Results 61 to 70 of about 23,688 (213)

Elliptical Orbit Representation for the Annual Evolution of the Northern Hemisphere Stratospheric Polar Vortex. Part I: Diagnosing Interannual Variability

Journal of Geophysical Research: Atmospheres, Volume 131, Issue 5, 16 March 2026.
Abstract Using a single annual frequency with each year defined from July 1 to June 30 of the following calendar year, this study fits an ellipse to the yearly phase space trajectory of the daily time series of MU (stratospheric mass‐weighted zonally integrated zonal wind at 60°N) and M (total polar stratospheric air mass over 60–90°N) to represent the
Michael Secor, Jie Sun, Yueyue Yu, Zhaohua Wu, Ming Cai   +4 more
wiley   +1 more source

Role of the quasi-biennial oscillation in alleviating biases in the semi-annual oscillation [PDF]

Weather and Climate Dynamics
Model representations of the stratospheric semi-annual oscillation (SAO) show a common easterly bias, with a weaker westerly phase and stronger easterly phase compared to observations.
A. M. Jaison, A. M. Jaison, L. J. Gray, L. J. Gray, S. M. Osprey, S. M. Osprey, J. R. Knight, M. B. Andrews   +7 more
doaj   +1 more source

Quasi-Biennial Oscillation and Sudden Stratospheric Warmings during the Last Glacial Maximum

Atmosphere, 2020
The quasi-biennial oscillation (QBO) and sudden stratospheric warmings (SSWs) during the Last Glacial Maximum (LGM) are investigated in simulations using the Whole Atmosphere Community Climate Model version 6 (WACCM6).
Qiang Fu, Mingcheng Wang, Rachel H. White, Hamid A. Pahlavan, Becky Alexander, John M. Wallace   +5 more
doaj   +1 more source

Nonlinear Representation of the Quasi-Biennial Oscillation

Journal of the Atmospheric Sciences, 2009
AbstractA nonlinear principal component analysis (NLPCA) is applied to monthly mean zonal wind observations from January 1956 through December 2007 taken at seven pressure levels between 10 and 70 hPa in the stratosphere near the equator to represent the well-known quasi-biennial oscillation (QBO) and investigate its variability and structure.
Lionel Pandolfo, Bei-Wei Lu, Kevin Hamilton   +2 more
openaire   +1 more source

Elliptical Orbit Representation for the Annual Evolution of the Northern Hemisphere Stratospheric Polar Vortex. Part II: Long‐Lead Forecasts of Wintertime S2S Anomalies

Journal of Geophysical Research: Atmospheres, Volume 131, Issue 5, 16 March 2026.
Abstract In Part I, we represent the annual evolution of the Northern Hemisphere stratospheric polar vortex (SPV) in individual years using an ellipse, defined through six ellipse parameters, for the phase‐space trajectory of the daily time series of MU (mass‐weighted zonally integrated zonal wind at 60°N above 400 K) and M (stratospheric air mass over
Michael Secor, Jie Sun, Yueyue Yu, Zhaohua Wu, Ming Cai   +4 more
wiley   +1 more source

A Puzzling Quasi‐Periodic Variability in the Tropical Middle Atmosphere

Geophysical Research Letters
The Quasi‐Biennial Oscillation and the Semiannual Oscillation have been identified to be the leading modes of variability in the tropical middle atmosphere.
N. Koushik, K. Kishore Kumar
doaj   +1 more source

Quasi-biennial oscillation in GPS VTEC measurements

Advances in Space Research, 2014
Abstract The quasi-biennial oscillation, QBO, a well known periodicity in the equatorial stratospheric zonal winds, is also found in ionospheric parameters and in solar and geomagnetic activity indices. Many authors speculated about the link between the QBO in solar and geomagnetic activity and the QBO in atmospheric parameters.
Fernandez, Laura Isabel, Meza, Amalia Margarita, Elias, Ana Georgina   +2 more
openaire   +2 more sources

Beyond Geostrophic and Gradient Wind: Enhancing the Estimation of Climatic Wind Fields From Radio Occultation

Earth and Space Science, Volume 13, Issue 3, March 2026.
Abstract Wind approximations, such as geostrophic and gradient wind, are limited in their ability to accurately represent atmospheric conditions in the presence of significant planetary wave activity. Those approximations, while widely applied in synoptic‐scale wind field estimation, fail to capture the full complexity of atmospheric dynamics under ...
Johannes Unegg, I. Nimac, J. Danzer
wiley   +1 more source

An Idealized Two‐Dimensional Atmospheric Model of the Quasi‐Biennial Oscillation and Wave‐Mean Flow Interactions in the Equatorial Channel

Journal of Advances in Modeling Earth Systems, Volume 18, Issue 3, March 2026.
Abstract The quasi‐biennial oscillation (QBO) is a fundamental mode of atmospheric variability and a textbook example of wave‐mean flow interactions. While its general theory has been established about 50 years ago by the seminal works of Holton, Lindzen and Plumb (HLP), it remains an unsettled problem of geophysical fluid dynamics and a challenge for ...
Vincent Brémaud, Aurélien Podglajen, Albert Hertzog, Riwal Plougonven   +3 more
wiley   +1 more source

Cross-scale causal information flow from the El Niño–Southern Oscillation to precipitation in eastern China [PDF]

Earth System Dynamics
The El Niño–Southern Oscillation (ENSO) is a dominant mode of climate variability influencing temperature and precipitation in distant parts of the world. Traditionally, the ENSO influence is assessed considering its amplitude.
Y. Latif, K. Fan, K. Fan, G. Wang, M. Paluš   +4 more
doaj   +1 more source