## 1 Measurement and Analysis of Local Humidity
### Relationship between Local Humidity and Local Temperature in the Bay  
It can be seen from the humidity variation curves presented in Figure 2 that the local humidity of the bay dropped from around 8:40 to 16:30 during the day. Between 16:30 and 8:40 the following day, the local humidity of the bay increased and became stabilized. Comparing the local humidity curves obtained in this study with the previously published local temperature curves [23] leads to the conclusion that the pattern of variation in local humidity is correlated to the temperature turning points. More specifically, major changes in local humidity always occur 40 min to 1 h after a major change in local temperature. Therefore, in order to determine the degree of correlation between the local humidity and local temperature, the temperature and humidity variation curves for each bay were plotted in the same graph, as shown in Figure 3. The dotted lines represent humidity variations and the solid lines represent temperature. It can be seen from the graphs on the left side of Figure 3 that there is a large negative correlation between the humidity and temperature variations. The humidity drops as temperature rises and increases as temperature drops. Figure 3: _Cont._  
To assess the influence of local temperature on the local humidity in the bay, temperature and humidity data were processed using the following formulae:  
\[ \begin{array}{l}\Delta T_{kl}=T_{k}-T_{k+l}\\ \Delta h_{kl}=h_{k}-h_{k+l}\\ (l=0\,\sim\,n-1;\,k=1\,\sim\,n-l)\end{array}  \tag{1}\]  
where \(T_{k}\) and \(T_{k+l}\) are the \(k\)-th and \(k\)+1-th temperature values of the bay and \(h_{k}\) and \(h_{k+l}\) are the \(k\)-th and \(k\)+1-th humidity values, \(\Delta T_{kl}\) is the discrepancy between the two temperature values separated by \(l\) values, and \(\Delta h_{kl}\) is the discrepancy between the two humidity values separated by \(l\) values. Taking \(\Delta T_{kl}\) as the abscissa and \(\Delta h_{kl}\) as the Y-axis, the graph shows the relationship between the humidity and temperature variations in the bay. The data was then analyzed in MATLAB to obtain the graphs shown on the right side of Figure 3. The scatter plots correspond to values of \(\Delta T_{kl}\) and \(\Delta h_{kl}\), and the solid lines were fitted to the data using the least squares method based on temperature and humidity variation patterns. It can be seen that there is a large negative correlation between the rate of change of the local humidity and temperature in the bay. When the value of \(l\) in Equation (1) is zero, then \(\Delta T_{kl}\) and \(\Delta h_{kl}\) are both zero, which means that in theory, the lines of best fit, should pass through point (0, 0). The theoretical model of the fitted line should be a proportional model with a negative slope, that is  
\[\Delta h_{kl}=q_{i}\times\Delta T_{kl} \tag{2}\]  
where \(q_{i}\) is the slope and expresses the relationship between the rates of change of temperature and humidity of the \(i\)-th bay. Since there can be a multitude of influencing factors affecting the local humidity of the bay in real-world scenarios, some discrepancy will always exist between the actual fitting formula and the theoretical model, which is simply a linear model with an intercept value. Since the intercept value in the fitting formula is not large, it was not taken into account in the actual fitting formula used in this study, and instead \"coarse granularity principle\" for studying environmental spectrum was followed [24]. Figure 3: Curves of temperature-humidity relationship and rate of change of temperature and humidity of each bay. Figure 3 only shows the relationship between the local temperature and local humidity in the bay and the rate of change during a single day. To reveal a more general pattern, temperature and humidity data of 30 randomly selected days within one year were selected and processed using Equation (1), with the aim of fitting a relational expression to describe the rates of change of temperature and humidity for each bay.