Greenland summer blocking characteristics: an evaluation of a high-resolution multi-model ensemble
Document Type
Article
Source of Publication
Climate Dynamics
Publication Date
1-1-2024
Abstract
Atmospheric blocking is a phenomenon that can lead to extreme weather events over a large region, yet its causes are not fully understood. Global climate models show limitations in representing Northern Hemisphere blocking, especially its frequency, and decadal variability in Greenland blocking in summer in the recent decades. In this study we evaluate the ability of high-resolution (HighResMIP) Earth System Models (ESMs) to simulate summer blocking over the Greenland area, using different but complementary methods to describe the characteristics of blocking. We find that the HighResMIP ensemble can reproduce the spatial pattern of Greenland blocking events, albeit with systematic biases, and capture the relative frequencies of the main blocking patterns: namely the wave breaking structure, North Atlantic ridge, and omega-type blocking. However, the HighResMIP ensemble fails to simulate the observed temporal variations of Greenland blocking index (GB2) and the extremely high values of daily GB2 observed in recent decades. In addition, we do not find clearly superior representation of blocking features from higher-resolution in HighResMIP models compared with lower-resolution models. We also find large sea surface temperature (SST) biases over the North Atlantic and seas surrounding Greenland, and biases in moisture transport over the North Atlantic toward Greenland, especially over the western flank of blocking areas, which might together contribute to model biases in the representation of blocking magnitude.
DOI Link
ISSN
Publisher
Springer Science and Business Media LLC
Disciplines
Physical Sciences and Mathematics
Keywords
Atmospheric Dynamics, Blocking, Climate Models, Greenland, Weather Regimes
Scopus ID
Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 International License.
Recommended Citation
Luu, Linh N.; Hanna, Edward; de Alwis Pitts, Dilkushi; Maddison, Jacob; Screen, James A.; Catto, Jennifer L.; and Fettweis, Xavier, "Greenland summer blocking characteristics: an evaluation of a high-resolution multi-model ensemble" (2024). All Works. 6864.
https://zuscholars.zu.ac.ae/works/6864
Indexed in Scopus
yes
Open Access
yes
Open Access Type
Hybrid: This publication is openly available in a subscription-based journal/series