Analysis of air temperature reduction and indirect carbon savings by strategies of urban green space creation

Green spaces contribute significantly to carbon neutrality, specifically by indirectly reducing carbon emissions through the cooling effect. Existing studies have primarily focused on energy savings based on simple scenarios, resulting in a limited understanding of carbon reduction effects and specific planting strategies. To address this gap, this study analyzed the indirect carbon reduction effects of green space strategies in high-density urban areas. Using a university campus as a case study, nine green space creation strategies were designed and simulated using ENVI-met to quantify air temperature reduction and the subsequent indirect carbon reduction effects. The analysis results are as follows: (1) The Adding street trees strategy demonstrated the highest air temperature reduction effect, primarily by enhancing shading on impervious surfaces. Additionally, rooftop and facade greening strategies were effective in maintaining cooling effects even at higher vertical levels. (2) The maximum indirect carbon savings achieved through the cooling effect amounted to 361.36 kgCO₂ at 16:00, which corresponds to approximately 8.55% of the campus's electricity consumption. These findings demonstrate that university campuses serve as 'Green Hubs' in high-density city centers. Furthermore, this study suggests that policymakers should accelerate the transition toward carbon neutrality by adopting spatially tailored greening strategies based on analytical data.