Measuring the relationship of land use land cover, normalized difference vegetation index and land surface temperature in influencing the urban microclimate in northeast Delhi, India

Abstract

Urbanisation is a process for conversion of spaces into build up areas, long-term conversions led to shrinkage of open lands to unplanned growth for residential areas or commercial purposes to accommodate the increasing population. Open green spaces and parks have strategic role in regulate the urban environment and mitigate the effect of urban heat island (UHI). Also, its spatial arrangement in an area impacts the surface heating so their spatial distribution within the residential sectors, has become an integral part of sustainable development for the city. They have direct socio-cultural and health benefits by providing spaces for physical activity, social interaction, and fresh air, which depends upon the accessibility, quality, attractiveness, and regularity of people using it. In North East Delhi district, distribution of parks shows huge disparity between planned and unplanned residential areas which is impacting the surface temperature and micro climate. A quantitative analysis is used with Geo-informatics-based indexes of biophysical parameters for parks, vegetation quality (NDVI) and land surface temperature distribution (LST) with the land use pattern for accessing the impact of parks on mitigating the heat island effect. The result obtained from analysis shows a negative relation between the LST and NDVI. The unplanned regions have big parks with negative NDVI values (-0.04) lacking vegetation cover and are poorly maintained and accessed by many people, on the other hand the parks with NDVI values (0.12) are well distributed in planned colonies and maintained. Maximum of the existing parks is below 10km² area and has poor quality. This study shows healthy vegetation in parks is important for wellbeing of the city rather than merely open spaces.