Results 11 to 20 of about 1,013 (182)

Forecasting extreme stratospheric polar vortex events. [PDF]

Nat Commun, 2020
AbstractExtreme polar vortex events known as sudden stratospheric warmings can influence surface winter weather conditions, but their timing is difficult to predict. Here, we examine factors that influence their occurrence, with a focus on their timing and vertical extent. We consider the roles of the troposphere and equatorial stratosphere separately,
Gray LJ, Brown MJ, Knight J, Andrews M, Lu H, O'Reilly C, Anstey J.   +6 more
europepmc   +6 more sources

Diverse Surface Signatures of Stratospheric Polar Vortex Anomalies [PDF]

Journal of Geophysical Research: Atmospheres, 2022
Abstract The Arctic stratospheric polar vortex is an important driver of winter weather and climate variability and predictability in North America and Eurasia, with a downward influence that on average projects onto the North Atlantic Oscillation (NAO).
E. W. Kolstad, S. H. Lee, A. H. Butler, D. I. V. Domeisen, C. O. Wulff   +4 more
openaire   +6 more sources

Cyclone‐Like Features Within the Stratospheric Polar‐Night Vortex

Geophysical Research Letters
Distinctive synoptic‐scale (∼1,500 km) flow features are identified within the core of the stratospheric polar‐night vortex at stratopause altitudes (∼50 km).
Huw C. Davies, Michael Sprenger
doaj   +3 more sources

Hyperbolic lines and the stratospheric polar vortex [PDF]

Chaos: An Interdisciplinary Journal of Nonlinear Science, 2002
The necessary and sufficient conditions for Lagrangian hyperbolicity recently derived in the literature are reviewed in the light of older concepts of effective local rotation in strain coordinates. In particular, we introduce the simple interpretation of the necessary condition as a constraint on the local angular displacement in strain coordinates ...
Koh, T.-Y., Legras, B.
openaire   +4 more sources

Stratospheric downward wave reflection events modulate North American weather regimes and cold spells [PDF]

Weather and Climate Dynamics, 2022
The Arctic stratospheric polar vortex is an important driver of mid-latitude winter cold spells. One proposed coupling mechanism between the stratospheric polar vortex and the troposphere is upward-propagating planetary waves being reflected downward by ...
G. Messori, G. Messori, G. Messori, G. Messori, M. Kretschmer, S. H. Lee, V. Wendt, V. Wendt   +7 more
doaj   +1 more source

Adding value to extended-range forecasts in northern Europe by statistical post-processing using stratospheric observations [PDF]

Atmospheric Chemistry and Physics, 2020
The strength of the stratospheric polar vortex influences the surface weather in the Northern Hemisphere in winter; a weaker (stronger) than average stratospheric polar vortex is connected to negative (positive) Arctic Oscillation (AO) and colder (warmer)
N. Korhonen, O. Hyvärinen, M. Kämäräinen, D. S. Richardson, H. Järvinen, H. Gregow   +5 more
doaj   +1 more source

The Delayed Response of the Troposphere‐Stratosphere‐Mesosphere Coupling to the 2019 Southern SSW

Geophysical Research Letters, 2022
A strong Southern Hemisphere (SH) sudden stratospheric warming event occurred in September 2019 and significantly weakened the stratospheric polar vortex. Due to the positive zonal wind anomalies in the troposphere, the barotropic/baroclinic instability,
Chengyun Yang, Tao Li, Dexin Lai, Xinyue Wang, Xianghui Xue, Xiankang Dou   +5 more
doaj   +1 more source

Pathways of Influence Between Northern Hemisphere Blocking and Stratospheric Polar Vortex Variability

Geophysical Research Letters, 2022
We apply a causal inference‐based framework to test and quantify previously suggested causal relationships between Northern Hemisphere blocking, upward wave‐activity fluxes and stratospheric polar vortex (SPV) variability using reanalysis data.
Kamilya Yessimbet, Theodore G. Shepherd, Albert C. Ossó, Andrea K. Steiner   +3 more
doaj   +1 more source

Arctic Stratosphere Dynamical Processes in the Winter 2021–2022

Atmosphere, 2022
The Arctic stratosphere winter season of 2021–2022 was characterized by a stable, cold stratospheric polar vortex with a volume of polar stratospheric clouds (PSC) close to the maximum values since 1980, before the beginning of minor sudden stratospheric
Pavel N. Vargin, Andrey V. Koval, Vladimir V. Guryanov   +2 more
doaj   +1 more source

The stratospheric polar vortex and sudden stratospheric warmings [PDF]

Weather, 2020
The polar vortex is the dominant feature of the wintertime stratosphere. Sometimes, it is unusually strong, while at others it is very weak or destroyed in an event known as a sudden stratospheric warming (SSW). Both can play an important role in driving the type and predictability of the weather we experience at the surface.
openaire   +1 more source