Abstract Using potential vorticity to define Northern Hemisphere (NH) stratospheric polar vortex strength and position, the influence of QBO on in winter is analyzed. The results show that weakened/enhanced NH lower stratosphere during easterly/westerly (E/WQBO) phases more noticeable January February than November December. Furthermore, shows a shift toward Eurasian continent away from North America EQBO compared with WQBO phases, greater weaker impact zonal mean wind temperature found...

The Arctic has experienced several extreme springtime stratospheric ozone depletion events over the past four decades, particularly in 1997, 2011 and 2020. However, impact of this on climate system remains poorly understood. Here we show that causes significant reductions sea ice concentration (SIC) thickness (SIT) Kara Sea, Laptev Sea East Siberian from spring to summer. This is partially caused by enhanced transport Barents-Kara Fram Strait, which induced a strengthened longer lived polar...

Abstract Recent studies have suggested that deep Arctic warming, extending from the surface to upper troposphere, could trigger mid-latitude atmospheric circulation changes, while shallow confined in lowermost induces comparatively weak remote responses. The causes of mid-to-upper tropospheric warming are less clear compared with near-surface warming. Here, we demonstrate a new dynamical mechanism responsible for polar associated sea-ice loss, using both reanalysis and model simulations....

Abstract Using the European Centre for Medium-Range Weather Forecasts (ECMWF) interim reanalysis (ERA-Interim) dataset and Specified Chemistry Whole Atmosphere Community Climate Model (WACCM-SC), impacts of sea ice reduction in Barents–Kara Seas (BKS) on East Asian trough (EAT) late winter are investigated. Results from both data simulations show that BKS leads to a deepened EAT winter, especially February, while axis tilt is not sensitive reduction. Further analysis shows influences through...

Abstract Using ozone observations, reanalysis data, and climate model simulations, this study investigates in detail the independent joint influences of eastern Pacific (EP) El Niño–Southern Oscillation (ENSO) quasi‐biennial oscillation (QBO) on stratospheric Northern Hemisphere (NH) during winter. Statistically, NH winter increases Niño events but decreases La Niña events. Stratospheric east wind phases QBO (EQBO) west (WQBO). The anomalies middle high latitudes caused by ENSO activities...

Abstract The impact of Antarctic sea ice reduction during early austral winter on the stratospheric polar vortex is investigated using reanalysis data set and model simulations. Both simulations show that leads to a northward displacement tropospheric mid‐latitude jet, resembling negative phase Southern Annular Mode. Meanwhile, induces weaker winter, which accompanied by night jet. Further analysis indicates could lead greater excitation Rossby waves significant positive geopotential height...

Abstract This study explores the response of Arctic sea ice to CO 2 removal and its subsequent effects on winter Northern Hemisphere atmospheric circulation. Using multimodel ensembles from Carbon Dioxide Removal Model Intercomparison Project, we find that most models display incomplete sea‐ice recovery when is stabilized back at preindustrial levels, with a deficit area around 1 million km . associated residual equatorward‐shifted wintertime midlatitude jets. Sea‐ice perturbation...

This study explores the response of Arctic sea ice to CO2 removal and its subsequent effects on winter Northern Hemisphere atmospheric circulation. Using multimodel ensembles from Carbon Dioxide Removal Model Intercomparison Project, we find that most models display incomplete sea-ice recovery when CO2 is stabilized back at preindustrial levels, with a deficit area around 1 million km². is associated residual equatorward-shifted wintertime midlatitude jets. Sea-ice...

Abstract Using the NCEP–NCAR reanalysis dataset, this study classifies stratospheric northern annular mode (NAM) anomalies during negative or positive phase into two categories—anomalies extending troposphere [trop event (TE); referred to as TEs] and those not [nontrop (NTE); NTEs], corresponding tropospheric environments TEs NTEs are identified. Compared with that for NTEs, upward wave fluxes entering stratosphere stronger more persistent TEs. Furthermore, due favorable conditions...

Abstract Reduced Arctic sea‐ice has been proposed to induce severe Eurasian cold events. However, the physical mechanisms for this connection, particularly relative importance of tropospheric and stratospheric processes, remain unclear. Using ERA‐Interim reanalysis data WACCM‐SC simulations, we show that cooling induced by reduced centers over eastern Asia northern Europe. Tropospheric processes contribute roughly equally Asia, while contributions are 60% 40%, respectively, In pathway,...

Abstract Our study reframes our understanding of stratosphere–troposphere interactions, traditionally thought to be confined within individual hemispheres, by introducing a novel cross-hemispheric link. We demonstrate that strong boreal winter Arctic stratospheric polar vortex (APV) boosts the transmission upper tropospheric waves from Northern Hemisphere’s mid-high latitudes equator. Facilitated tropical central and eastern Pacific’s ‘westerly bridge’, these reach Southern latitudes. The...

Abstract Using reanalysis datasets and a coupled general circulation model, the relationship between springtime Arctic total column ozone (TCO) surface (5 m) ocean currents in North Pacific is investigated. We found that as March TCO decreases, statistically significant northwestward current anomaly occurs northern layer, but an anomalous southward appears central April, vice versa. The decreased favors enhanced stratospheric circulation, which tends to induce tropospheric positive...

Abstract We consider the combined and individual influences of Arctic sea-ice loss, sea surface temperature (SST) warming, direct radiative effect increased CO 2 on Northern Hemispheric climate. The climate (e.g., temperature, precipitation) atmospheric circulation responses level pressure, wind) to these drivers are quantified using simulations from Polar Amplification Model Intercomparison Project (for loss SST warming) Cloud Feedback ). verify linear additivity PAMIP-derived winter...

Abstract The stratosphere is a key link between El Niño and Eurasian surface climate in winter. Instead of the amplitude stratospheric response discussed by many previous studies, we focus on persistence wintertime extreme impacts through pathway to midlatitude Eurasia spring. A novel approach used running WACCM4 with forcing imposed only during winter isolate role following We show that descending signal strong deceleration zonal wind throughout atmosphere could reach persist spring events,...

Abstract Using the ERA-Interim reanalysis dataset for time period 1979–2016, we analyzed influence of stratospheric polar vortex shift on Arctic Oscillation (AO) in winter (December–March). The results show that a toward Eurasian continent is favorable occurrence negative phase AO. duration AO events accompanied by (AO-shift events) longer than remaining (AO-noshift events), and intensity AO-shift greater AO-noshift from day 4 to 15 life cycle events. enhancement during likely due downward...

Abstract Impacts of stratospheric polar vortex shift on the wintertime East Asian trough (EAT) intraseasonal time scales are investigated using a reanalysis dataset and climate model. The result based composite analysis shows that toward eastern Siberia (ES-shift event) is associated with higher geopotential height at 500 hPa than normal over Asia, corresponding to weakened EAT. Furthermore, simulated EAT also when nudging state during ES-shift events. This study further found there no...

Abstract Using a large ensemble of simulations from the Polar Amplification Model Intercomparison Project (PAMIP) and phase 6 Coupled (CMIP6), we compare response winter-mean precipitation daily extremes across Northern Hemisphere to future Arctic sea ice loss global ocean warming. The North Atlantic is simulated become drier in loss, with reduced intensity more dry days. A wetting over midlatitude Ocean. These responses are robust eight models analyzed, albeit differences their magnitude...

Abstract Based on multi‐model large‐ensemble experiments provided by Polar Amplification Model Intercomparison Project (PAMIP), we investigate the influence of projected sea ice loss in Barents‐Kara Seas (BKS) and Sea Okhotsk (SOK) Arctic stratospheric polar vortex (SPV). Results show that future BKS reduction leads to a weakened SPV during November‐February enhancing upward‐propagating planetary wave 1, which is more pronounced Quasi‐Biennial Oscillation (QBO) easterly than westerly phase....

The effects of wintertime stratospheric polar vortex variation on the climate over North Pacific Ocean during late winter and spring are analyzed using National Centers for Environmental Predictions, version 2 (NCEP2) reanalysis dataset. analysis revealed that, weak (WPV) events, there noticeably lower geopotential height anomalies Bering Sea greater central part than strong (SPV) events. formation dipolar structure is due to a weakened jet strengthened mid-latitude in troposphere via...

Abstract. Using multiple reanalysis datasets and modeling simulations, the trends of Antarctic stratospheric planetary wave activities in early austral spring since 2000s are investigated this study. We find that September have weakened significantly year 2000, which is mainly related to weakening tropospheric sources extratropical Southern Hemisphere. As ozone also shows clear shift around impact recovery on activity examined through numerical simulations. Significant lower stratosphere...