Assessment of Abrupt Shifts in CMIP6 Models Using Edge Detection

Abstract Past research has shown that multiple climate subsystems might undergo abrupt shifts, such as the Arctic Winter sea ice or the Amazon rainforest, but there are large uncertainties regarding their timing and spatial extent. In this study we investigated when and where abrupt shifts occur in...

Full description

Saved in:
Bibliographic Details
Main Authors: Sjoerd Terpstra, Swinda K. J. Falkena, Robbin Bastiaansen, Sebastian Bathiany, Henk A. Dijkstra, Anna S. von derHeydt
Format: Article
Language:English
Published: Wiley 2025-06-01
Series:AGU Advances
Subjects:
Online Access:https://doi.org/10.1029/2025AV001698
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Abstract Past research has shown that multiple climate subsystems might undergo abrupt shifts, such as the Arctic Winter sea ice or the Amazon rainforest, but there are large uncertainties regarding their timing and spatial extent. In this study we investigated when and where abrupt shifts occur in the latest generation of earth system models (CMIP6) under a scenario of 1% annual increase in CO2. We considered 82 ocean, atmosphere, and land variables across 57 models. We used a Canny edge detection method to identify abrupt shifts occurring on yearly to decadal timescales, and performed a connected component analysis to quantify the spatial extent of these shifts. The systems analyzed include the North Atlantic subpolar gyre, Tibetan Plateau, land permafrost, Amazon rainforest, Antarctic sea ice, monsoon systems, Arctic summer sea ice, Arctic winter sea ice, and Barents sea ice. Except for the monsoon systems, we found abrupt shifts in all of these across multiple models. Despite large inter‐model variations, higher levels of global warming consistently increase the risk of abrupt shifts in CMIP6 models. At a global warming of 1.5°C, six out of 10 studied climate subsystems already show large‐scale abrupt shifts across multiple models.
ISSN:2576-604X