Liu et al. (2026) Urban Land Surface Effects on Summertime Clouds and Moist Convection in Houston Under Different Synoptic Conditions

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

Identification

• Journal: Journal of Geophysical Research Atmospheres
• Year: 2026
• Date: 2026-04-09
• Authors: Ye Liu, Yun Qian, Colleen Kaul, Brian Gaudet, Larry K. Berg, Z Feng, Adam C. Varble, Sheng‐Lun Tai, Ya‐Chien Feng, Zikun Yang, T. C. Chakraborty, Jerome D. Fast
• DOI: 10.1029/2025jd045131

Research Groups

Information not available from the abstract.

Short Summary

This study investigates the impact of the Houston metropolitan area on summertime cloud cover and convective cell characteristics using satellite observations, radar data, and high-resolution modeling. It reveals that urban land cover consistently enhances cloud fraction and convective activity, with these impacts being highly dependent on large-scale meteorological forcing.

Objective

• To investigate the impact of the Houston metropolitan area on summertime cloud cover and convective cell characteristics under different synoptic regimes.
• To isolate urban effects by comparing model simulations with realistic urban land cover against hypothetical scenarios where all urban areas are replaced by rural vegetation.

Study Configuration

• Spatial Scale: Houston metropolitan area and surrounding rural areas.
• Temporal Scale: Summertime.

Methodology and Data

• Models used: High-resolution process-based modeling.
• Data sources: Satellite observations, radar data.

Main Results

• Houston's land cover consistently enhances cloud fraction and convective activity relative to surrounding rural areas, with effects altered by large-scale meteorological forcing.
• Under weakly forced conditions, enhanced surface heat flux drives low-level convergence and vertical ascent, leading to an over 8% cloud fraction increase between 2 km and 6 km over the city.
• Under strongly forced conditions, urban influences manifest differently depending on cloud type:
  • For non-convective clouds, the city acts as a barrier, decelerating and lifting moist southerly inflow, increasing low cloud cover over the urban core while decreasing it downwind.
  • For convective clouds, both synoptic ascent and urbanization modulate moisture redistribution and cloud structure, producing modest cloud enhancement over the city and slight suppression over the downwind area.
• Urbanization exerts small changes in the intensity of convective cells but significantly decreases their duration and traveling distance.
• Urban impacts on clouds are highly regime-dependent.

Contributions

• Highlights the importance of accounting for land surface heterogeneity in modeling clouds and precipitation.
• Demonstrates that urban impacts on clouds are highly regime-dependent, providing new insights into the complex interactions between urban landscapes and atmospheric processes under varying synoptic conditions.
• Quantifies urban effects on cloud fraction, convective activity, and convective cell characteristics (duration, traveling distance) under different forcing conditions.

Funding

Information not available from the abstract.

Citation

@article{Liu2026Urban,
  author = {Liu, Ye and Qian, Yun and Kaul, Colleen and Gaudet, Brian and Berg, Larry K. and Feng, Z and Varble, Adam C. and Tai, Sheng‐Lun and Feng, Ya‐Chien and Yang, Zikun and Chakraborty, T. C. and Fast, Jerome D.},
  title = {Urban Land Surface Effects on Summertime Clouds and Moist Convection in Houston Under Different Synoptic Conditions},
  journal = {Journal of Geophysical Research Atmospheres},
  year = {2026},
  doi = {10.1029/2025jd045131},
  url = {https://doi.org/10.1029/2025jd045131}
}