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  1. Links Section In This Post, below the intro. I have been recently asked to start a thread, to talk about weather teleconnections and similar topics. This is often a topic not very well discussed on other weather places, and places like Twitter. We have a number of experts, enthusiasts, and meteorologists, who are knowledgeable in this area. So this is a thread for technical discussion about the teleconnections, etc, as well as a place for questions about these topics. We need to start talking about these climate drivers more, as they are the key to unlocking medium-long term forec
  2. Propagating Annular Modes: Empirical Orthogonal Functions, Principal Oscillation Patterns, and Time Scales Authors: Aditi Sheshadri and R. Alan Plumb Published online: 10th April, 2017 Abstract: The two leading empirical orthogonal functions (EOFs) of zonal-mean zonal wind describe north–south fluctuations, and intensification and narrowing, respectively, of the midlatitude jet. Under certain circumstances, these two leading EOFs cannot be regarded as independent but are in fact manifestations of a single, coupled, underlying mode of the dynamical sys
  3. The Effect of Tropospheric Jet Latitude on Coupling between the Stratospheric Polar Vortex and the Troposphere Authors: Chaim I. Garfinkel, Darryn W. Waugh and Edwin P. Gerber Published online: 22nd March, 2013 Abstract: A dry general circulation model is used to investigate how coupling between the stratospheric polar vortex and the extratropical tropospheric circulation depends on the latitude of the tropospheric jet. The tropospheric response to an identical stratospheric vortex configuration is shown to be strongest for a jet centered near 40° an
  4. A mechanism for lagged North Atlantic climate response to solar variability Authors: Adam A. Scaife, Sarah Ineson, Jeff R. Knight, Lesley Gray, Kunihiko Kodera and Doug M. Smith First Published: 3rd January, 2013 Abstract: Variability in solar irradiance has been connected to changes in surface climate in the North Atlantic through both observational and climate modelling studies which suggest a response in the atmospheric circulation that resembles the North Atlantic Oscillation or its hemispheric equivalent the Arctic Oscillation. It has also
  5. Solar forcing of winter climate variability in the Northern Hemisphere Authors: Sarah Ineson, Adam A. Scaife, Jeff R. Knight, James C. Manners, Nick J. Dunstone, Lesley J. Gray and Joanna D. Haigh First Published: 9th October, 2011 Abstract: An influence of solar irradiance variations on Earth’s surface climate has been repeatedly suggested, based on correlations between solar variability and meteorological variables. Specifically, weaker westerly winds have been observed in winters with a less active sun, for example at the minimum phase
  6. Observed and Simulated Teleconnections Between the Stratospheric Quasi‐Biennial Oscillation and Northern Hemisphere Winter Atmospheric Circulation Authors: Martin B. Andrews , Jeff R. Knight, Adam A. Scaife, Yixiong Lu, Tongwen Wu, Lesley J. Gray and Verena Schenzinger Published: 15th January, 2019 Abstract: The Quasi‐Biennial Oscillation (QBO) is the dominant mode of interannual variability in the tropical stratosphere, with easterly and westerly zonal wind regimes alternating over a period of about 28 months. It appears to influence the Northern
  7. Enhanced Stratosphere/Troposphere Coupling During Extreme Warm Stratospheric Events with Strong Polar-Night Jet Oscillation Author: Dieter H.W. Peter, Andrea Schneidereit and Alexey Y. Karpechko Published: November 29th, 2018 Abstract: Extreme warm stratospheric events during polar winters from ERA-Interim reanalysis and CMIP5-ESM-LR runs were separated by duration and strength of the polar-night jet oscillation (PJO) using a high statistical confidence level of three standard deviations (strong-PJO events). With a composite analysis, we demo
  8. Eurasian snow cover variability and links to winter climate in the CMIP5 models Author: Jason C. Furtado, Judah L. Cohen, Amy H. Butler, Emily E. Riddle and Arun Kumar Published: 31st January, 2015 Abstract: Observational studies and modeling experiments illustrate that variability in October Eurasian snow cover extent impacts boreal wintertime conditions over the Northern Hemisphere (NH) through a dynamical pathway involving the stratosphere and changes in the surface-based Arctic Oscillation (AO). In this paper, we conduct a comprehensive study
  9. How Predictable Are the Arctic and North Atlantic Oscillations? Exploring the Variability and Predictability of the Northern Hemisphere Authors: Daniela I. V. Domeisena, Gualtiero Badin and Inga M. Koszalka Published: 18th January, 2018 Abstract: The North Atlantic Oscillation (NAO) and the Arctic Oscillation (AO) describe the dominant part of the variability in the Northern Hemisphere extratropical troposphere. Because of the strong connection of these patterns with surface climate, recent years have shown an increased interest and an increasing s
  10. Northern Hemisphere Stratospheric Pathway of Different El Niño Flavors in Stratosphere-Resolving CMIP5 Models Authors: N. Calvo, M. Iza, M. M. Hurwitz, E. Manzini, C. Peña-Ortiz, A. H. Butler, C. Cagnazzo, S. Ineson and C. I. Garfinkel Published: 10th May, 2017 Abstract: The Northern Hemisphere (NH) stratospheric signals of eastern Pacific (EP) and central Pacific (CP) El Niño events are investigated in stratosphere-resolving historical simulations from phase 5 of the Coupled Model Intercomparison Project (CMIP5), together with the role of th
  11. Impact of the Stratosphere on the Winter Tropospheric Teleconnections between ENSO and the North Atlantic and European Region Authors: Chiara Cagnazzor and Elisa Manzini Published: 21st August, 2008 Abstract: The possible role of stratospheric variability on the tropospheric teleconnection between El Niño–Southern Oscillation (ENSO) and the North Atlantic and European (NAE) region is addressed by comparing results from two ensembles of simulations performed with an atmosphere general circulation model fully resolving the stratosphere (with the top a
  12. Linking stratospheric circulation extremes and minimum Arctic sea ice extent Workshop Presentation: Aspen Global Change Institute, Aspen, Colorado Workshop Programme: “Understanding the Causes and Consequences of Polar Amplification” - June 12th -16th, 2017 Presenter: Karen Smith, Lorenzo Polvani and Bruno Tremblay Presentation Date: 14th June, 2017 Link to full presentation (32 minute video): https://www.agci.org/lib/17s1/linking-stratospheric-circulation-extremes-and-minimum-arctic-sea-ice-extent Link t
  13. Snow–(N)AO Teleconnection and Its Modulation by the Quasi-Biennial Oscillation Authors: Y. Peings Published: 29th November, 2017 Abstract: This study explores the wintertime extratropical atmospheric response to Siberian snow anomalies in fall, using observations and two distinct atmospheric general circulation models. The role of the quasi-biennial oscillation (QBO) in modulating this response is discussed by differentiating easterly and westerly QBO years. The remote influence of Siberian snow anomalies is found to be weak in the models,
  14. The Role of Zonal Asymmetry in the Enhancement and Suppression of Sudden Stratospheric Warming Variability by the MJO Authors: Wanying Kang and Eli Tziperman Published: 20th February, 2018 Abstract: Sudden stratospheric warming (SSW) events influence the Arctic Oscillation and midlatitude extreme weather. Previous work showed the Arctic stratosphere to be influenced by the Madden–Julian oscillation (MJO) and that the SSW frequency increases with an increase of the MJO amplitude, expected in a warmer climate. It is shown here that the zonal
  15. Upward Wave Activity Flux as a Precursor to Extreme Stratospheric Events and Subsequent Anomalous Surface Weather Regimes Authors: Lorenzo M. Polvani and Darryn W. Waugh Published: 12th January, 2004 Abstract: It has recently been shown that extreme stratospheric events (ESEs) are followed by surface weather anomalies (for up to 60 days), suggesting that stratospheric variability might be used to extend weather prediction beyond current time scales. In this paper, attention is drawn away from the stratosphere to demonstrate that the originatin
  16. Time-Lagged Response of the Antarctic and High-Latitude Atmosphere to Tropical MJO Convection Authors: Gina R. Henderson, Bradford S. Barrett, Ashley Lois, and Haadi Elsaawy Published: 22nd February, 2018 (online: 18th April, 2018) Abstract: Intraseasonal tropical variability has important implications for the mid- and high-latitude atmosphere, and in recent studies has been shown to modulate a number of weather processes in the Northern Hemisphere, such as snow depth, sea ice concentration, precipitation, atmospheric rivers, and air temperature. In
  17. Atmospheric summer teleconnections and Greenland Ice Sheet surface mass variations: insights from MERRA-2 Authors: Young-Kwon Lim, Siegfried D Schubert, Sophie M J Nowicki, Jae N Lee, Andrea M Molod, Richard I Cullather, Bin Zhao and Isabella Velicogna Published: 1st February, 2016 (IOP Publishing Ltd) Abstract: The relationship between leading atmospheric teleconnection patterns and Greenland Ice Sheet (GrIS) temperature, precipitation, and surface mass balance (SMB) are investigated for the last 36 summers (1979–2014) based on Modern-Era Retrospect
  18. Effects of Arctic Sea Ice Decline on Weather and Climate: A Review Authors: Timo Vihma Published: 9th March, 2014 Abstract: The areal extent, concentration and thickness of sea ice in the Arctic Ocean and adjacent seas have strongly decreased during the recent decades, but cold, snow-rich winters have been common over mid-latitude land areas since 2005. A review is presented on studies addressing the local and remote effects of the sea ice decline on weather and climate. It is evident that the reduction in sea ice cover has increased the heat flux from t
  19. Increased Variability in the Early Winter Subarctic North American Atmospheric Circulation Authors: James E. Overland (NOAA)and Muyin Wang (Joint Institute for the Study of the Atmosphere and Ocean, University of Washington) Published: 23rd July, 2015 (published online: 11th September, 2015) Abstract: The last decade shows increased variability in the Arctic Oscillation (AO) index for December. Over eastern North America such increased variability depended on amplification of the climatological longwave atmospheric circulation pattern. Re
  20. Arctic Oscillation (AO) - A Simple Guide Authors: NOAA Published: Current - updated monthly Summary: This is another one of the excellent NOAA guides with a simple definition. There is a table showing the monthly values of the AO from 1950 right up to the most recent month. There is also a chart showing these values from 1950 to 2011. Link to Web Page: https://www.ncdc.noaa.gov/teleconnections/ao/
  21. On the atmospheric response experiment to a Blue Arctic Ocean: Climate Response to Blue Arctic Ocean Authors: Nakamura, Yamazaki, Honda, Dethloff. Published: Sept 2016 Abstract: Arctic warming is among the most remarkable of climate change signals undergoing global warming, and has resulted in continuous changes to the Arctic environment. Arctic sea ice loss is one of the most symbolic signatures of these rapid climate changes. Changes to Arctic sea ice are crucial to the coupled climate system, because ice melting is stimulated by atmospheric a
  22. Changes in meandering of the Northern Hemisphere circulation Authors: Giorgia Di Capua and Dim Coumou Published: 22nd September, 2016 (© 2016 IOP Publishing Ltd) Abstract: Strong waves in the mid-latitude circulation have been linked to extreme surface weather and thus changes in waviness could have serious consequences for society. Several theories have been proposed which could alter waviness, including tropical sea surface temperature anomalies or rapid climate change in the Arctic. However, so far it remains unclear whether any changes in wav
  23. Evidence linking Arctic amplification to extreme weather in mid-latitudes Received 17 January 2012; revised 20 February 2012; accepted 21 February 2012; published 17 March 2012 Authors: Jennifer A. Francis and Stephen J. Vavrus First Published: 17th January, 2012 (revised 20th February 2012; published online 17th March, 2012) Abstract: Arctic amplification (AA) – the observed enhanced warming in high northern latitudes relative to the northern hemisphere – is evident in lower‐tropospheric temperatures and in 1000‐to‐500 hPa thickn
  24. Evidence for a wavier jet stream in response to rapid Arctic warming Authors: Jennifer A Francis and Stephen J Vavrus Published: 6th January, 2015 (© 2015 IOP Publishing Ltd) Abstract: New metrics and evidence are presented that support a linkage between rapid Arctic warming, relative to Northern hemisphere mid-latitudes, and more frequent high-amplitude (wavy) jet-stream configurations that favor persistent weather patterns. We find robust relationships among seasonal and regional patterns of weaker poleward thickness gradients, weaker zona
  25. Mountain Torques and Northern Hemisphere Low-Frequency Variability.Part II: Regional Aspects Authors: Francois Lott, Andrew W. Robertson and Michael Ghil First Published: 16th November 2001 (published online: 1st June , 2004) Abstract: Important aspects of low-frequency variability (LFV) are regional in character, while the mountain torques of the Rockies and the Himalayas evolve quite independently of each other. The hemispheric analysis of Part I is complemented therefore herein by an analysis of the relationships between individual mountain to
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