Valenzuela et al. (2025) Atmospheric Water Vapor and Precipitation Coupling in Southwestern South America

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

Identification

• Journal: Geophysical Research Letters
• Year: 2025
• Date: 2025-12-16
• Authors: Raúl Valenzuela, Jorge Jara, Cristian Martínez-Villalobos
• DOI: 10.1029/2025gl119095

Research Groups

Not specified in the abstract.

Short Summary

This study analyzes 15–27 years of precipitable water vapor (PWV) and co-located precipitation data across southwestern South America to understand their long-term coupling across diverse latitudinal and climatic gradients. It reveals that the strength and functional form of PWV–precipitation coupling vary systematically with latitude and precipitation regime, with tropical Andes showing a power-law relationship and extratropical regions following a logistic form.

Objective

• To analyze the long-term variability of water vapor and its coupling with precipitation across strong latitudinal and climatic gradients in southwestern South America, addressing gaps in understanding beyond short records, tropical regions, or the Northern Hemisphere.

Study Configuration

• Spatial Scale: Southwestern South America, covering tropical, high-elevation convective, extratropical, and subpolar regions across significant latitudinal and climatic gradients.
• Temporal Scale: 15–27 years (long-term variability), with analysis across annual, monthly, daily, and seasonal timescales.

Methodology and Data

• Models used: Not explicitly mentioned; the study is based on observational data analysis.
• Data sources:
  • Precipitable Water Vapor (PWV) from Global Navigation Satellite Systems (GNSS).
  • Precipitation data from co-located rain gauges.

Main Results

• The strength of PWV–precipitation coupling varies systematically with latitude and precipitation regime.
• High-elevation convective regions exhibit strong PWV–precipitation coupling across all analyzed timescales.
• Extratropical areas, dominated by stratiform precipitation, show weaker annual and monthly coupling but moderate daily relationships.
• Seasonal PWV ranges from 40 mm in tropical regions to 6 mm in subpolar regions, while precipitation varies inversely with this trend.
• Probability distributions indicate a power-law PWV–precipitation relationship exclusively in the tropical Andes.
• Extratropical regions follow a logistic PWV–precipitation relationship, which is shaped by positively skewed PWV distributions.

Contributions

• Provides a long-term analysis (15–27 years) of water vapor and precipitation coupling, addressing a gap in studies often limited to short records, tropical regions, or the Northern Hemisphere.
• Systematically quantifies how PWV–precipitation coupling strength and functional forms (power-law vs. logistic) vary across strong latitudinal and climatic gradients in southwestern South America.
• Identifies distinct regional behaviors in coupling, linking them to precipitation regimes (convective vs. stratiform) and geographical location (tropical Andes vs. extratropical regions).

Funding

Not specified in the abstract.

Citation

@article{Valenzuela2025Atmospheric,
  author = {Valenzuela, Raúl and Jara, Jorge and Martínez-Villalobos, Cristian},
  title = {Atmospheric Water Vapor and Precipitation Coupling in Southwestern South America},
  journal = {Geophysical Research Letters},
  year = {2025},
  doi = {10.1029/2025gl119095},
  url = {https://doi.org/10.1029/2025gl119095}
}