Oceanic maintenance of atmospheric blocking in wintertime in the North Atlantic
File(s)s00382-024-07196-0.pdf (9.18 MB)
Published version
Author(s)
Mathews, Jamie
Czaja, Arnaud
Type
Journal Article
Abstract
The connection between atmospheric blocking over the North Atlantic and the diabatic influence of the Gulf Stream is investigated using potential vorticity and moist potential vorticity diagnostics in the ERA5 reanalysis data set during wintertime (1979 - 2020). In line with previous research, the reliance atmospheric blocking has on turbulent heat fluxes over the Gulf Stream and its extension, for induction and maintenance, is shown to be significant. The air-sea heat flux generates negative potential vorticity air masses in the atmospheric boundary layer. These air masses subsequently contribute to the block’s negative potential vorticity anomaly at upper levels through ascending motion in the warm conveyor belt. It is shown that the block’s size and frequency partially depends on oceanic preconditioning via anomalous oceanic heat transport and heat content, prior to the blocking event, both of which allow for stronger turbulent heat fluxes. It is further hypothesized that the block feeds back positively on itself through the advection of cold dry air over the Gulf Stream, sustaining this air-sea interaction. This in turn decreases ocean heat content, eventually halting this air-sea interaction and severing the atmospheric block from its maintenance pathway.
Date Issued
2024-07
Date Acceptance
2024-03-09
Citation
Climate Dynamics, 2024, 62 (7)
ISSN
0930-7575
Publisher
Springer
Journal / Book Title
Climate Dynamics
Volume
62
Issue
7
Copyright Statement
© The Author(s) 2024 Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.
License URL
Identifier
https://link.springer.com/article/10.1007/s00382-024-07196-0
Subjects
Air-sea interaction
Atmospheric blocking
CIRCULATION
Gulf stream
Jet stream
LATENT
Meteorology & Atmospheric Sciences
PACIFIC
Physical Sciences
POTENTIAL VORTICITY
Science & Technology
SURFACE TEMPERATURE ANOMALIES
THERMOCLINE
TRANSPORT
Publication Status
Published
Date Publish Online
2024-04-12