposing both technical and logistical limitations. Wind speeds exceeding 15-20 m/s represent a critical safety threshold established by international standards beyond which bunkering operations must be suspended due to the risk of hose failure and vessel instability. Analysis of long-term meteorological data indicates that such wind speeds occur, on average, during 15-25% of days per month in the winter season (November-March), particularly in exposed areas, such as the Gulf of Gdansk and off of the coast near Ustka. Sea state presents an additional challenge; wave heights exceeding 2.5 m interfere with safe mooring and the stability of connections between bunkering vessels and terminal infrastructure. These conditions are typically observed during 10-15 days per month in storm-prone periods. Similarly, reduced visibility below 500 m--most frequently caused by fog or heavy precipitation in autumn and winter--necessitates the suspension of operations in accordance with IMO regulations and Baltic port safety protocols. Icing is another critical constraint. When air temperatures drop below \(-5\)\({}^{\circ}\)C and relative humidity exceeds 90%, the risk of ice formation on cryogenic systems increases substantially.