Assessing the Cooling Effect of Urban Cemeteries in Samsun, a Black Sea Metropolis

Urban cemeteries are a critical component of green infrastructure, providing innumerable ecosystem services. Although they are often recognized for their cultural and religious functions, their microclimatic impacts have received comparatively little attention relative to those of other urban green spaces. This study aims to quantify the land surface cooling effect of three large urban cemeteries in Samsun, one of the Black Sea metropolises, during summer. Using thermal and spectral data from Landsat 8, surface temperatures and vegetation index values were retrieved in the study areas, and the correlation between them was assessed. Multiple buffer zone analyses, land surface temperature (LST) profiles and a piecewise regression model were utilized to quantitatively determine the cooling performance of cemeteries. The results point to them functioning as significant cold spots within the urban landscape. They reduced LST in their surroundings by up to 2.5°C–2.8°C (temperature drop amplitude). Specifically, Samsun Asri Cemetery (C1) and Kıranköy Cemetery (C2) produced a 2.1°C reduction within the first 100 metres of the cemetery boundary and a 2.5°C reduction within the first 250 metres, while piecewise regression confirmed comparable amplitudes of 2.8°C (C1) and 2.5°C (C2). A strong negative correlation was found between the NDVI and LST in all three cemeteries. The results of the study highlight that, in addition to the cultural function most commonly attributed to urban cemeteries, they also serve as microclimate regulators. Thus, urban cemeteries are a fundamental element in mitigating the urban heat island effect and should not be overlooked in urban planning.