TOPOGRAPHIC INFLUENCE ON SPATIAL DISTRIBUTION OF PRECIPITATION AND SURFACE TEMPERATURE IN THE CASE OF BAKHMAL DISTRICT, JIZZAKH REGION

Abstract

This study quantifies the topographic control on the spatial distribution of surface temperature and precipitation in the Bakhmal District of the Jizzakh Region, Uzbekistan. We combined MODIS LST (MOD11A2, 2001–2024), the SRTM DEM, and CHIRPS daily precipitation to (i) derive annual mean Land Surface Temperature (LST), (ii) stratify the terrain into elevation belts, and (iii) evaluate the roles of elevation and slope in shaping hydrothermal patterns. Annual mean LST ranged from ~17 to 22 °C, whereas annual precipitation varied between ~315 and 720 mm yr⁻¹. A strong inverse temperature lapse was detected: the linear model LST = 30.57 – 0.00696·Elevation (°C; Elevation in m) explained 90.4% of LST variance (R²=0.9039), equivalent to ~0.70 °C cooling per 100 m rise in elevation. In contrast, the relationship between mean precipitation and slope was weak (R²=0.0169), with a fitted line P = 500.11 + 2.88·Slope (mm; Slope in degrees), indicating that synoptic circulation and moisture pathways likely dominate over local slope effects at this scale. The results demonstrate that elevation is the primary determinant of thermal gradients in Bakhmal, while precipitation responds only marginally to relief. The framework provides transferable evidence for agroclimatic zoning, drought-risk screening, and terrain-aware land management in semi-arid mountain foothills of Central Asia.