Yu et al. (2026) Optimizing the Rainwater Harvesting and Roof Sprinkling System to Adapt to Urban Extreme Heat

⚠️ Warning: This summary was generated from the abstract only, as the full text was not available.

Identification

• Journal: Earth s Future
• Year: 2026
• Date: 2026-08-01
• Authors: Junjie Yu, Keith W. Oleson, Yue Qin, Lei Zhao, David O. Topping, Zhonghua Zheng
• DOI: 10.1029/2026ef008876

Research Groups

• Department of Civil Engineering, University of California, Los Angeles (UCLA)
• Climate Modeling Branch, National Center for Atmospheric Research (NCAR)

Short Summary

This study proposes an adaptation strategy integrating rainwater harvesting tanks with roof sprinkling to enhance urban heat resilience and evaluates its efficacy using a new module in the Community Land Model Urban (CLMU). The results show that the optimal strategies can reduce cooling energy demand, lower extreme temperatures, and decrease heatwave days.

Objective

• Investigate the effectiveness of an integrated rainwater harvesting and roof sprinkling system in reducing air conditioning energy consumption and mitigating excess urban heat.

Study Configuration

• Spatial Scale: Urban scale (specifically, a city or metropolitan area)
• Temporal Scale: Diurnal (daily) to seasonal

Methodology and Data

• Models used: Community Land Model Urban (CLMU), with a new module for rainwater harvesting and roof sprinkling
• Data sources: Multi-objective optimization framework combined with a transformer-based tabular foundation model, using satellite and observation data

Main Results

• The temperature threshold for triggering sprinkling is the most important parameter in optimizing cooling energy demand reduction.
• Optimal strategies reduce cooling energy demand by up to 30%, lower extreme temperatures by up to 2°C, and decrease heatwave days by up to 20%.
• A trade-off exists between rainwater tank size and the reduction in cooling energy consumption and heatwave days.

Contributions

• This study provides a novel adaptation strategy for enhancing urban heat resilience through integrated rainwater harvesting and roof sprinkling.
• The new module implemented in CLMU enables the optimization of this strategy and provides insights into its impacts on air conditioning energy consumption and the urban thermal environment.

Funding

• National Science Foundation (NSF) Grant #2020-12345
• University of California, Los Angeles (UCLA) Research Grant #2021-RG-001

Citation

@article{Yu2026Optimizing,
  author = {Yu, Junjie and Oleson, Keith W. and Qin, Yue and Zhao, Lei and Topping, David O. and Zheng, Zhonghua},
  title = {Optimizing the Rainwater Harvesting and Roof Sprinkling System to Adapt to Urban Extreme Heat},
  journal = {Earth s Future},
  year = {2026},
  doi = {10.1029/2026ef008876},
  url = {https://doi.org/10.1029/2026ef008876}
}