Deng (2025) Nonlinear influence of coexisting CO ₂ and anthropogenic aerosols on East Asian summer precipitation through a mid-high-latitude pathway

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

Identification

Journal: Environmental Research Letters
Year: 2025
Date: 2025-11-18
Authors: Jiechun Deng
DOI: 10.1088/1748-9326/ae20a8

Research Groups

Information not available from the abstract.

Short Summary

This study investigates the nonlinear effects of coexisting increased carbon dioxide (CO₂) and anthropogenic aerosols (AAs) on summer precipitation over East Asia, revealing that their combined forcing leads to a nonlinear increase in North China precipitation, driven by remote nonlinear climate responses originating from the Arctic and North Atlantic via Rossby wave propagation.

Objective

To clarify how the coexistence of CO₂ and anthropogenic aerosols causes nonlinear effects on summer precipitation over East Asia.

Study Configuration

Spatial Scale: East Asia (EA), North China, Arctic, North Atlantic, East Siberian–Beaufort Seas, Eurasia.
Temporal Scale: July–August (for precipitation changes), general climate responses.

Methodology and Data

Models used: Fully coupled climate model simulations.
Data sources: Output from fully coupled model simulations.

Main Results

When both CO₂ and anthropogenic aerosol forcings are included, precipitation over North China in July–August decreases less than the linear combination of changes induced by individual forcings, indicating a nonlinear increase in precipitation.
These nonlinear changes over East Asia originate from the Arctic and North Atlantic region.
The Arctic sea-ice sensitivity to CO₂-induced warming is higher than to AA-induced cooling, leading to a large increase of sea ice concentration over the East Siberian–Beaufort Seas in the nonlinear effect.
This sea ice change excites an anomalous atmospheric Rossby wave propagating southeastward into the North Atlantic.
This wave increases low cloudiness, cooling the surface over the midlatitude North Atlantic.
The cooling subsequently generates an anomalous Rossby wave train pattern across Eurasia with two branches propagating toward East Asia.
Concurring circulation changes over East Asia ultimately result in the observed nonlinear precipitation changes.

Contributions

Suggests that nonlinear climate responses in high latitudes can remotely induce nonlinear changes in lower latitudes.
Highlights the critical need to consider nonlinear effects when analyzing externally forced climate changes, particularly over regions like East Asia.
Provides a mechanistic understanding of how coexisting CO₂ and anthropogenic aerosols lead to nonlinear precipitation changes over East Asia through remote teleconnections.

Funding