# Assessing Spatiotemporal LST Variations in Urban Landscapes Using Diurnal UAV Thermography
## 4 Results
### GWR Results  
Following the [PERSON]'s \(I\) analysis, which demonstrated significant spatial autocorrelation in LST across various LULC classes and diurnal periods, GWR was applied to explore the spatially varying relationships between LULC proximity and LST. The results of the GWR analysis are presented in both graphical and tabular formats to provide a comprehensive view of the spatial and temporal dynamics. Figure 8 displays a heat map of \(R^{2}\) values, offering a visual representation of the model's explanatory power across different LULC classes and timeframes. In parallel, Table 3 details the optimal bandwidth settings and corresponding adjusted \(R^{2}\) values for each LULC class across time periods. These metrics define the spatial scale at which local regression relationships are estimated and highlight the model's explanatory power, along with its variations across different times of the day. For areas dominated by bare soil, the strength of the spatial relationship with temperature varies considerably throughout the day. In the morning, the GWR model for bare soil explains approximately 14% of the variance (adjusted \(R^{2}\approx 0.14\), \(R^{2}\approx 0.24\)), suggesting a moderate level of local explanatory power. However, during the afternoon, the explanatory power drops dramatically (adjusted \(R^{2}\approx-0.05\), \(R^{2}\approx 0.03\)), which implies that factors other than proximity to bare soil may be more influential during this period, or that the relationship is more complex and less linear. In contrast, the evening and midnight periods show a substantial improvement in model fit (adjusted \(R^{2}\approx 0.515\) and \(0.460\), respectively), indicating that bare soil proximity is more strongly associated with temperature variations later in the day. The GWR bandwidth for bare soil also varies (ranging from 67 in the morning to 94 in the afternoon), suggesting that the spatial scale over which bare soil influences temperature is not constant and may depend on diurnal environmental processes. For built-up areas, the GWR models consistently capture a moderate proportion of the variance in temperature across all timeframes. The morning model (adjusted \(R^{2}\approx 0.149\), \(R^{2}\approx 0.23\)) and the afternoon model (adjusted \(R^{2}\approx 0.162\), \(R^{2}\approx 0.24\)) indicate a similar level of association. There is a modest increase in the model performance during the evening (adjusted \(R^{2}\approx 0.231\), \(R^{2}\approx 0.29\)) and midnight (adjusted \(R^{2}\approx 0.255\), \(R^{2}\approx 0.32\)) timeframes. Figure 8: Heatmap of local \(R^{2}\) values from GWR models evaluating the spatially varying influence of LULC proximity on LST. Color intensity corresponds to the magnitude of the local \(R^{2}\) values, with darker shades indicating stronger local explanatory power. The relatively stable but slightly increasing adjusted \(R^{2}\) values suggest that the influence of proximity to buildings on temperature might become slightly more pronounced later in the day, possibly due to heat retention and nocturnal cooling dynamics. The bandwidth values (ranging from 79 to 94) imply that the spatial extent of the building-related effects is moderately broad. Grasslands display the weakest and most inconsistent relationships with temperature. In the morning, the model explains only about 6% of the variance (adjusted \(R^{2}\approx 0.057\), \(R^{2}\approx 0.14\)). The afternoon period shows better performance (adjusted \(R^{2}\approx 0.227\), \(R^{2}\approx 0.30\)), but the evening and midnight models drop again to adjusted \(R^{2}\) values of approximately 0.030 and \(-0.010\), respectively. The negative adjusted \(R^{2}\) value for the grassland midnight model (\(-0.010\)) indicates that this model performs worse than a simple average in explaining LST variations, suggesting that, at midnight for grasslands, proximity to the considered LULC types is not a useful predictor of temperature.