Details

Autor(en) / Beteiligte

• Wang, Jie
• Miao, Shiguang
• Doan, Quang‐Van
• Chen, Fei
• Abolafia‐Rosenzweig, Ronnie
• Yang, Long
• Zhang, Guwei
• Zhang, Yizhou
• Dou, Jingjing
• Xu, Youpeng

Titel

Quantifying the Impacts of High‐Resolution Urban Information on the Urban Thermal Environment

Ist Teil von

• Journal of geophysical research. Atmospheres, 2023-03, Vol.128 (6), p.n/a

Ort / Verlag

Washington: Blackwell Publishing Ltd

Erscheinungsjahr

2023

Quelle

Wiley-Blackwell Journals

Beschreibungen/Notizen

• Detailed urban information, including land use/land cover (LULC), anthropogenic heat (AH) release, and urban canopy parameters (UCP), play critical roles in meteorological field simulations. It is particularly relevant for the Weather Research and Forecasting (WRF) model coupled with the single‐layer urban canopy model (SLUCM). Thus, we develop high‐resolution LULC, AH, and UCP data sets for Nanjing, a megacity in China, and conduct a series of numerical experiments with WRF/SLUCM to evaluate the impacts of urban parameters on the urban thermal environment. Model simulations with LULC scenarios have good agreement with the observed 2‐m temperature T2 $\left({T}_{2}\right)$ with a correlation coefficient of around 0.85, and present strong spatial homogeneity due to the more realistic representation of urban categories. The LULC change directly decreases the surface wind speed and increases (decreases) the sensible (latent) heat flux (QSH ${Q}_{SH}$ (QLH ${Q}_{LH}$)) in urban areas during the daytime; meanwhile increases QSH ${Q}_{SH}$ and releases ground heat storage (QGH ${Q}_{GH}$) during the nighttime, resulting in urban warming by 0.91°C in urban areas, compared with the control simulation (CTL) that does not take into account urban surfaces. In the LULC experiments combined with the UCP or AH, the UCP change enhances QSH ${Q}_{SH}$ and releases more QGH ${Q}_{GH}$ during nighttime, which increases T2 ${T}_{2}$ by 0.13°C relative to LULC simulation. Also, the UCP effect reduces surface roughness and increases the width of the urban canopy, resulting in slightly enhanced wind speed, which is favorable for a warming environment in the urban area; the AH change contributes to increasing T2 ${T}_{2}$ by 0.19°C through directly enhancing QSH ${Q}_{SH}$ relative to LULC simulation. AH combined with the UCP further strengthens the UCP effect in the urban area. Overall, the influence of urban parameters on the T2 ${T}_{2}$ is more pronounced during nighttime than daytime, which presents a decreasing trend with an increase in wind speed and spatial humidity in the urban area. Plain Language Summary Detailed information, describing urban land cover/land cover, anthropogenic heat release, and urban canopy parameters can considerably influence the urban thermal environment. However, the effect and the inter‐comparison of these parameters have not been comprehensively investigated. In this study, we develop a high‐resolution urban information data set for a megacity in China, Nanjing, and conduct a series of numerical experiments with WRF/SLUCM to evaluate the sensitivity of the urban thermal environment to the newly developed data set. We find that the urban thermal environment is most sensitive to urban land use, relative to nonurban scenarios. The relative contributions of urban land cover/land cover, anthropogenic heat release, urban canopy parameters, and anthropogenic heat release combined with urban canopy parameters on the average 2‐m air temperature over the urban area are 54.82% (0.91°C), 11.45% (0.19°C), 7.83% (0.13°C), and 25.9% (0.43°C), respectively. These effects are more pronounced during nighttime than daytime, and present a decreasing trend with wind speed and spatial humidity increasing. This study provides insights on the impacts of urban information on the urban thermal environment and demonstrates the vital role of urban information in modeling urban temperature. Key Points High‐resolution land use/land cover (LULC), anthropogenic heat (AH), and urban canopy parameters (UCP) data sets are developed to examine the impacts of urban information on the urban thermal environment Relative contributions of LULC, AH, UCP, and AH + UCP on the 2‐m temperature (T2 ${T}_{2}$) are 54.82% (0.91°C), 11.45% (0.19°C), 7.83% (0.13°C), and 25.9% (0.43°C), respectively LULC and UCP impact T2 ${T}_{2}$ by changing thermal and dynamical fields, while AH directly affects T2 ${T}_{2}$ by enhancing sensible heat flux