Results 61 to 70 of about 320 (144)
Climatic Higher‐Order Balanced Winds Beyond Geostrophic and Gradient Wind Fields
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
We examine the zonal wavenumber spectrum of planetary (Rossby) waves in the atmosphere above Antarctica in each of two contrasting years: in 2019, when there was a sudden stratospheric warming (SSW), and in 2020 when the Antarctic stratospheric vortex ...
A. Grytsai +5 more
doaj +1 more source
Abstract. Stratospheric Sudden Warmings (SSWs) significantly affect surface climate in boreal winter. However, their impacts vary considerably from one event to another: more than one-third of SSWs are not followed by expected tropospheric anomalies. To isolate the forced responses to SSWs, this study analyzes model experiments from the Stratospheric ...
Dong-Chan Hong +7 more
openaire +2 more sources
Drivers of Mid‐Latitude Quiet‐Time Longitude Variations in Ionospheric Density
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 +3 more
wiley +1 more source
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 +5 more
wiley +1 more source
The ability to predict climate fluctuations at seasonal timescales offers significant socio‐economic benefits. However, limited understanding of predictability mechanisms and model errors hinders forecast quality. Recent research has improved forecasting systems and data quality.
Silvio Gualdi +12 more
wiley +1 more source
Windows of opportunity in subseasonal weather regime forecasting: A statistical–dynamical approach
This study explores how the atmospheric state at initialisation creates windows of opportunity for improving week 3 forecasts of weather regime activity. Greenland blocking activity increases following Madden–Julian Oscillation phases 7, 8, and 1 and weak stratospheric polar vortex states, revealing patterns exploitable by statistical models.
Fabian Mockert +3 more
wiley +1 more source
The response of the thermospheric daytime longitudinally averaged zonal and meridional winds and neutral temperature to the 2020/2021 major sudden stratospheric warming (SSW) is studied at low-to middle latitudes (0◦ - 40◦N) using observations by NASA’s ...
Erdal Yiğit +6 more
doaj +1 more source
Assessing the impact of model biases on subseasonal forecast skill
Relaxation experiments where the nudging was performed towards bias‐corrected integrations of the same model display significantly improved skill at weeks 3 and 4, particularly in the northern extratropics. This indicates that there is a large potential for improving dynamical subseasonal forecasting skill by improved treatment of model biases.
Frédéric Vitart, Magdalena Balmaseda
wiley +1 more source
Satellite Reentry Predictions During Sudden Stratospheric Warmings
Abstract Prediction of uncontrolled satellite reentry time and trajectory are essential to avoid damages to human being and properties over land. Reentry time and trajectory are largely controlled by aerodynamic drag and mass neutral density below 200 km.
Jia Yue +6 more
wiley +1 more source

