Wang et al. (2026) Distinct Response of Summer Rainfall Anomalies over East Asia to the Interannual Variability of the Annual Cycle of East Asian Summer Monsoon

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

Identification

• Journal: Journal of Climate
• Year: 2026
• Date: 2026-01-12
• Authors: Ting Wang, Shuangmei Ma, Congwen Zhu
• DOI: 10.1175/jcli-d-25-0524.1

Research Groups

Not explicitly mentioned in the provided abstract.

Short Summary

This study investigates the distinct response of May-September rainfall anomalies to East Asian summer monsoon (EASM) annual cycle phase anomalies, identifying two dominant modes linked to different ENSO patterns. This research provides new insights for seasonal rainfall forecasting, particularly over North China and the Korean Peninsula.

Objective

• To investigate the distinct response of rainfall anomalies during May–September to the phase anomalies (onset, peak, and withdrawal) of the annual cycle in the East Asian summer monsoon (EASM).

Study Configuration

• Spatial Scale: East Asia, specifically focusing on North China, Yangtze River, Japan Island, Korean Peninsula, south of the Yangtze River, North and Northwest China, and Northeast China.
• Temporal Scale: 1961–2023 (63 years), focusing on May–September rainfall anomalies and interannual variability of EASM phase anomalies.

Methodology and Data

• Models used: Not explicitly mentioned in the provided abstract. The study appears to be based on analysis of observed or reanalysis data.
• Data sources: East Asian monsoon index, rainfall anomaly data, and atmospheric circulation data (e.g., Western North Pacific subtropical high, WNPSH), likely derived from observational or reanalysis datasets. Information on El Niño–Southern Oscillation (ENSO) events (La Niña, El Niño, and transitions) is also utilized.

Main Results

• Rainfall anomalies over North China, the Yangtze River, Japan Island, and the Korean Peninsula are significantly regulated by the interannual variability of EASM onset and withdrawal.
• The phase anomalies of EASM can be decomposed into two dominant modes:
  • First Mode: Characterized by a prolonged (shortened) duration of EASM. This mode leads to a decrease (increase) in rainfall anomalies south of the Yangtze River in May, July, and September. It is driven by persistent La Niña (El Niño) conditions prevailing from the preceding winter to summer, which weakens (strengthens) the WNPSH in May and strengthens (weakens) with a northward (southward) shift in July and September.
  • Second Mode: Primarily reflects a delayed (advanced) peak of EASM. This mode results in a significant increase (decrease) in rainfall anomalies south of the Yangtze River in June, the Yangtze River valley in July, North and Northwest China in August, and Northeast China in September. It is linked to El Niño–La Niña (or vice versa) transitions from the preceding winter to summer, where the WNPSH strengthens (weakens) before July but weakens (strengthens) after August.
• The phase anomalies of EASM show a strong linkage with El Niño–Southern Oscillation (ENSO) in winter.

Contributions

• Provides a novel perspective by linking ENSO and rainfall from the viewpoint of the phase anomalies of the EASM annual cycle, an area less explored in previous literature.
• Identifies and demonstrates the distinct effects of the two leading phase modes of the EASM annual cycle on monthly rainfall anomalies across East Asia.
• Offers new insights and a new clue for seasonal summer rainfall forecasting, particularly over North China and the Korean Peninsula, by connecting EASM phase anomalies to winter ENSO conditions.

Funding

Not explicitly mentioned in the provided abstract.

Citation

@article{Wang2026Distinct,
  author = {Wang, Ting and Ma, Shuangmei and Zhu, Congwen},
  title = {Distinct Response of Summer Rainfall Anomalies over East Asia to the Interannual Variability of the Annual Cycle of East Asian Summer Monsoon},
  journal = {Journal of Climate},
  year = {2026},
  doi = {10.1175/jcli-d-25-0524.1},
  url = {https://doi.org/10.1175/jcli-d-25-0524.1}
}