Mu et al. (2025) Waveguide Teleconnection Mechanisms Driving Summer Compound Heat‐Humidity Extremes in China Land Monsoon Region

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

Identification

• Journal: Journal of Geophysical Research Atmospheres
• Year: 2025
• Date: 2025-10-03
• Authors: Jiayi Mu, Qianrong Ma, Shujuan Hu, Taichen Feng, Rui Hu, Pengcheng Yan, Guolin Feng
• DOI: 10.1029/2025jd043884

Research Groups

Not explicitly stated in the abstract.

Short Summary

This study reveals consistently increasing trends of summer compound heat-humidity extremes (CHHEs) across the China Land Monsoon (CLM) region from 1961–2022, attributing this rise to a weakening British Okhotsk Corridor (BOC)-Silk Road Pattern (SRP) nexus since 2000, which is modulated by North Atlantic sea surface temperature anomalies.

Objective

• To reveal the trends of summer compound heat-humidity extremes (CHHEs) across the China Land Monsoon (CLM) region during 1961–2022.
• To investigate the atmospheric and teleconnection mechanisms, particularly the role of the British Okhotsk Corridor (BOC)-Silk Road Pattern (SRP) nexus and North Atlantic sea surface temperature anomalies, in regulating CHHEs variability in the CLM region.

Study Configuration

• Spatial Scale: China Land Monsoon (CLM) region, with specific focus on the northeast and southwest sub-regions.
• Temporal Scale: 1961–2022 (62 years) for CHHEs trends; "since 2000" for BOC-SRP nexus shift; 13-year sliding correlations for teleconnection analysis.

Methodology and Data

• Models used: Community Earth System Model (CESM) simulations (used to confirm modulation of BOC-SRP nexus).
• Data sources: Wet-bulb globe temperature (used as an indicator for CHHEs, derived from unspecified observational or reanalysis data for the period 1961–2022).

Main Results

• Summer compound heat-humidity extremes (CHHEs) exhibited consistently increasing trends across the China Land Monsoon (CLM) region during 1961–2022, with significant increases observed in the northeast and southwest.
• Since 2000, the British Okhotsk Corridor (BOC)-Silk Road Pattern (SRP) nexus shifted from a strong to a weak state, significantly influencing CHHEs variability.
• During the weak BOC-SRP nexus period:
  • In northern China, particularly northeastern CLM, an anomalous high-pressure system dominated, intensified by negative potential vorticity anomalies through subsidence and diabatic heating. Simultaneously, abundant moisture transport from the western Pacific reinforced hot and humid conditions, jointly increasing CHHEs.
  • Over southwestern CLM, the high-pressure system strengthened anomalous easterlies, which, along with negative vorticity advection, increased moisture divergence. Additionally, meridional temperature advection promoted warm air accumulation in the lower troposphere, further increasing CHHEs.
• The weak BOC-SRP nexus is modulated by North Atlantic tripole sea surface temperature anomalies through Rossby wave energy divergence, a mechanism confirmed by Community Earth System Model simulations.

Contributions

• Highlights the critical role of mid- to high-latitude teleconnections' variable coupling states (specifically the BOC-SRP nexus) in regulating CHHEs in the CLM region.
• Identifies a significant shift in the BOC-SRP nexus since 2000 and details its impact on CHHEs variability.
• Provides specific atmospheric mechanisms (e.g., high-pressure systems, potential vorticity anomalies, moisture transport, temperature advection) explaining the increase in CHHEs in different CLM sub-regions under a weak BOC-SRP nexus.
• Demonstrates the modulation of the BOC-SRP nexus by North Atlantic tripole sea surface temperature anomalies via Rossby wave energy divergence, supported by model simulations.

Funding

Not explicitly stated in the abstract.

Citation

@article{Mu2025Waveguide,
  author = {Mu, Jiayi and Ma, Qianrong and Hu, Shujuan and Feng, Taichen and Hu, Rui and Yan, Pengcheng and Feng, Guolin},
  title = {Waveguide Teleconnection Mechanisms Driving Summer Compound Heat‐Humidity Extremes in China Land Monsoon Region},
  journal = {Journal of Geophysical Research Atmospheres},
  year = {2025},
  doi = {10.1029/2025jd043884},
  url = {https://doi.org/10.1029/2025jd043884}
}