Work

Predictability of North Pacific blocking events: Analogue‐based analysis of historical MIROC6 simulations

Year: 2026

Type: article

Abstract: Atmospheric blocking exerts a profound influence on midlatitude circulation, yet its predictability remains elusive, due to intrinsic nonlinearities and sensitivity to initial conditions. While blocking dynamics have been extensively studied, the impact of geographical positioning on predictability remains largely unexplored. This study provides a comparative assessment of the predictability of western and eastern North Pacific blocking events, leveraging analogue‐based diagnostics applied to Coupled Model Intercomparison Project Phase 6 (CMIP6) Model for Interdisciplinary Research on Climate, version 6 (MIROC6) simulations. Blocking structures are identified using geopotential height gradient reversal, with their temporal evolution analyzed through trajectory tracking and error growth metrics. Results reveal that eastern blocks exhibit lower predictability, characterized by rapid error divergence and increased mean logarithmic growth rates compared with western blocks. Persistence analysis gives no significant difference between eastern and western North Pacific blocking events. Sensitivity analyses across varying detection thresholds validate the robustness of these findings.

Source: Quarterly Journal of the Royal Meteorological Society

DOI: 10.1002/qj.70104

Authors: Anupama K. Xavier, Oisín Hamilton, Davide Faranda, Stéphane Vannitsem

Institutions: Royal Meteorological Institute of Belgium, UCLouvain, Laboratoire de Météorologie Dynamique, Laboratoire des Sciences du Climat et de l'Environnement, London Mathematical Laboratory

Language: English

Topic: Climate variability and models

Subfield: Global and Planetary Change

Field: Environmental Science

Domain: Physical Sciences

Open Access status: hybrid

Estimated APC paid: $4,320

Funders: European Commission, Horizon 2020 Framework Programme