Rapid urbanization and changing climatic conditions play a significant role in increasing temperature in urban environments due to the phenomenon of the Urban Heat Island (UHI) effect. In the future, this phenomenon will take place in megacities like Delhi on a large scale with a high population growth rate. In the current study, we analyzed the seasonal changes in green spaces and water bodies and their associated land surface temperature (LST) in the years 1992 and 2023 using Google Earth Engine (GEE). The % area change of the green spaces (GS) significantly increased in every season, whereas the % change in water bodies decreased in every season except the post-monsoon season. One important finding concluded that the LST of GS and water bodies (WB) and the average LST of the Delhi region continuously increased in the last 31 years. This indicates that anthropogenic activities significantly contributed to UHI and surpassed the urban cooling island (UCI) impacts of GS and WB. The results concluded that the post-monsoon season was found with a higher share of GS (431.81 km2) and WB (13.29 km2) than that of other seasons in the year 2022–2023. The landscape matrices of urban GS like Mean Patch Size (MPS), Percent Cover (PC), and Largest Patch Index (LPI) were found to be highest (0.13 ha, 29.06%, and 8.8%, respectively) in the post-monsoon season and lowest (0.06 ha, 6.31%, and 0.33%, respectively) in the pre-monsoon season. The results of the study showed significant relevance with “India’s Smart Cities Mission” (ISCM), in which the area of GS and WB can be specified over a certain population. The study provides insight into the decreasing efficacy of GS and WB due to the influence of anthropogenic and changing climatic conditions. This leads to more areas of GS and WB being required in the coming years due to changing climatic conditions and anthropogenic burdens over the city.