Comparing Near-Surface and Subsurface Conditions to Determine Impacts of Green Spaces in Urban/Suburban Areas
Loading...
Date
2025-05
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
The Ohio State University
Abstract
As urbanization continues to increase globally, so too does the expansion of impervious surfaces like asphalt. Urban areas are associated with buildings built close together, high population density, and large areas of impervious concrete and asphalt. These characteristics, along with many others, tend to increase near-surface and subsurface temperatures as compared with nearby rural environments. This is known as the urban heat island (UHI) effect. The UHI affects individuals living in cities by impacting their health, raising cooling costs, and increasing heat stress on infrastructure. The UHI is caused by changes in surface radiation flux due to anthropogenic surface materials. The purpose of this study is to investigate and compare the effects of asphalt and grass surfaces on radiation flux, near-surface temperature, and soil moisture to assess the importance of green space in urban settings. This study will identify the advantages of urban vegetation. Specifically, these data were measured over a two-week period during October, in Dublin, Ohio which is just outside of Columbus. This study quantified how different land covers influenced the local microclimate and UHI. This study found that asphalt was on average 0.37°C warmer than grass, with a maximum daytime difference of +1.41°C and nighttime difference of -1.48°C. Grass lost more soil moisture daily (0.0215%) compared to asphalt (0.0085%), and absorbed significantly more moisture during rainfall, peaking at 0.214 m³/m³ versus asphalt’s 0.17 m³/m³. Although radiation data were likely flawed, asphalt showed higher outgoing shortwave radiation than grass, contrary to expected albedo-based behavior. Despite these differences, temperature and soil moisture data between surfaces showed strong correlations but statistical differences. These findings provide valuable information for urban planning and climate adaptation strategies for the future development of cities.
Description
Keywords
Meteorology, Microclimate, Surface Boundary Layer, Subsurface Boundary Layer, Greenspaces