Spatial–Temporal Changes in Land Surface Temperature Pattern in the Western Edge of the Inner Hanoi City, Vietnam During the 2005–2019 Period

Abstract

Urbanization is a primary driver that leads to the increase of urban heat, including air temperature and surface temperature. Recently, Hanoi city has been experienced a high urbanization rate, especially at the edge of the inner city. In this study, the surface temperature bands of Landsat-5 and Landsat-8 Collection 2 Level-2 were directly utilized to calculate LST for the study area at the two selected years 2005 and 2019. Furthermore, the spatial–temporal changes in Land Surface Temperature (LST) in the period 2005–2019 were analyzed and the relationships between Normalized Land Surface Temperature (NLST) and the two indices NDVI (Normalized Difference Vegetation Index) and NDBI (Normalized Difference Built-up Index) were clarified. The study results indicated a significant increase in the mean LST and the mean NLST between 2005 and 2019. In fact, the mean LST rose from 33.18 to 38.06 °C and the mean NLST rose from 0.38 to 0.43. Additionally, a negative correlations between NLST and NDVI were explored at correlation coefficients (R) of −0.69 and −0.77 in 2005 and 2019, respectively. In contrast, a positive relationships between NLST and NDBI were shown at R-value of 0.74 and 0.85. The outcomes revealed the importance of vegetation in urban cooling and forces authorities to implement urban green space planning seriously.