J. Eur. Opt. Society-Rapid Publ. 22, 32( 2026) 329
Figure 5. Land surface temperature data.( a) Measured data( b) After OK interpolation.
Figure
6. Land surface elevation map.( a) Slope calculation results of land surface.( b) Aspect calculation results of land surface.( c) Elevation data.
location x 0 and time t i, which is obtained by solving the OK system of equations independently at each time step. The interpolated result is shown in Figure 5b.
2.4.2 Modulation of land surface temperature details
Land surface meteorological data can provide continuous 24-hour temperature variation information and has a high temporal resolution, but its spatial resolution is low, making it difficult to reflect temperature differences at the land surface scale. Therefore, it is necessary to combine meteorological station data with high spatial resolution land surface temperature data retrieved from Landsat 8 to construct a temperature extension model that complements temporal and spatial aspects, in order to achieve a refined spatiotemporal reconstruction of land surface temperature.
Because different land surfaces are located at different altitudes, slopes, and aspects, the atmospheric temperature, humidity, and solar radiation near different land surfaces are different, resulting in subtle fluctuations in temperature. Considering the modulating effect of complex terrain conditions on surface thermal processes, the in-fluence of topographic elevation on surface temperature is introduced in this paper. Key topographic factors such as slope, and aspect are extracted using a digital elevation model( DEM). A multiple linear regression model is constructed to characterize the modulation relationship between topographic parameters and the spatial distribution of surface temperature, thereby achieving a refined simulation of the detailed features of the temperature field.
The slope represents the tilt degree of a certain point on the surface, and the tilt degree of the terrain is measured by calculating the height change of adjacent pixels in two directions. The calculation formula [ 28 ] is as follows:
0sffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffi1 2 @ Z
Slopeðx; yÞ ¼ arctan þ @ Z 2 @
A @ x @ y ð13Þ
where @ Z and @ Z denote the elevation gradients in the x and y
@ x @ y
directions, respectively, which can be approximated by the differences between adjacent pixels. The slope direction represents the slope orientation of a certain point on the surface, and the main direction of the slope is usually calculated [ 28 ].
@ Z Aspectðx; yÞ ¼ arctan = @ Z ð14Þ
@ y @ x
The calculation results of slope and aspect are shown in Figures 6a and 6b. Figure 6c shows the elevation data.
The elevation information of the port background has a resolution of 30 m, which is matched with the spatial resolution of the Landsat8 remote sensing image. Multiple DEM raster data are mosaicked and clipped in ArcGIS to obtain