Results 61 to 70 of about 1,935 (190)

Stratospheric sudden warmings in an idealized GCM [PDF]

, 2016
PublishedJournal ArticleAn idealized general circulation model (GCM) with an analytically described Newtonian cooling term is employed to study the occurrence rate of sudden stratospheric warmings (SSWs) over a wide range of parameters.
Fueglistaler, S, Jucker, M, Vallis, Geoffrey K.   +2 more
core   +1 more source

Climatic Higher‐Order Balanced Winds Beyond Geostrophic and Gradient Wind Fields

Earth and Space Science, Volume 13, Issue 5, May 2026.
Abstract We present a novel approach to derive three‐dimensional Climatic Higher‐Order Balanced (CHOB) wind fields from thermodynamic state variables in the free troposphere and stratosphere. The CHOB method is developed for monthly synoptic‐scale wind field estimation, utilizing commonly used balanced winds (geostrophic and gradient wind) enhanced by ...
I. Nimac, J. Unegg, J. Danzer
wiley   +1 more source

Extracting gravity wave parameters during the September 2002 Southern Hemisphere major sudden stratospheric warming using a SANAE imaging riometer [PDF]

, 2013
Using absorption data measured by imaging riometer for ionospheric studies (IRIS) located at the South Africa National Antarctic Expedition (SANAE), Antarctica (72° S, 3° W), we extracted the parameters of gravity waves (GW) of periods between 40 and ...
H. Bencherif, N. Mbatha, N. Mbatha, S. Malinga, V. Sivakumar   +4 more
core   +2 more sources

Drivers of Mid‐Latitude Quiet‐Time Longitude Variations in Ionospheric Density

Journal of Geophysical Research: Space Physics, Volume 131, Issue 5, May 2026.
Abstract The aim of this study is to provide an observational benchmark of mid‐latitude quiet‐time variability in winds, O/N2, and TEC across longitude and local time to provide a foundation for future model–data comparison studies. The quiet‐time ionospheric structure is not uniform but rather exhibits pronounced longitudinal and local‐time ...
K. R. Greer, L. P. Goncharenko, V. L. Harvey, C. Cullens   +3 more
wiley   +1 more source

VARIABILITY OF IONOSPHERIC F2 REGION DUE TO SUDDEN STRATOSPHERIC WARMING EVENT OF 2017 [PDF]

Proceedings on Engineering Sciences
We analyzed the impact of minor Arctic sudden stratospheric warming (SSW) event of 2017 on the ionospheric F2 region, using Digisonde data from a low-mid latitude Indian station, Delhi (28.6°N, 77.2°E, 19.2°N geomagnetic latitude, 42.4°N dip).
Qadeer Ahmed, Anshul Singh , N. Praneetha , Ankit Gupta , Arti Bhardwaj , Puja Goel , Arun Kumar Upadhayaya   +6 more
doaj   +1 more source

Stratosphere-troposphere evolution during polar vortex intensification [PDF]

, 2005
Stratosphere-troposphere evolution associated with polar vortex intensification (VI) events is examined during the Northern Hemisphere winter. The incipient stage of a VI event is marked by anomalously low wave activity and descending westerly anomalies ...
Hartmann, Dennis L., Jeev, Kumar, Limpasuvan, Varavut, Thompson, David W. J., Yung, Yuk L.   +4 more
core   +1 more source

Decadal Changes in Wintertime Frequency of Stratospheric Northern Annular Mode Events With Downward Propagation

Geophysical Research Letters, Volume 53, Issue 8, 28 April 2026.
Abstract The surface climate impact of stratospheric polar vortex anomalies depends on their downward propagation (DP) into the troposphere. We find pronounced decadal variability in the winter frequency of stratospheric Northern Annular Mode (SNAM) events that exhibit DP (1951–2024).
Yang Liu, Yueyue Yu, Ming Cai, Rongcai Ren, Lijuan Chen, Donghan Wang   +5 more
wiley   +1 more source

Variabilities of mesospheric tides and equatorial electrojet strength during major stratospheric warming events [PDF]

, 2009
The present study demonstrates the relationship between the high latitude northern hemispheric major sudden stratospheric warming (SSW) events and the reversal in the afternoon equatorial electrojet (EEJ), often called the counter-electrojet (CEJ ...
S. Gurubaran, S. Sathishkumar, S. Sridharan   +2 more
core   +7 more sources

Enhanced Polar Vortex Predictability Following Sudden Stratospheric Warming Events

Geophysical Research Letters, 2023
Sudden stratospheric warming (SSW) events can form a window of forecast opportunity for polar vortex predictions on subseasonal‐to‐seasonal time scales.
Philip Rupp, Jonas Spaeth, Hella Garny, Thomas Birner   +3 more
doaj   +1 more source

Observational Evidence of Distinguishable Weather Patterns for Three Types of Sudden Stratospheric Warming During Northern Winter

Frontiers in Earth Science, 2021
Sudden stratospheric warming (SSW) events often lead to a cold surface air temperature anomaly over the extratropical regions. In this study, we propose, through observational evidence, that the types of SSW determine the severity of the cold anomaly ...
Hyesun Choi, Joo-Hong Kim, Baek-Min Kim, Seong-Joong Kim   +3 more
doaj   +1 more source