Introducing The New WUWT Northern Polar Vortex Page – With Explanation and Observations

NASA – Goddard Space Flight Center – Arctic Ozone Watch – Click the pic to view at source

By WUWT Regular “Just The Facts”

We are pleased to introduce WUWT’s newest addition, the WUWT Northern Polar Vortex Reference Page. We would like to dedicate this page to NBC News and John Holdren, who both seem to need all the help they can get in understanding Polar Vorticity.

“The stratospheric polar vortex is a large-scale region of air that is contained by a strong west-to-east jet stream that circles the polar region. This jet stream is usually referred to as the polar night jet. The polar vortex extends from the tropopause (the dividing line between the stratosphere and troposphere) through the stratosphere and into the mesosphere (above 50 km). Low values of ozone and cold temperatures are associated with the air inside the vortex.” NASA

“Polar vortices are ubiquitous atmospheric structures. In the Solar System, Earth, Mars, Venus, (Jupiter ), Saturn and its moon Titan are known to have well developed vortices in their polar regions at high altitude. These swirling structures are not always present in the atmosphere of a planetary body at all seasons, but they generally form in the winter hemisphere, when the latitudinal equator-to-pole temperature gradients are the strongest. For Earth, Mars, Saturn and Titan, therefore, the axial tilt determines the presence and seasonal variability of their polar vortices. This can be observed, for instance, by looking at the seasonality of the maximum speed of the circumpolar jets (see [6] for examples related to the Earth and Mars). Venus has a negligible axial tilt; therefore one would expect that the seasonality of its polar vortices is absent. Nonetheless, their seasonality seems to be induced by a dynamical phenomenon, linked to the presence of a quasi-bidiurnal oscillation at mid-latitudes, and extending to high latitudes, rather than by the obliquity of its rotation axis. This oscillation is observed in numerical simulations with global climate models, although its signature depends on the model as well as on model initialisation. A quasi-bidiurnal signal seems also to be present in some analysis of spacecraft data from Venus Express (see for instance [1]), although it has still to be understood whether its nature and origin are common to the oscillation observed in numerical simulations.” European Planetary Science Congress (Links and Jupiter added within)

Polar Vortices are “caused when an area of low pressure sits at the rotation pole of a planet. This causes air to spiral down from higher in the atmosphere, like water going down a drain.” Universe Today

“Long-term vortices are a frequent phenomenon in the atmospheres of fast rotating planets, like Jupiter and Saturn, for example. Venus rotates slowly, yet it has permanent vortices in its atmosphere at both poles. What is more, the rotation speed of the atmosphere is much greater than that of the planet. “We’ve known for a long time that the atmosphere of Venus rotates 60 times faster than the planet itself, but we didn’t know why. The difference is huge; that is why it’s called super-rotation. And we’ve no idea how it started or how it keeps going.

“The permanence of the Venus vortices contrasts with the case of the Earth. “On the Earth there are seasonal effects and temperature differences between the continental zones and the oceans that create suitable conditions for the formation and dispersal of polar vortices. On Venus there are no oceans or seasons, and so the polar atmosphere behaves very differently,” says Garate-Lopez.” Phys.org

“The stratospheric polar vortex shows quite a bit of day-to-day variability. This variability is caused by weather systems or large-scale waves that move upward from the troposphere into the stratosphere. In the left image (9 January 2010), we see some undulations along the edge of the polar vortex, but the vortex is generally centered on the North Pole. Two weeks later (center image on 23 January 2010) we see the center of the polar vortex pushed away from the North Pole. On a constant latitude circle, PV values are high in the eastern hemisphere and low in the western hemisphere. This is referred to as a wave-1 pattern (a wave-2 pattern can be seen in the vortex breakup section below). The wave-1 pattern develops in the troposphere and moves upward (propagates) into the stratosphere.

NASA – Goddard Space Flight Center – Arctic Ozone Watch – Click the pic to view at source

These stratospheric waves are forced by the large-scale mountain systems and the land-sea contrasts between the continents and oceans. During the northern winter, these waves are continuously forming and moving upward into the stratosphere. The waves can “break”, much like the waves on a beach. These wave-breaking events erode the vortex and keep the polar region warmer and ozone amounts higher. Often, parts of the polar vortex are pulled away from the main vortex. The image on the right (28 January 2010) shows this, where a large piece of the polar vortex was pulled away from the main vortex (green colored material at the bottom of the image). A comparison between the middle and right images also shows a slight contraction of the polar vortex because of these waves.”

“The polar vortex is a winter phenomena. It develops as the sun sets over the polar region and temperatures cool. During the spring, the sun rises and the absorption of solar radiation by ozone begins to heat the polar stratosphere. This heating eventually causes the vortex to disappear along with the polar night jet. However, this process is helped along by planetary-scale waves that propagate up from the troposphere. This wave event that drives the vortex breakup (or final warming) acts to also increase the temperature of the polar region and ozone levels. We mark the day of the vortex breakup when the winds around the vortex edge decrease below a particular value (about 15 m s -1on the 460 K potential temperature surface).”NASA

NASA – Goddard Space Flight Center – Arctic Ozone Watch – Click the pic to view at source

WUWT Northern Polar Vortex Reference Page offers focused view on the Northern Polar Vortex, whereas the WUWT Polar Vortex Reference Page offers a more broad overview of Global, Northern and Southern Polar Vorticity. When time permits, there will also be a WUWT Southern Polar Vortex Reference Page forthcoming. The following are some observation on recent Northern Polar Vortex activity from the WUWT Polar Vortex Reference Page:

Northern Hemisphere Temperature Analysis at 10 hPa/mb – Approximately 31,000 meters (101,700 feet) shows a high level split within the Stratospheric Polar Vortex on January 11th, 2014:

NOAA – National Weather Service – Climate Prediction Center – Click the pic to view at source

The split is also visible in Ozone Mixing Ratios at 30 hPa/mb – Approximately 23,700 meters (77,800 feet);

NOAA – National Weather Service – Climate Prediction Center – Click the pic to view at source

50 hPa/mb Height Analysis at Approximately 20,100 meters (66,000 feet):

NOAA – National Weather Service – Climate Prediction Center – Click the pic to view at source

70 hPa/mb Height Analysis – Approximately 18,000 meters (59,000 feet);

NOAA – National Weather Service – Climate Prediction Center – Click the pic to view at source

and 100 hPa/mb Height Analysis – Approximately 15,000 meters (49,000 feet):

NOAA – National Weather Service – Climate Prediction Center – Click the pic to view at source

Northern Hemisphere Area Where Temperature is Below 195K or -78C shows significant warming in the last few days;

NOAA – National Weather Service – Climate Prediction Center – Click the pic to view at source

The Vertical Cross Section of Geopotential Height Anomalies shows that the Polar Vortex has weakened significantly and the Arctic Oscillation swung to negative:

NOAA – National Weather Service – Climate Prediction Center – Click the pic to view at source

“The Arctic Oscillation refers to an opposing pattern of pressure between the Arctic and the northern middle latitudes. Overall, if the atmospheric pressure is high in the Arctic, it tends to be low in the northern middle latitudes, such as northern Europe and North America. If atmospheric pressure is low in the middle latitudes it is often high in the Arctic. When pressure is high in the Arctic and low in mid-latitudes, the Arctic Oscillation is in its negative phase. In the positive phase, the pattern is reversed.

Meteorologists and climatologists who study the Arctic pay attention to the Arctic Oscillation, because its phase has an important effect on weather in northern locations. The positive phase of the Arctic Oscillation brings ocean storms farther north, making the weather wetter in Alaska, Scotland, and Scandinavia and drier in the western United States and the Mediterranean. The positive phase also keeps weather warmer than normal in the eastern United States, but makes Greenland colder than normal.

In the negative phase of the Arctic Oscillation the patterns are reversed. A strongly negative phase of the Arctic Oscillation brings warm weather to high latitudes, and cold, stormy weather to the more temperate regions where people live.” NSIDC

NOAA – National Weather Service – Climate Prediction Center – Click the pic to view at source

In terms of why the Polar Vortex weakened and split, and the Atlantic Oscillation swung negative, there are likely several factors. the first being Planetary Waves, i.e. “The polar stratosphere and mesosphere are dynamically altered throughout the winter months by planetary wave activity and its interaction with the mean flow. An extreme interaction leads to polar vortex breakdown and a complete alteration in temperature from the lower stratosphere through the upper atmosphere. However, there are more regular disturbances where the dynamical interactions can alter the upper stratosphere and mesosphere without modification to the lower stratosphere; here these disturbances will be designated as Upper Stratospheric Lower Mesospheric (USLM) disturbances.” American Geophysical Union, Greer et al.

“The polar winter middle atmosphere is a dynamically active region that is driven primarily by wave activity. Planetary waves intermittently disturbed the region at different levels and the most spectacular type of disturbance is a major Sudden Stratospheric Warming (SSW). However, other types of extreme disturbances occur on a more frequent, intraseasonal basis. One such disturbances are synoptic-scale “weather events” observed in lidar and rocket soundings, soundings from the TIMED/SABER instrument and UK Meteorological Office (MetO) assimilated data. These disturbances are most easily identified near 42 km where temperatures are elevated over baseline conditions by a remarkable 50 K and an associated cooling is observed near 75 km. As these disturbances have a coupled vertical structure extending into the lower mesosphere, they are termed Upper Stratospheric/Lower Mesospheric (USLM) disturbances.”American Meteorological Society Conference, Greer et al. 2013

Recent Planetary Wave activity can be see on this Zonal Wave #1 Amplitude Jan, Feb, March Time Series;

NOAA – National Weather Service – Climate Prediction Center – Click the pic to view at source

Zonal Wave #2 Amplitude Jan, Feb, March Time Series;

NOAA – National Weather Service – Climate Prediction Center – Click the pic to view at source

and Zonal Wave #3 Amplitude Jan, Feb, March Time Series:

NOAA – National Weather Service – Climate Prediction Center – Click the pic to view at source

Another likely factor that weakened and split the Polar Vortex is Eddy Heat, i.e. “strong negative fluxes indicate poleward flux of heat via eddies. Multiple strong poleward episodes will result in a smaller polar vortex, Sudden Stratospheric Warmings and an earlier transition from winter to summer circulations. Relatively small flux amplitudes will result in a more stable polar vortex and will extend the winter circulation well into the Spring”  NOAA

Here you can see that 10 day Averaged Eddy Heat Flux Towards The North Pole At 100mb neared a record daily maximum in early January:

NOAA – National Weather Service – Climate Prediction Center – Click the pic to view at source

A third potential factor in Polar Vortex behavior that has been proposed is that “geomagnetic activity (used as a measure of solar wind parameters)” plays a role in the “variability of large-scale climate patterns and on changes in the global temperature. We have found positive statistically significant correlations between global temperature and the distribution of surface temperature over Eurasia, the East and Equatorial Pacific and over the North Atlantic for the period 1966-2009 correspond to large-scale climate patterns defined by climate indices. We found very similar positive correlations between geomagnetic activity and the distribution of surface temperature in the mentioned regions. As an effect of geomagnetic storms, energetic particles penetrate from the magnetosphere into the region of the stratospheric polar vortex. The increase of temperature and pressure can be observed over northern Canada. The vortex shifts towards Europe, rotates counter-clockwise and the wind blows from the polar region over Greenland southwards. It diverts the warm flow proceeding northward over the Atlantic, eastward along the deep Icelandic low extending as far as the Barents Sea and takes part in warming Eurasia. The strengthened zonal flow from Siberia cools the western Pacific with the impact on the warming of the equatorial and eastern Pacific when also a distinct 1976-78 climate shift occurred. Processes in the Atlantic and Pacific play a significant role and a time delay (wind forcing over the previous 1-4 yr) appears to be the most important for the relocation of the oceanic gyres. Results showing statistically significant relations between time series for geomagnetic activity, for the sum of climate indices and for the global temperature help to verify findings concerning the chain of processes from the magnetosphere to the troposphere.” Studia Geophysica & Geodaetica, Bucha 2012

A Coronal Mass Ejection (CME); hit Earth around January 1st:
Ensemble WSA-ENLIL+Cone Model Evolution Movie for Median CME Input Parameters – Dynamic Pressure:

NOAA – Integrated Space Weather Analysis – Click the pic to view at source

and the Magnetosphere was rocking and rolling:

NOAA – Integrated Space Weather Analysis – Click the pic to view at source

However, there is limited evidence to support the influence of Solar activity on Polar Vorticity and in the past Leif has been dismissive of the potential that Solar influences on the upper atmosphere could influence Earth’s climate, i.e.:

Leif Svalgaard says: March 6, 2011 at 12:13 pm

Just The Facts says: March 6, 2011 at 11:03 am
indicate that the causative mechanism behind proton aurora precipitation during high dynamic pressure is connected to the compression of the magnetosphere, which is directly related to the solar wind dynamic pressure. [and other quotes]

“You keep bringing up influences on the upper atmosphere [which are not disputed - but makes for good fill-material that looks like science], but all of these things are either not related to climate at all or, at best, only marginally and unconvincing.
Again, your bar is much too low [to be generous].”

Regardless of the causes, it appears that the result is that an Upper Stratospheric/Lower Mesospheric (USLM) disturbance occurred, i.e. “USLM Disturbance criteria are established, based on stratopause warmings at the 2 hPa level, to create climatologies in both hemispheres that delineate their timing, frequency, and geographic location. USLM disturbances occur on average 2.3 times per winter in the Northern Hemisphere (NH)(November through March) and 1.6 times per winter in the Southern Hemisphere (SH)(May through September), persist on average for 8 days in the NH and only 4 days in the SH, occur most frequently in December (July) in the Northern (Southern) Hemisphere, and are predominantly located in the longitude sector between 0oE and 90oE in both hemispheres. This is the first work to show that all major Sudden Stratospheric Warmings (SSWs) over the 20.5 year data record are preceded by USLM disturbances. One third of USLM disturbances evolve into a major SSW; only 22% of minor SSWs evolve into a major SSW. USLM disturbances and minor SSWs illustrate, at times, similar occurrence statistics, but the minor warming criteria seem to include a more diverse range of dynamical conditions. USLM disturbances are more specific in their dynamical construct with strong baroclinicity being a necessary condition. Potential vorticity analysis indicates that all USLM events occur with planetary wave breaking and that subsequent baroclinic instability may lead to the development of USLM disturbances. A climatology of polar winter stratopause warmings and associated planetary wave breaking”. Greer et al. 2013

“The typical thermal structure of USLM disturbances is dipolar in nature at 2.0 hPa with strong thermal gradients across the polar vortex. From the assimilated data, we find that the geographic preference of the anomalously warm temperatures at 2.0 hPa are located on the East side of the polar low, while there is a related cool pool of air located on the West side. These geographic preferences and observed amplification in temperature help to support the proposed dynamical process of baroclinic instability. Indirect circulations are induced, and to preserve continuity, cells of ageostrophic and vertical motions occur well into the mesosphere, and potentially into the thermosphere. We find that the average frequency of USLM events is 1.63 events per season in the Northern Hemisphere. In addition, the assimilated data indicates that all Sudden Stratospheric Warmings (SSWs) are preceded by USLM events; SSW events occur with a frequency of 0.84 events per season (Northern Hemisphere). USLM disturbances persist from three to ten days and tend to precede SSW events by several days, although there may be multiple USLM disturbances prior to an SSW event occurring. Lastly we exhibit how USLM disturbances differ between the Northern and Southern poles, including differences in frequency and intensity. An open question is whether these frequent USLM polar winter disturbances impact the thermosphere and ionosphere. American Geophysical Union, Greer et al.

“Analysis of planetary wave breaking and EP-flux of individual and composite USLM events indicate an increase in breaking near the 0.1 hPa level, approximately 10 km above the extreme thermal anomaly at the stratopause in the days leading up to the peak of the event. Vertical coupling of the atmosphere during this event is illustrated in the progression of these events and their impact on the thermal structure, zonal mean wind, polar vortex and conditions that have the potential to support a secondary baroclinic instability (including the Charney-Stern criteria for instability the role of baroclinic/barotropic instabilities). In addition, USLM disturbances appear to have front-like behavior analogous to the troposphere. Broader impacts of these disturbances and the dynamics associated with them influence gravity wave generation/propagation, vertical air motion, chemical tracer transport, precondition of the atmosphere for SSWs and the potential to couple with the thermosphere through tides. American Meteorological Society Conference, Greer et al. 2013

The Upper Stratosphere Lower Mesosphere (USLM) Disturbance can be seen on this Jan, Feb, March Zonal Temperature Anomaly Time Series;

NOAA – National Weather Service – Climate Prediction Center – Click the pic to view at source

and the impact of the USLM can be seen in the rapid increase in 10-hPa/mb Height Temperature Anomalies – Atmospheric Temperature Anomalies At Approximately 31,000 meters (101,700 feet) over East Asia:

NOAA – National Weather Service – Climate Prediction Center – Click the pic to view at source

You can see more on current Northern Polar Vortex conditions on the new WUWT Northern Polar Vortex Reference Page. I addition, if you have not had the opportunity to review WUWT’s other Reference Pages it is highly recommended:

Please note that WUWT cannot vouch for the accuracy of the data within the Reference Pages, as WUWT is simply an aggregator. All of the data is linked from third party sources. If you have doubts about the accuracy of any of the graphs on the WUWT Reference Pages, or have any suggested additions or improvements to any of the pages, please let us know in comments below.

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67 Responses to Introducing The New WUWT Northern Polar Vortex Page – With Explanation and Observations

  1. Bill Marsh says:

    Shouldn’t that be ‘Circumpolar Vortex’?

  2. This is important data which needs close watching since I judge that the effect of a variable size and shape for the polar vortices influences jet stream zonality / meridionality and thus global cloudiness to alter the amount of solar energy able to enter the oceans to drive the climate system.

    Such data is relevant to the matter of the ozone hole too.

    I suspect a solar driven link between ozone amounts, global cloudiness and shifting climate zones which in turn influences the vigour of the global convective system that then acts as a negative system response to both warming and cooling.

  3. mrmethane says:

    Excellent presentation and explanation of the phenomenon. I suspect it will be either ignored, misinterpreted or be simply beyond the comprehension of the trolls and warmists. Nice piece of work!

  4. Bill Marsh says: January 18, 2014 at 10:09 am

    Shouldn’t that be ‘Circumpolar Vortex’?

    No, the Circumpolar Vortex and the Polar Vortex are interrelated but distinct phenomena.

    For example, “This paper represents a final summary of the work I have carried out on the 300-mb north circumpolar vortex using these analyses, and includes discussion of the relation between 300-mb vortex size, and vortex depth, midlatitude tropospheric temperature, and Arctic Oscillation (AO) and North Atlantic Oscillation (NAO) indexes.”
    NOAA

    And in his recent WUWT article It’s The Circumpolar Vortex Not The Polar Vortex And Other PR Deceptions ” Tim Ball provided this animation of the Circumpolar Vortex at 500 hPa/mb:
    Circumpolar_vortex_animation

    In comparison, “the polar vortex extends from the tropopause (the dividing line between the stratosphere and troposphere) through the stratosphere and into the mesosphere (above 50 km). Low values of ozone and cold temperatures are associated with the air inside the vortex.” NASA

    This graphic is helpful in seeing the height and location of the Polar Jet in relation to the Tropopause, down to which the Stratospheric Polar Vortex can extend:

    ddata.over-blog.com – Click the pic to view at source

    Additionally, in the following image the Stratospheric Polar Vortex is delineated by the “Arctic Front”, whereas the Circumpolar Vortex is delineated by the “Polar Front”

    clip_image006

    Tim Ball’s point about the Circumpolar Vortex is that the Stratospheric Polar Vortex does not reach down to the surface making it cold. Rather variations in the Polar Vortex can influence the Circumpolar Vortex, which can elongate to allow Polar Air to reach lower latitudes. Additionally, in the center of the Polar Vortex “air from very high altitudes descends vertically through the center of the vortex, moving air to lower altitudes over several months” “NASA”, loading the Arctic with cold air available for breakout.

  5. Stephen Wilde says: January 18, 2014 at 10:34 am

    Such data is relevant to the matter of the ozone hole too.

    Yes, the “Ozone Hole” is likely a result of the dynamical effects of the Stratospheric Polar Vortex, i.e.:

    “The ozone hole is in the center of a spiraling mass of air over the Antarctic that is called the polar vortex. The vortex is not stationary and sometimes moves as far north as the southern half of South America, taking the ozone hole with it.” NASA

    Within the Polar Vortex there are other “holes” as well, i.e.

    “The walls of the polar vortex act as the boundaries for the extraordinary changes in chemical concentrations. Now the polar vortex can be considered a sealed chemical reactor bowl, containing a water vapor hole, a nitrogen oxide hole and an ozone hole, all occurring simultaneously” Labitzke and Kunze 2005

    “measurements of low methane concentrations in the vortex made by the HALOE instrument on board the Upper Atmosphere Research Satellite.” Rapid descent of mesospheric air into the stratospheric polar vortex, AGU 1993

    Also, “in the center of the Antarctic vortex. Air from very high altitudes descends vertically through the center of the vortex, moving air to lower altitudes over several months.”NASA

    Air towards the top of the stratosphere has lower concentrations of ozone;

    NOAA – National Aeronautics and Space Administration (NASA) Goddard Space Flight Center (GSFC) – Click the pic to view at source

    As such, when this “air from very high altitudes descends vertically through the center of the vortex” it displaces the air below it, decreasing the concentration of ozone within the Polar Vortex. The combination of the low pressure area formed by the centrifugal force of the Polar Vortex and the air from very high altitudes with lower concentrations of ozone that “descends vertically through the center of the vortex”, creates the “Ozone Hole”, along with the “Water Vapor Hole”, “Nitrogen Oxide Hole” and “Methane Hole”.

  6. Leon Brozyna says:

    Understanding the why of it all still doesn’t make me any warmer … and just this week we’re looking at temps 10 to 20°F below normal.

    Is it Spring yet???

    Hint … no … and the talk is of temps running about 10°F below normal through to mid-February.

  7. Alec aka Daffy Duck says:

    Layman here with a question: I’ve seen references to stratospheric ozone depletion triggering AO positive, and NSIDC says AO positive pushes arctic ice in into the atlantic by greenland…. But I have never seen ozone depletion sted as one of the causes sea ice loss… Why?

  8. dave says: January 18, 2014 at 11:36 am

    Could you please fix the ending?
    loading the Arctic will cold air available for breakout.

    Corrected, thank you.

  9. Alec aka Daffy Duck says: January 18, 2014 at 11:36 am

    Layman here with a question: I’ve seen references to stratospheric ozone depletion triggering AO positive, and NSIDC says AO positive pushes arctic ice in into the atlantic by greenland…. But I have never seen ozone depletion sted as one of the causes sea ice loss… Why?

    See my comment in response to Stephen Wilde above, i.e. “Ozone Depletion” is likely a misnomer and the result of the dynamical effects of the Polar Vortex . As such “ozone depletion” doesn’t trigger anything per se, rather the Polar Vortex affects Stratospheric Ozone and the Arctic Oscillation.

  10. Policycritic says:

    Thank you. Excellent.

    [Now I have one link to drop on blogs where they claim that melting arctic ice controls the Jet Stream. It's all over it seems these days as an explanation for the recent cold snap in the middle of the US. "Oh noes! The melting arctic ice is causing the Jet Stream to wobble!"]

  11. Chuck L says:

    Can the polar vortex be considered an eddy which detaches from the circumpolar vortex? Thanks.

  12. JTFW said:

    As such “ozone depletion” doesn’t trigger anything per se, rather the Polar Vortex affects Stratospheric Ozone and the Arctic Oscillation.

    I think ozone amounts affect the vertical temperature profile though which would raise or lower the tropopause height towards the poles thus either facilitating or obstructing polar air ‘breakouts’.

    The vortex does of course redistribute such ozone as is available and causes the hole to vary in size accordingly but variations in solar wavelengths and particles seem likely to modulate the supply of ozone.

  13. Daniel Vogler says:

    Great work, sir. I would like to see the Reference page include the Mountain Torque events pic as well. here is where to get it. MTs lead to geopotential waves. Also, Wave#3 isnt necessary. It does not play a significant role in SSWs.

    http://www.esrl.noaa.gov/psd/map/images/reanalysis/aam_total/gltaum.90day.gif

  14. JTFW said:

    “variations in the Polar Vortex can influence the Circumpolar Vortex, which can elongate to allow Polar Air to reach lower latitudes. ”

    Exactly, but the interesting thing is that in order to push the circumpolar vortex in the tropopause outward from the Pole one needs to reduce tropopause height above the Pole which requires a warming of the descending air within the Stratospheric Polar Vortex and not a cooling.

    A warmer stratosphere pushes the tropopause down and a cooler stratosphere allows it to rise.

    We can see that during the recent years of lower solar activity and during the mid 20th century cooler period and in the LIA the outward movement occurred when the sun was less active so the descending air in the Stratospheric Polar Vortex must become warmer when the sun is less active.

    That implies more ozone creation at height and towards the Poles when the sun is less active which is contrary to established climatology.

    But then again note Joanna Haighs comments in light of the observations between 2004 and 2007 that ozone increased above 45km when the sun became less active.

    She suggested that we might have to reverse the sign of the expected atmospheric response to solar variations in parts of the atmosphere.

    I submit that the only way we can get more zonality with an active sun and more meridionalty with a quiet sun is to reverse the sign of the solar effect on ozone amounts above 45km and towards the poles.

    It was already known that an active sun reduces ozone in the mesosphere and the Stratospheric Polar Vortices allow that mesospheric ozone variability to be transmitted down towards the tropopause.

    Thus can an active sun reduce ozone preferentially above the Poles to raise tropopause height,
    pull the AO and AAO back and allow zonal jets

    Whilst a quiet sun will increase ozone preferentially above the poles to reduce tropopause height, push the AO and AAO outward and lead to more meridional jets.

  15. charles nelson says:

    This is a great achievement which cements WUWT’s position as the authoritative atmospheric science site on the web. Congratulations and…thank you!

  16. pat says:

    am hoping this is relevant. BBC is now running the silent/sleeping sun story on regular news broadcasts, & i’m eager to hear some views from WUWT readers with more understanding of these matters than me:

    18 Jan: BBC: Rebecca Morelle, Science reporter: Is our Sun falling silent?
    “I’ve been a solar physicist for 30 years, and I’ve never seen anything quite like this,” says Richard Harrison, head of space physics at the Rutherford Appleton Laboratory in Oxfordshire…
    “It’s completely taken me and many other solar scientists by surprise,” says Dr Lucie Green, from University College London’s Mullard Space Science Laboratory…
    Prof Lockwood says that while UV light varies with solar activity, other forms of radiation from the Sun that penetrate the troposphere (the lower layer of air that sits above the Earth) do not change that much.
    He explains: “If we take all the science that we know relating to how the Sun emits heat and light and how that heat and light powers our climate system, and we look at the climate system globally, the difference that it makes even going back into Maunder Minimum conditions is very small.
    “I’ve done a number of studies that show at the very most it might buy you about five years before you reach a certain global average temperature level. But that’s not to say, on a more regional basis there aren’t changes to the patterns of our weather that we’ll have to get used to.”…
    “This feels like a period where it’s very strange… but also it stresses that we don’t really understand the star that we live with.” says Prof Harrison.
    “Because it’s complicated – it’s a complex beast.”
    http://www.bbc.co.uk/news/science-environment-25743806

    18 Jan: UK Daily Mail: Mark Prigg: Is a mini ice age on the way? Scientists warn the Sun has ‘gone to sleep’ and say it could cause temperatures to plunge
    2013 was due to be year of the ‘solar maximum’
    Researchers say solar activity is at a fraction of what they expect
    Conditions ‘very similar’ a time in 1645 when a mini ice age hit
    http://www.dailymail.co.uk/sciencetech/article-2541599/Is-mini-ice-age-way-Scientists-warn-Sun-gone-sleep-say-cause-temperatures-plunge.html

  17. Daniel Vogler says:

    the Solar influence on the Stratosphere is linked to the type of QBO phase, a decent correlation of SSWs and the QBO phase and solar Flux

    http://f1.nwstatic.co.uk/forum/uploads/monthly_01_2014/post-10577-0-14746500-1389168133.jpg

  18. Robert Clemenzi says:

    I found the following confusing – had to actually look it up

    50 hPa/mb

    Apparently, the more standard way to write this (used by NOAA) is

    50 hPa(mb)

    since a millibar is the same as a hector Pascal. However, I did find both stylings used on the internet.

  19. Daniel Vogler says:

    Also GPH is used. lol Geopotential height. all same values.

  20. This is a paper from 2006 on Ozone concentrations and possible causes – I found it very interesting and is linked to both polar vortices: http://www.appinsys.com/GlobalWarming/Ozone.htm Sort of looks like Ozone concentration is another one of these “natural” variations with a whole lot of variables. The more we know, the less we know we know.

  21. David Larsen says:

    I think the reversed north Atlantic oscillations last year help to precipitate the current polar vortex.

  22. Alan Robertson says:

    pat says:
    January 18, 2014 at 1:20 pm

    “am hoping this is relevant. BBC is now running the silent/sleeping sun story on regular news broadcasts, & i’m eager to hear some views from WUWT readers with more understanding of these matters than me:”

    Prof Lockwood says: ““If we take all the science that we know relating to how the Sun emits heat and light and how that heat and light powers our climate system, and we look at the climate system globally, the difference that it makes even going back into Maunder Minimum conditions is very small.
    _________________________
    That’s it in a nutshell. While there have been periods in history when it looked like variations in the sun’s output might have affected our climate, the correlations never hold up under scrutiny. At present, we can’t say for certain what effect the sun might have on climate.

    disclaimer: I’m no expert.

  23. Policycritic says: January 18, 2014 at 12:08 pm

    [Now I have one link to drop on blogs where they claim that melting arctic ice controls the Jet Stream. It's all over it seems these days as an explanation for the recent cold snap in the middle of the US. "Oh noes! The melting arctic ice is causing the Jet Stream to wobble!"]

    Let me provide a few more. As best I can interpret, the wobbly Jet Steam hypothesis goes like this:

    “The Arctic is heating faster than the rest of the world, hurried along by the disappearance of polar sea ice. Bright white ice reflects energy back into space; dark blue water absorbs it. Arctic temperatures are about 2 degrees Celsius warmer there than they were in the mid-1960s. (The average temperature increase for the Earth’s atmosphere overall is about 0.7 degree C, since 1900.)

    In other words, the temperature difference between the Arctic and North America is shrinking. That’s one factor causing wobbliness in the jet stream, the west-east current that circles the Northern Hemisphere, according to Jennifer Francis, research professor at Rutgers University. Normally, that river of air keeps low-pressure cold air contained above the Arctic and holds higher-pressure warm air above the temperate regions, where most people live.
    Video: Blizzard Business: These Companies in High Demand

    Scientists tend to call the jet stream a “polar vortex,” Francis says.

    A slowing in the jet stream has caused it to zigzag, carrying warmer temperatures farther north than usual—and Arctic cold farther south. “The real story,” Francis says, is that the jet stream is “taking these big swings north and south and that’s causing unusual weather to occur in a number of places around the Northern Hemisphere.” Bloomberg Businessweek

    For starters, if you watch this video below, you see that even Kevin Trenberth thinks the melting sea ice, warming Arctic, wobbly Jet Steam causes cold January weather hypothesis is weak; “So with regards to the Arctic, there are certainly major changes in the Arctic Sea Ice. And those are biggest in the fall. We’ve had record low Arctic Sea Ice, about 40% decline in Arctic Sea Ice overall, since the 1970’s, in September. But the Arctic fills up in the winter time.” “And so at those times of years the Arctic Sea Ice it seems to me plays a much lesser role. The area affected is a lot less, simply because the arctic is land locked.”

    From a data perspective, “The volume of ice measured this autumn is about 50% higher compared to last year.

    In October 2013, CryoSat measured about 9000 cubic km of sea ice – a notable increase compared to 6000 cubic km in October 2012.”

    “About 90% of the increase is due to growth of multiyear ice – which survives through more than one summer without melting – with only 10% growth of first year ice. Thick, multiyear ice indicates healthy Arctic sea-ice cover.

    This year’s multiyear ice is now on average about 20%, or around 30 cm, thicker than last year. ”

    “‘One of the things we’d noticed in our data was that the volume of ice year-to-year was not varying anything like as much as the ice extent – at least in 2010, 2011 and 2012,’ said Rachel Tilling from the UK’s Centre for Polar Observation and Modelling, who led the study.

    ‘We didn’t expect the greater ice extent left at the end of this summer’s melt to be reflected in the volume. But it has been, and the reason is related to the amount of multiyear ice in the Arctic.'” European Space Agency
    This animation demonstrates the increase in ice thickness measured by CryoSat over the last four Octobers:

    European Space Agency – CryoSat – Click the pic to view at source

    Also, Arctic Sea Ice Extent was within two standard deviations of the 1981 – 2010 average for the entirety of 2013;

    National Snow & Ice Data Center (NSIDC) – Click the pic to view at source

    and Northern Hemisphere Sea Ice Area saw its smallest decline since 2006, with a decline less than half of the prior year and it ended 2013 less than .5 Million Sq Km below the 1979 – 2008 average;

    Cryosphere Today – Arctic Climate Research at the University of Illinois – Click the pic to view at source

    Furthermore, if you look at the graph above during the time of the previously most notable polar “outbreak” event i.e. the “January 1985 Arctic outbreak”, Northern Sea Ice Area appears quite close to average and shows minimal variability during the year. However, “The January 1985 Arctic outbreak was the result of the shifting of the polar vortex further south than is normally seen. Blocked from its normal movement, polar air from the north pushed into nearly every section of the eastern half of the United States, shattering record lows in a number of states. The effects of the outbreak were damaging. At least 126 deaths were blamed on the cold snap and 90 percent of the citrus crop in Florida was destroyed in what the state called the “Freeze of the Century.” Florida’s citrus industry suffered $1.2 billion in losses ($2.3 billion in 2009 dollars) as a result of the inclement weather. The public inauguration of President Ronald Reagan for his second term was held in the Capitol Rotunda instead of outside due to the cold weather, canceling the inaugural parade in the process. (Because Inauguration Day fell on a Sunday, Reagan took a private oath on January 20 and the semi-public oath on January 21.) NOAA

    Additionally, if you look at Polar Tropospheric Temperatures;

    Remote Sensing Systems (RSS) – Microwave Sounding Units (MSU) – Click the pic to view at source

    and the associated data :
    1984 6 0.3569
    1984 7 0.2715
    1984 8 -0.1832
    1984 9 0.3030
    1984 10 0.3630
    1984 11 -0.4922
    1984 12 -0.4762
    1985 1 0.4675
    1985 2 -0.9427
    1985 3 -1.0863
    1985 4 -1.5120
    1985 5 -0.1268
    1985 6 -0.1515

    it is apparent that the 1985 “Polar Outbreak” event occurred without “any indication that “the temperature difference between the Arctic and North America (was) shrinking.” It is thus implausable that this is “one factor causing wobbliness in the jet stream” that supposed cause the recent “Polar Outbreak” event.

    I cannot find any observation evidence that supports Jennifer Francis’ wobbly hypothesis.

  24. Robert Clemenzi says:

    The descriptions above talk of the vortex causing cold air to sink and provide more cold air to the pole. The implication is that this some how makes the pole colder. I don’t understand how this is possible. In general, the stratosphere gets warmer with increasing height, even over the poles. As a result, the sinking air should make the poles warmer.

    In addition, there is the consideration of “potential temperature”. Basically, this means that air gets warmer as it moves toward the surface because of the change in pressure – about 9.8K per kilometer. As a result, air from the mesosphere (0°C at about 50km), if moved to the surface, would be over 450°C!

  25. Alan Robertson says:

    justthefactswuwt says:
    January 18, 2014 at 2:13 pm
    ____________________
    How interesting that at the end of your linked video of Dr. Kevin Trenberth (edited by Peter Sinclair,) YouTube suggests a link to Richard Dawkins discussing magical reality.

  26. Alan Robertson says:

    Big oops- I meant to say: “… video of Dr. Kevin Trenberth and Dr. Jennifer Francis“.

  27. Policycritic says:

    Robert Clemenzi says:
    January 18, 2014 at 2:14 pm

    This doesn’t show it (click on earth lower left to change variables): http://earth.nullschool.net

  28. Policycritic says:

    Thanks, JTFW.

  29. Daniel Vogler says: January 18, 2014 at 1:02 pm

    I would like to see the Reference page include the Mountain Torque events pic as well. here is where to get it. MTs lead to geopotential waves.

    Added, i.e. “Vertical and Zonal Integral Of Mountain Torque – 90 Days”

    National Oceanic & Atmospheric Administration (NOAA) – Earth System Research Laboratory (ESRL) – Click the pic to view at source

    Also, Wave#3 isnt necessary. It does not play a significant role in SSWs.

    Removed

    Thank you very much, any other suggested improvements would be most appreciated.

  30. Robert Clemenzi says: January 18, 2014 at 2:14 pm

    The descriptions above talk of the vortex causing cold air to sink and provide more cold air to the pole. The implication is that this some how makes the pole colder. I don’t understand how this is possible. In general, the stratosphere gets warmer with increasing height, even over the poles. As a result, the sinking air should make the poles warmer.

    You are correct that “In general, the stratosphere gets warmer with increasing height”;

    PhysicalGeography.net – Click the pic to view at source

    however, “the polar vortex extends from the tropopause (the dividing line between the stratosphere and troposphere) through the stratosphere and into the mesosphere (above 50 km). Low values of ozone and cold temperatures are associated with the air inside the vortex.” NASA

    If you review the descending Temperature Analyses in my recent article A Sober Look At The Northern Polar Vortex, it is apparent that air within the Polar Vortex is much colder that the air around it, e.g.:

    Starting at 10 hPa/mb – Approximately 31,000 meters (101,700 feet) here we have a Height Analysis showing the low pressure area;

    NOAA – National Weather Service – Climate Prediction Center – Click the pic to view at source

    a Temperature Analysis showing the cold area;

    NOAA – National Weather Service – Climate Prediction Center – Click the pic to view at source

    and Ozone Mixing Ratio map showing the “Ozone Hole” within it:

    NOAA – National Weather Service – Climate Prediction Center – Click the pic to view at source

    In addition, there is the consideration of “potential temperature”. Basically, this means that air gets warmer as it moves toward the surface because of the change in pressure – about 9.8K per kilometer. As a result, air from the mesosphere (0°C at about 50km), if moved to the surface, would be over 450°C!

    But there isn’t the same “change in pressure” within the vortex, as the walls of the vortex maintain the low pressure as the cold air descends. However, when the vortex breaks up, the pressures equalize and we get a Sudden Stratospheric Warming, i.e.:

    “A stratospheric sudden warming is perhaps one of the most radical changes of weather that is observed on our planet. Within the space of a week, North Pole temperatures can increase by more than 50 K (90°F). For example, on 17 January 2009 the temperature at the North Pole near 30 km was about 200 K. Over a 5-day period, the temperature increased to 260 K (a change of 60 K or 108°F).

    These stratospheric sudden warmings are caused by atmospheric waves that originate in the troposphere. The waves are forced by the large-scale mountain systems of the northern hemisphere and the land-sea contrasts between the continents and oceans. The waves are also characterized by their very large scales, typically referred to as planetary-scale waves. The stratospheric wind structure filters the smaller scale waves, only allowing the planetary waves to propagate into the stratosphere. As the waves move upward into the stratosphere they have two effects: first they will often push the polar vortex away from the North Pole—bringing warmer midlatitude air poleward, and second, they produce a downward motion field that also warms the polar region.” NASA

  31. ossqss says:

    Nice job JTF!

    Great posts and exchanges with take aways, thanks all.

    One more acronym to add to the ever increasing list too,,,,, USLM :-)

  32. Daniel Vogler says: January 18, 2014 at 1:24 pm

    the Solar influence on the Stratosphere is linked to the type of QBO phase, a decent correlation of SSWs and the QBO phase and solar Flux

    http://f1.nwstatic.co.uk/forum/uploads/monthly_01_2014/post-10577-0-14746500-1389168133.jpg

    I actually argued the solar – QBO link with Leif a few years ago, but didn’t make any headway.

    “The Influence of the Solar Cycle and QBO on the Late-Winter Stratospheric Polar Vortex”
    Camp et al. 2006:

    “A statistical analysis of 51 years of NCEP–NCAR reanalysis data is conducted to isolate the separate effects of the 11-yr solar cycle (SC) and the equatorial quasi-biennial oscillation (QBO) on the Northern Hemisphere (NH) stratosphere in late winter (February–March). In a four-group [SC maximum (SC-max) versus minimum (SC-min) and east-phase versus west-phase QBO] linear discriminant analysis, the state of the westerly phase QBO (wQBO) during SC-min emerges as a distinct least-perturbed (and coldest) state of the stratospheric polar vortex, statistically well separated from the other perturbed states. Relative to this least-perturbed state, the SC-max and easterly QBO (eQBO) each independently provides perturbation and warming as does the combined perturbation of the SC-max–eQBO. All of these results (except the eQBO perturbation) are significant at the 95% confidence level as confirmed by Monte Carlo tests; the eQBO perturbation is marginally significant at the 90% level. This observational result suggests a conceptual change in understanding the interaction between solar cycle and QBO influences: while previous results imply a more substantial interaction, even to the extent that the warming due to SC-max is reversed to cooling by the eQBO, results suggest that the SC-max and eQBO separately warm the polar stratosphere from the least-perturbed state. While previous authors emphasize the importance of segregating the data according to the phase of the QBO, here the same polar warming by the solar cycle is found regardless of the phase of the QBO.

    The polar temperature is positively correlated with the SC, with a statistically significant zonal mean warming of approximately 4.6 K in the 10–50-hPa layer in the mean and 7.2 K from peak to peak. This magnitude of the warming in winter is too large to be explainable by UV radiation alone. The evidence seems to suggest that the polar warming in NH late winter during SC-max is due to the occurrence of sudden stratospheric warmings (SSWs), as noted previously by other authors. This hypothesis is circumstantially substantiated here by the similarity between the meridional pattern and timing of the warming and cooling observed during the SC-max and the known pattern and timing of SSWs, which has the form of large warming over the pole and small cooling over the midlatitudes during mid- and late winter. The eQBO is also known to precondition the polar vortex for the onset of SSWs, and it has been pointed out by previous authors that SSWs can occur during eQBO at all stages of the solar cycle. The additional perturbation due to SC-max does not double the frequency of occurrence of SSWs induced by the eQBO. This explains why the SC-max/eQBO years are not statistically warmer than either the SC-max/wQBO or SC minimum/eQBO years. The difference between two perturbed (warm) states (e.g., SC-max/eQBO versus SC-min/eQBO or SC-max/eQBO versus SC-max/wQBO), is small (about 0.3–0.4 K) and not statistically significant. It is this small difference between perturbed states, both warmer than the least-perturbed state, that in the past has been interpreted either as a reversal of SC-induced warming or as a reversal of QBO-induced warming.”

    “The mechanism of QBO’s interaction with the polar stratosphere is better understood, and yet many of the reported observational results have not been explained.Holton and Tan (1980, 1982) discovered what is now called the Holton – Tan effect. They found that in composites, according to the phase of the equatorial QBO at 50 hPa, the polar winter temperature is warmer and the polar vortex is more perturbed by planetary waves when the equatorial QBO is in its easterly phase than in its westerly phase. For a possible mechanism, they cited the work of Tung and Lindzen (1979a) on the effect of the position of the zero-wind line on the stationary planetary waves: As the zero-wind line moves more poleward during eQBO, the westerly waveguide for stationary waves is narrowed and located more poleward. This tends to focus the planetary waves more poleward, making the polar vortex more disturbed and hence warmer. Our understanding of wave – mean flow interaction in the stratosphere has progressed considerably since the late 1970s. Instead of the quasi-linear picture of wave – mean interaction in which the zero-wind line plays a crucial role, it is now understood that the dynamics is highly nonlinear in the stratosphere, and planetary waves break in surf zones (McIntyre and Palmer 1984). Nevertheless, the planetary waves do tend to break more poleward during the QBO easterly phase than during the westerly phase when the waveguide is wider and the wave flux is directed more equatorward. Holton and Tan (1980) divided the winter into early winter (November – December) and late winter (January – March). They found, using 16 years of data, that in early winter wavenumber-1 amplitude at 50 hPa is about 40% greater in eQBO than in wQBO, at the 99% confidence level in a Student’s t test. This positive result was later questioned by Naito and Hirota (1997, hereafter NH97) who found that the Holton – Tan result for 1962/63 – 1977/78 failed to hold in the longer record up to 1993/94. NH97 conjectured that the difference found by Holton and Tan was due to the solar cycle because the period used by them happens to contain two solar minima and one maximum. They therefore suggested that Holton and Tan’s result could not be valid in general, it being applicable only to periods with more solar minima than maxima. Gray et al.(2001)’s findings echo these: For the shorter 26-yr period of 1964 – 90, with a bias toward the solar minimum, the correlation between January – February North Polartemperature in the lower stratosphere with the equatorial QBO wind is 0.4 (the negative sign meaning that the pole is warmer during easterly QBO years), but reduces to 0.25 for the 44 winters from 1955 to 1999, including four full solar cycles. Holton and Tan (1980) also found that during late winter the behavior of wave-number 2 was unexpectedly opposite, being about 60% stronger, in the composite mean, during the wQBO than in the eQBO at 96% confidence level. However, when four more years were added to the sample, they found that the significance level dropped to about 90%.”

    Conclusions:
    “1) There is a very well separated state of the polar stratosphere, which occurs during the confluence of a solar cycle minimum and westerly QBO; we denote this state as the “
    least-perturbed state.” This state is statistically distinguished from all other (perturbed) states at more than the 99% confidence level.

    2) Relative to this least-perturbed state, a solar maximum warms the pole by a mean of approximately 4.6 K (7.2 K peak to peak) during the wQBO and also during the eQBO; both results are statistically significant at more than the 95% confidence level. The statistically significant discriminant spatial patterns of the warming take the form of the structure
    associated with sudden stratospheric warmings.

    3) The above result shows that the solar cycle warms the polar stratosphere by the same amount regardless of the phase of the QBO. It then follows that the stratification of the data according to the phase of the QBO is not necessary in order to see the SC response, except for its necessity in defining the reference state.

    4) Relative to the least-perturbed state, easterly QBO also warms the pole by approximately 4 K but at a lower confidence level of 90%. This lowered significance may be due to the fact that the preconditioning of the SSW by a QBO may depend on the equatorial wind at several height layers (Gray et al. 2001; Gray 2003). The spatial structure is also similar to that of the SSW.

    5) Statistically significant results are obtained when perturbations are measured relative to the least-perturbed state. Previous confusion over possible reversals of solar cycle warming or of the Holton – Tan QBO mechanism are now seen to arise from the comparison of one perturbed state with another perturbed state. These differences are not statistically significant due to the similarity of each of the perturbations. In Fig. 9, the differences between perturbed states are denoted by dashed arrows. Two group LDAs between the perturbed states (not
    shown) show that there is an approximately 0.4-K warming from SC-min/eQBO to SC-max/eQBO (i.e., SC perturbation during eQBO) and an approximately 0.3-K cooling from SC-max/wQBO to SC-max/eQBO (i.e., QBO perturbation during the SC-max). The latter result (the small cooling) has been interpreted as a reversal of the Holton – Tan mechanism; however, both of these results have very low statistical significances and so the signs of the
    warming should not be taken seriously.”

    “The Influence of the Solar Cycle and QBO on the Late-Winter Stratospheric Polar Vortex, Lu et al.

    “SIGNALS OF SOLAR WIND DYNAMIC PRESSURE IN THE NORTHERN ANNULAR MODE AND THE EQUATORIAL STRATOSPHERIC QUASI-BIENNIAL OSCILLATION”

    They “report statistically measurable responses of the Northern Annular Mode (NAM) and the equatorial stratospheric Quasi-biennial Oscillation (QBO) to solar wind dynamic pressure. When December to January solar wind dynamic pressure is high, the Northern Hemispheric (NH) circulation response is marked by a stronger polar vortex and weaker sub-tropical jet in the upper to middle stratosphere. As the winter progresses, the Arctic becomes colder and the jet anomalies shift poleward and downward. In spring, the polar stratosphere becomes anomalously warmer. At solar maxima, significant positive correlations are found between December to January solar wind dynamic pressure and the mid- to late winter NAM all the way from the surface to 20 hPa, implying a strengthened polar vortex, reduced Brewer-Dobson circulation and enhanced stratosphere-troposphere coupling. The combined effect of high solar UV irradiance and high solar wind dynamic pressure in the NH mid- to late winter is enhanced westerlies in the extratropics and weaker westerlies in the subtropics, indicating that more planetary waves are refracted towards the equator. At solar minima, there is no correlation in the NH winter but negative correlations between December to January solar wind dynamic pressure and the NAM are found only in the stratosphere during spring. Statistical evidence of a possible modulation of the equatorial stratospheric Quasi-biennial Oscillation (QBO) by the solar wind dynamic pressure is also provided. When solar wind dynamic pressure is high, the QBO at 30-70 hPa is found to be preferably more easterly during July to October. These lower stratospheric easterly anomalies are primarily linked to the high frequency component of solar wind dynamic pressure with periods shorter than 3-years. In annually and seasonally aggregated daily averages, the signature of solar wind dynamic pressure in the equatorial zonal wind is characterized by a vertical three-cell anomaly pattern with westerly anomalies both in the troposphere and the upper stratosphere and easterly anomalies in the lower stratosphere. This anomalous behavior in tropical winds is accompanied by a downward propagation of positive temperature anomalies from the upper stratosphere to the lower stratosphere over a period of a year. These results suggest that the solar wind dynamic pressure exerts a seasonal change of the tropical upwelling which results in a systemic modulation of the annual cycle in the lower stratospheric temperature, which in turn affects the QBO during Austral late winter and spring. These results suggest possible multiple solar inputs. Their combined effect in the stratosphere may cause refraction/redistribution of upward wave propagation and result in projecting the solar wind signals onto the NAM and the QBO. The route by which the effects of solar wind forcing might propagate to the lower atmosphere is yet to be understood.”

    “Possible solar wind effect on the northern annular mode and northern hemispheric circulation during winter and spring, Lu et al.

    Found “statistically measurable responses of atmospheric circulation to solar wind dynamic pressure are found in the Northern Hemisphere (NH) zonal-mean zonal wind and temperature, and on the Northern Annular Mode (NAM) in winter and spring. When December to January solar wind dynamic pressure (P sw DJ) is high, the circulation response is marked by a stronger polar vortex and weaker sub-tropical jet in the upper to middle stratosphere. As the winter progresses, the Arctic becomes colder and the jet anomalies shift poleward and downward. In spring, the polar stratosphere becomes anomalously warmer. At solar maxima, significant positive correlations are found between P swDJ and the middle to late winter NAM all the way from the surface to 20 hPa, implying a strengthened polar vortex, reduced Brewer–Dobson circulation and enhanced stratosphere-troposphere coupling. The combined effect of high solar UV irradiance and high solar wind dynamic pressure in the NH middle to late winter is enhanced westerlies in the extratropics and weaker westerlies in the subtropics, indicating that more planetary waves are refracted toward the equator. At solar minima, there is no correlation in the NH winter but negative correlations between P swDJ and the NAM are found only in the stratosphere during spring. These results suggest possible multiple solar inputs that may cause refraction/redistribution of upward wave propagation and result in projecting the solar wind signals onto the NAM. The route by which the effects of solar wind forcing might propagate to the lower atmosphere is yet to be understood.”

    There appear to be correlations between solar wind dynamic pressure and the NAM and QBO. However, Leif argued that there is no known mechanism whereby ”the effects of solar wind forcing might propagate to the lower atmosphere”. At this point I would argue that Polar Vortex Perturbation is at least plausible.

  33. Chuck L says: January 18, 2014 at 12:08 pm

    Can the polar vortex be considered an eddy which detaches from the circumpolar vortex? Thanks.

    No, the Stratospheric Polar Vortex and Circumpolar Vortex are separate and distinct phenomena occurring in different locations and altitudes on Earth:

    This and this are animations of the current Polar Vortex and this is an animation of what it looks like when a Polar Vortex breaks up. Conversely, this and this are animations of the Circumpolar Vortex.

    This image should help to visualize the separation:

    Kavli Institute for Theoretical Physics – University of California – Click the pic to view at source

    “Even a simplified model of the Earth’s atmosphere that has only two layers at different altitudes reproduces observed features of the general circulation such as jet streams, storm tracks, and trade winds. Colors in the image represent the wind vorticity averaged over the two levels. Image by Brad Marston.” this and KITP

  34. Chuck L says: January 18, 2014 at 12:08 pm

    It is also helpful to note that:Planetary Vorticity “is zero at equator, is maximum at pole (one revolution per day)” and “is always positive (cyclonic)”. Lyndon State College Atmospheric Sciences

    Lyndon State College Atmospheric Sciences – Click the pic to view at source

  35. Louis says:

    “The cold experienced in early January was actually a result of the polar vortex weakening, becoming warmer and therefore releasing its powerful chill beyond its normal reach through the northern climes, NOAA says.”

    Funny, that sounds just like my ex. As she becomes warmer, she releases a powerful chill beyond her normal reach. Saying that something is more likely to release a powerful chill when it is warmer may sound like a contradiction, but CO2 is a devious molecule that can do all sorts of magical things. Why it can cause global heat waves or prolonged global cooling depending on its mood. To be truthful, we have absolutely no clue which one will happen next. But right after it happens, we will be quick to say, “I told you so!”

  36. Not only does Saturn have a Polar Vortex, it is inexplicably hexagonal.
    It has got to be something like a natural harmonic, but it is a spinning hexagonal storm 20,000 miles in diameter that has been there whenever we’ve looked for the past 30 years. There are signs of it in Voyager photos. But Cassini got a long sustained view of it in it’s Polar Mission phase a couple of years ago. See also Astronomy Pic of the Day Feb. 20, 2013

  37. Clive says:

    Very neat JTF. Thanks, it is good info to have.
    Sigh! I remember when we just had winter.
    You know? It got cold on and off for a few months. ☺ Then we had something called spring and summer, although here in Canuckistan the lines were often blurred and if you did not know the actual date, you might not know what season it really was. And then we had winter again. Now we have the polar vortex. A hex on the vortex. ☺
    No PV here in southern Alberta these a past few days. Was 11°C here and sunshine all day.
    Thanks again. Good stuff.
    CAS

  38. crosspatch says:

    Speaking of “Polar Vortex”, the governor of OH has declared an “energy emergency” and is calling out the National Guard. They can’t get fuel oil and propane to people fast enough so he has suspended regulations that limit “in service” hours for drivers. Here is the order:

    http://www.ema.ohio.gov/Documents/Releases/2014/20140118_StateOfEnergyEmergency.pdf

  39. ren says:

    Ionizing radiation is focused on the polar circle, and increases in the period of low solar activity.
    http://terra2.spacenvironment.net/~raps_ops/current_files/rtimg/dose.15km.png

  40. Pat Nugent says:

    one can have “a phenomenon”,” two or more phenomena”, but not “a phenomena [sic].

  41. Gunga Din says:

    Mr. Layman here. (Maybe I should change my screen-name to that?)
    Thanks.
    Have I got this basically right?
    1. “Polar Vortex” is nothing new.
    2. “Polar Vortex” has not been commonly used to describe winter weather events to the public.
    3. “Polar Vortex” is now being used to make what is a normal winter weather event seem “abnormal” or “weird” to the public?
    (I realize that 1 and 2 may be asking for more of an opinion than a provable fact.)

  42. Gunga Din says:

    DANG!
    Typo!
    “(I realize that 1 and 2 may be asking for more of an opinion than a provable fact.)”
    Should be:
    “(I realize that 2 and 3 may be asking for more of an opinion than a provable fact.)”

  43. Gunga Din says:

    (Maybe instead of “TYPO!” I should have said “BRAINO)!”?

  44. Caleb says:

    Thanks for all the information. I am going to bookmark this post and return to it, for there is no way my brain cells can absorb all this information all at once. However it will be a nice, rich feast to peruse from time to time. In around ten years, if I’m still alive, I may start to comprehend the many different layers of weather and how they all interact.

    I tend to stick to nice, simple surface maps. Judging from those maps the low pressure areas in the arctic do seem to run along the edge of the ice, especially in the fall when the air over the ice is rapidly getting colder, while the air over the northern tendrils of the Gulf Stream remains close to freezing. I’ve seen 2m temperature isotherm differences as great as sixty degrees (plus thirty as opposed to minus thirty) squished very close together along the Siberian coast. Then, as the seas north of Siberia freeze from east to west, the storms loose their power further and further west. The lows seem to weaken over ice the same way hurricanes weaken over land.

    Of course this is all happening down on ground level, and not up where the jet streams cruise.

  45. Mike Maguire says:

    This is fantastic work and information. Here is what I want everybody to do to appreciate this recent Arctic air mass and the real reason for it better. Go to the link below, which will allow you to access reanalysis data(weather maps) from NOAA going back to 1948.

    Put in a starting date of (year)1976 (month)11 (day)26 (cycle) 00
    Let’s try an ending date of 1977 02 02

    http://www.hpc.ncep.noaa.gov/ncepreanal/

    Look how many times the “Polar Vortex” becomes displaced by thousands of miles and on 3 separate occasions in January, 1977, dives into the United States very similar to what we saw earlier this month.

    Tell me again what CO2 levels were back in the Winter of 1976/77.

    Here’s what’s going on. The weather/climate is following something like a 30 year natural cycle of warming and cooling. It’s blatantly obvious to anybody with open eyes/brains using pattern recognition looking at a global temperature graph going back 120 years.

    We finished the warming phase just over a decade ago which meant that by the late 1990’s, those with bad memories and or too lazy or biased to look at the weather/climate during previous cooling and warming periods were making assumptions based on ignorance of the past.

    So now that our planet is back in the cooling phase, which correlates well with some oceanic indices like the PDO that flip/reverse in sign every 30 years (but also “may” have a new element involving the sun which makes it more interesting) we have those ignorant of the past, coming up with ignorant statements like this:

    “A growing body of evidence suggests that the kind of extreme cold being experienced by much of the United States as we speak is a pattern that we can expect to see with increasing frequency as global warming continues”

    John Holden really did say this.
    http://www.examiner.com/article/white-house-polar-

    The main reason for this recent extreme cold was similar to the more numerous extreme cold outbreaks of the Winter of 76/77……………and many, many other ones in our history which featured massive blobs of Arctic air and a deep, cutoff upper level low being displaced very far south of their origin.

    It had nothing to do with humans, CO2 or global warming.

  46. Gunga Din says: January 19, 2014 at 1:40 pm

    1. “Polar Vortex” is nothing new.

    Correct, the book Living Age from 1853 references the Polar Vortex and Google Scholar brings back 16,100 citations for Polar Vortex”:
    http://scholar.google.com/scholar?hl=en&q=%22polar+vortex%22&btnG=&as_sdt=1%2C31&as_sdtp=

    2. “Polar Vortex” has not been commonly used to describe winter weather events to the public.

    Correct, prior to 2014 the Google Trend for “Polar Vortex” is almost dead:
    http://www.google.com/trends/explore#q=polar%20vortex&date=1%2F2004%20121m&cmpt=q

    However, it is important to note this January 25, 2011, New York Times article Cold Jumps Arctic ‘Fence,’ Stoking Winter’s Fury and associated NYT blog post Frigid Winters and the Polar Vortex, which both reference the Polar Vortex.

    3. “Polar Vortex” is now being used to make what is a normal winter weather event seem “abnormal” or “weird” to the public?

    Correct, though a lot of this can be attributed to sensationalism versus an organized disinformation campaign, i.e.:

    John Holdren, Jennifer Francis and numerous others are currently disingenuously trying to use the Polar Vortex to explain why warming causes cooling. However, I encourage them, as the warming causes cooling meme is a sure fire loser. All but a brainwashed lemming can see that John, Jennifer and company are contorting themselves to try to cram polar breakouts and freezing temps into the rapidly crumbling Catastrophic Anthropogenic Global Warming Narrative. One does not need to understand the intricacies of Polar Vorticity in order to know when one is being lied to. I expect that when we see the next round of survey results, the Polar Vortex and Ship of Fools memes will result in “Global warming denial” hitting new highs, i.e. Global warming denial hits a six-year high:

    “The percentage of Americans who believe global warming is human-caused has also declined, and now stands at 47 percent, a decrease of 7 percent since 2012.”

    “The obvious question is, what happened over the last year to produce more climate denial?

    According to both Anthony Leiserowitz of Yale and Ed Maibach of George Mason, the leaders of the two research teams, the answer may well lie in the so-called global warming “pause” — the misleading idea that global warming has slowed down or stopped over the the past 15 years or so. This claim was used by climate skeptics, to great effect, in their quest to undermine the release of the U.N. Intergovernmental Panel on Climate Change’s Fifth Assessment Report in September 2013 — precisely during the time period that is in question in the latest study.”

    “Nonetheless, widely publicized “pause” claims may well have shaped public opinion. “Beginning in September, and lasting several months, coincident with the release of the IPCC report, there was considerable media attention to the concept of the ‘global warming pause,’” observes Maibach. “It is possible that this simple — albeit erroneous — idea helped to convince many people who were previously undecided to conclude that the climate really isn’t changing.”

    “Even more likely, however,” Maibach adds, “is that media coverage of the ‘pause’ reinforced the beliefs of people who had previously concluded that global warming is not happening, making them more certain of their beliefs.”

    “Journalists take heed: Your coverage has consequences. All those media outlets who trumpeted the global warming “pause” may now be partly responsible for a documented decrease in Americans’ scientific understanding.”

    In summary, I am not concerned with the media’s interpretation, or more commonly misinterpretation, of the Polar Vortex, as it plays into our hands by showing more people how little we really know about Earth’s climate system. This image sums up my perspective on the media’s embrace of the Polar Vortex:

    memegenerator.net – Click the pic to view at source

  47. Gunga Din says:

    justthefactswuwt says:
    January 19, 2014 at 6:33 pm

    Gunga Din says: January 19, 2014 at 1:40 pm

    ============================================================================
    Thanks. I can’t always follow the science but I do better with the “PR”.
    (Mexican beer caused the Polar Vortex? 8-)

  48. ren says:

    Solar activity decreases. Grows cosmic rays. Winter will be long ..
    http://cosmicrays.oulu.fi/webform/monitor.gif

  49. Box of Rocks says:

    Are there any good 3 dimensional representations of air flow to and from the poles?

    It seems to me that if there is sufficient cold air to move south from the arctic, warm air must have been transported there to begin with, right?

    The amount of air on the planet does not vary much, it just seems to move around a lot and as it moves it displaces air.

  50. George Kominiak says:

    Nice work!! I hope it’s not all in vain. This morning, ABC News called the latest outbreak of cold air the “POLAR PLUNGE!” To her credit, Ginger Zee, the meterologist/reporter, seemed to be a bit embarassed at the “new” terminology.

  51. ren says:

    Can be seen how air inflow up from the the pole over the North America.
    http://earth.nullschool.net/jp/#current/wind/isobaric/10hPa/orthographic=-355.55,93.41,319

  52. Gunga Din says:

    George Kominiak says:
    January 20, 2014 at 12:09 pm

    Nice work!! I hope it’s not all in vain. This morning, ABC News called the latest outbreak of cold air the “POLAR PLUNGE!” To her credit, Ginger Zee, the meterologist/reporter, seemed to be a bit embarassed at the “new” terminology.

    ========================================================================
    Maybe the “Polar Plunge” will be the plunger the public needs for all the CAGW BS that has plugged up the system.

  53. Nature seems to know a hexagon. Here’s a photo of Saturn’s Polar Vortex.
    Snowflakes are all hexagons too:
    http://www.natureworldnews.com/articles/5197/20131205/saturns-unique-hexagon-jet-stream-captured-gifs-nasas-cassini-probe.htm

  54. No two snowflakes are alike, but they are all hexagons. Haven’t seen one yet that’s a pentagon. Anyone here know (have a scientific reason) why Saturn’s polar vortex is in the shape of a hexagon??? Maybe God likes hexagons…

  55. ren says: January 18, 2014 at 11:45 pm

    http://geo.phys.spbu.ru/materials_of_a_conference_2012/STP2012/Veretenenko_%20et_all_Geocosmos2012proceedings.pdf

    Interesting, i.e. THE POLAR VORTEX EVOLUTION AS A POSSIBLE REASON FOR THE TEMPORAL VARIABILITY OF SOLAR ACTIVITY EFFECTS ON THE LOWER ATMOSPHERE CIRCULATION S.V. Veretenenko:

    “It was revealed that the detected earlier ~60-year oscillations of the amplitude and sign of SA/GCR effects on the troposphere pressure at high and middle latitudes are closely related to the state of a cyclonic vortex forming in the polar stratosphere. A roughly 60- year periodicity was found in the vortex strength affecting the evolution of the large-scale atmospheric circulation and the character of SA/GCR effects. It was shown that the sign reversalsof the correlations between tropospheric pressure and SA/GCR variations coincide well with the transitions between the different states of the vortex. Most pronounced SA/GCR influence on the development of extratropical baric systems is observed when the vortex is strong. The resultsobtained suggest that the evolution of the stratospheric polar vortex plays an important part in the mechanism of solar-atmospheric links.”

    “We can see that the temperature in the vortex center decreases with the increase of height and reaches its minimum at the levels 30-50 hPa (20-25 km). The temperature gradients at the vortex edges increase with height in the stratosphere starting from the level 150 hPa, their maximum being observed at the levels 50-10 hPa (20-30 km). In the troposphere temperature gradients are maximal near surface corresponding to Arctic fronts separating the Arctic air from warmer air of middle latitudes. Thus, the vortex is most pronounced at the 50-30 hPa levels where the minimum of stratospheric temperatures and the maximum of temperature gradients at its edges are observed. We can see that the highest values of ion production rate due to GCR are observed in the lower part of the vortex (10-15 km) where temperature gradients start increasing. On the other hand, the 11-year modulation of GCR fluxes is strongest at the heights 20-25 km [Bazilevskaya et al., 2008] where the vortex is most pronounced. Hence, the vortex location seems to be favorable for the mechanisms of solar activity influence on the atmosphere circulation involving GCR variations. It is also favorable for the mechanisms involving solar UV variations, as at these heights (15-25 km) in the polar stratosphere the maximum ozone content is observed. The evolution of the vortex is known to be determined by dynamic coupling between the troposphere and stratosphere via planetary wave propagation, as well as by radiation processes in the stratosphere. So, we can suggest that the mechanism of SA/GCR influence on the troposphere circulation involves changes of the vortex strength associated with changes of the heat-radiation balance in the stratosphere. These changes may be caused by variations of atmosphere transparency in visible and infrared range associated with the effects of ionization and atmospheric electricity variations on cloudy and aerosol particle characteristics [Tinsley, 2008]. Indeed, a considerable increase of aerosol concentration at high latitudes which was most pronounced at the heights 10-12 km and accompanied by the temperature decrease in overlying stratospheric layers was detected during a series of powerful solar proton events on January 15-20, 2005 [Veretenenko et al., 2008]. In turn, the increase of the vortex strength intensifies temperature gradients at its edges (see Fig.4). At the stages of a strong vortex this increase of temperature gradients may be transferred to the troposphere via planetary waves and contribute to the increase of temperature contrasts in tropospheric frontal zones and the intensification of extratropical cyclogenesis.”

    5. Conclusions
    The results of this study showed that the evolution of the stratospheric polar vortex plays an important part in the mechanism of solar-climatic links. The vortex strength reveals a roughly 60-year periodicity influencing the large-scale atmospheric circulation and the sign of SA/GCR effects on the development of baric systems at middle and high latitudes. The vortex location is favorable for the mechanisms of solar activity influence on the troposphere circulation involving variations of different agents (GCR intensity, UV fluxes). In the periods of a strong vortex changes of the vortex intensity associated with solar activity phenomena seem to affect temperature contrasts in tropospheric frontal zones and the development of extratropical cyclogenesis.”

    ren says: January 19, 2014 at 11:39 pm

    Solar activity decreases. Grows cosmic rays. Winter will be long ..
    http://cosmicrays.oulu.fi/webform/monitor.gif

    Added to the WUWT Solar Reference Page and the WUWT Atmosphere Page:

    Cosmic Rays

    Oulu Neutron Monitor

    University of Oulu – Sodankyla Geophysical Observatory – Click the pic to view at source

    However, not yet added to the WUWT Polar Vortex Reference Pages, as I am not yet convinced that there’s a relationship.

    ren says: January 20, 2014 at 6:13 am

    AO clearly declining.
    http://www.cpc.ncep.noaa.gov/products/precip/CWlink/daily_ao_index/ao.obs.gif

    Added to the WUWT Atmospheric Oscillation page, there’s a version under the Normalized Geopotential Height (GPH) Anomaly image, but the one you provided has better resolution, i.e.:

    Arctic Oscillation (AO) Index – 4 Months Prior

    NOAA – National Weather Service – Climate Prediction Center – Click the pic to view at source

    Thank you for your input and contribution. Additional potential content for the WUWT Reference pages, or in support of the relationship between Cosmic Ray and Polar Vorticity, is most welcome.

  56. ren says:

    Thank you. There are other scientific evidence.
    http://icrc2009.uni.lodz.pl/proc/pdf/icrc0228.pdf
    Ionizing radiation also depends on the pressure, which can be seen on the monitor. Ozone can be reduced by rapid electrons GCR.
    http://terra2.spacenvironment.net/~raps_ops/current_files/rtimg/dose.15km.png

  57. ren says:

    Strength of cosmic rays GCR is opposite to the Earth’s magnetosphere activity (Ap) and depends on the Earth’s magnetic field. Is strongest at the poles.

  58. ren says:

    I have a theory based on my observation that if cosmic rays are high for many years, as now, since 2005, the changes in ozone zone cumulative, by going in the high parts of the stratosphere with one pole of the Earth to the other.

  59. Carla says:

    Thanks Justthefacts, good presentation.
    ren’s input is valuable here too, IMO. Something we should be keeping an eye on.

  60. “The association between stratospheric weak polar vortex events and cold air outbreaks in the Northern Hemisphere” Kolstad et al. 2010

    “Previous studies have identified an association between temperature anomalies in the Northern Hemisphere and the strength of stratospheric polar westerlies. Large regions in northern Asia, Europe and North America have been found to cool during the mature and late stages of weak vortex events in the stratosphere. A substantial part of the temperature changes are associated with changes in the Northern Annular Mode (NAM) and North Atlantic Oscillation (NAO) pressure patterns in the troposphere. The apparent coupling between the stratosphere and the troposphere may be of relevance for weather forecasting, but only if the temporal and spatial nature of the coupling is known.Using51wintersofre-analysisdata, we show that the development of the lower-tropospheric temperature relative to stratospheric weak polar vortex events goes through a series of well-defined stages, including the formation of geographically distinct cold air outbreaks. At the inception of weak vortex events, a precursor signal in the form of a strong high-pressure anomaly over north west Eurasia is associated with long-lived and robust cold anomalies over Asia and Europe. A few weeks later, near the mature stage of the weak vortex events,a shorter-lived cold anomaly emerges off the east coast of North America. The probability of cold air outbreaks increases by more than 50% in one or more of these regions during all phases of the weak vortex events.This shows that the stratospheric polar vortex contains information that can be used to enhance forecasts of cold air outbreaks. As large changes in the frequency of extremes are involved, this process is important for the medium-range and seasonal prediction of extreme cold winter days. Three-hundred-year pre-industrial control simulations by 13 coupled climate models corroborate our results.”

    “Cold air outbreaks (CAOs) are departures of cold airmasses into warmer regions. Over land, these events can lead to deaths and damage (Mercer, 2003; Barnett et al., 2005; Pinto et al., 2007). Over the ocean, CAOs are important for a number of reasons: they give rise to mesoscale weather phenomena such as polar lows (Bracegirdle and Gray, 2008), they lead to enhanced heat and momentum fluxes from the ocean to the air (Renfrew and Moore, 1999) and may therefore influence the ocean circulation (Pickart et al., 2003), and they cause rapid formation of sea ice in marginal ice zones (Skogseth et al., 2004). In recent years it has emerged that anomalies in the stratospheric circulation can be associated with tropospheric CAOs (Thompson et al., 2002; Cai and Ren, 2007; Scaife et al., 2008). Normally, the extratropical stratosphere is characterised by a strong westerly circumpolar flow. In winter, planetary waves of tropospheric origin propagate continuously into the stratosphere (Charney and Drazin, 1961), where they break and exert a drag on the zonal flow (McIntyre and Palmer, 1983; Polvani and Waugh, 2004). This violates the geostrophic balance and induces a poleward drift of air masses. At high latitudes, the air converges, sinks and warms adiabatically. If there is severe wave-breaking, the stratospheric zonal flow reverses, giving rise to stratospheric sudden warmings (SSWs: Matsuno, 1971), which may last for days to weeks (Limpasuvan and Hartmann, 1999). After their first appearance in the upper stratosphere, circulation anomalies are occasionally found at successively lower levels (Matsuno, 1970; Lorenz and Hartmann, 2003). After reaching the tropopause, the anomalies may impact the troposphere through an interaction with synoptic-scale eddies (Song and Robinson, 2004), ormore directly through induced meridional circulations. As a result, a negative Northern Annular Mode (NAM: Thompson and Wallace, 2001) and North Atlantic Oscillation (NAO: Hurrell et al. 2003) pattern may occur near the surface some weeks after the first warming signal in the upper stratosphere (Baldwin and Dunkerton, 2001; Baldwin et al., 2003; Limpasuvan et al., 2004).

    Negative NAM and NAO regimes in the troposphere have a profound influence on the weather in large and widespread regions of the Northern Hemisphere (NH) (Kenyon and Hegerl, 2008).Atlantic and Pacific storm tracks shift latitudinally (Hurrell and Van Loon, 1997; Baldwin and Dunkerton, 2001), Greenland and Newfoundland warm (Thompson et al., 2002), and the frequency and severity of CAOs increase over large parts of east Asia (Chen et al., 2005; Jeong and Ho, 2005), northern Eurasia (Scaife et al., 2008) and eastern North America (Thompson and Wallace, 2001; Walsh et al., 2001; Cellitti et al., 2006). Over the ocean, negative phases of the NAO, and positive height anomalies over Greenland in particular, are associated with marine CAOs over the Nordic Seas (Kolstad et al., 2009). Motivated by the link that has been observed between anomalous stratospheric events and the tropospheric climate, we aim to provide a detailed description of tropospheric cold anomalies in relation to such events. Thompson et al. (2002) investigated the mean temperature response during the first 60 days after the onset dates of stratospheric anomalous vortex conditions. Here, we extend their work by assessing the temperature development and changes in the probability of CAOs at different stages of stratospheric weak vortex events. We find that the tropospheric temperature development goes through several distinct and well-defined stages of stratospheric weak vortex events and we identify CAOs over both continental and oceanic regions. These results are corroborated by data from 300-year time slices of 13 coupled model simulations.”

    “Our analysis is centred on composites of days and months for which the stratospheric vortex is weak. We define Weak vortex days (WVDs) in the NNR as the days for which the daily VSI falls below its overall wintertime (December–March) 10th percentile. An alternative to this method would be to remove the seasonal cycle (by using the date-wise climatological 10th percentile as a threshold instead), but this would have forced the WVDs to be equally distributed among the wintermonths. Cold days are defined as days with an 850 hPa temperature below its date-wise climatological 10th percentile. When identifying cold days we did remove the seasonal cycle, as the purpose of defining cold days is to assess whether a given day is colder than ‘normal’. Weak vortex months (WVMs) and Cold months in the models are defined with respect to the overall 10th percentiles of the monthly mean anomalies.”

    “In Figure 1(a), a matrix of VSI values for each day in the analysis period is shown. The values were grouped with respect to deciles. The blue days are the WVDs as defined above. The SSW central dates are shown using crosses. As mentioned earlier, due to the way they were computed, the density of WVDs is higher in midwinter than in early and late winter. Figure 1(a) shows that this complies well with the seasonal distribution of the SSW central dates. An advantage of CP07’s approach is that all their events are independent, and the study of lead/lag processes is therefore free of the effects of artificial smoothing.”

    The association between stratospheric weak polar vortex events and cold air outbreaks in the Northern Hemisphere, Kolstad et al. 2010 – Click the pic to view at source

    “The relationship between stratospheric weak vortex events and tropospheric developments, and cold air outbreaks (CAOs) in particular, were investigated using 51 winters of re-analysis data and a set of coupled climate models. We found large increases in the frequency of cold air outbreaks (Figure 3) that coincide geographically with the regions of mean temperature change (Figure 2). The probability of CAOs was found to increase: (1) by 75% or more in some regions of northern Asia throughout the life cycle of weak vortex events (from the Precursor phase to the Decay phase), (2) by 50% or more in some regions of Europe (from the Onset phase to the Decline phase), and (3) by 50% or more in the Peak phase off the east coast of North America. Changes in the frequency of cold air outbreaks associated with the stratosphere are therefore large compared to the climatological incidence of CAOs. Such substantial changes make this signal important for the long-range forecasting of the likelihood of CAOs. If the signal is predictable, then there will be an associated predictability of CAOs. However, if it is unpredictable, then it represents an important limit on the long-range predictability of CAOs.

    A potential obstacle to the predictability of CAOs based on the state of the stratospheric vortex is the fact that many of the cold anomalies seen in Figure 3 occurred before the SSW central dates and WVDs. The early CAOs in Europe and Asia were associated with the perhaps clearest precursor of stratospheric weak vortex events, a high pressure anomaly centred over the northwestern edge of Eurasia in the Precursor, Onset and Growth phases. Although its location changed with time, this positive height anomaly persisted for all the phases and was confined to high latitudes in the Atlantic sector. More work is therefore needed to address the chain of cause and effect and to investigate tropospheric precursors of weak vortex events, adding to existing studies of troposphere–stratosphere interactions (Kuroda and Kodera, 1999; Chen et al., 2003; Polvani and Waugh, 2004; Reichler et al., 2005; Scaife et al., 2005; Cohen et al., 2007; Martius et al., 2009; Mukougawa et al., 2009; Garfinkel et al., 2010). We did not directly address the issue of cause and effect of CAOs in this paper, but interestingly, we found a hemisphere-wide pattern of lower-tropospheric temperature signals both before and after weak vortex events. In general, such temperature signals are associated with pressure anomaly dipoles in the form of anomalous ridges upstream (such as the precursory high anomaly over northwest Eurasia) and anomalous troughs downstream of the cold anomalies. Such patterns lead to changes to the flow, and the resulting temperature advections may well act as positive feedback mechanisms, as documented for the negative phase of the surface NAM(Thompson and Wallace, 2000). The association between pressure anomaly dipoles and CAOs is known from previous studies (Konrad, 1996; Walsh et al., 2001; Chen et al., 2005; Takaya and Nakamura, 2005; Cellitti et al., 2006; Kolstad et al., 2009). It is quite possible that some of the regional CAOs identified in this paper are at least partly set up or sustained by cold air advection, as part of the chain of events outlined by Konrad (1996).

    Given the strong stratospheric link to many CAOs, it could be that attention needs to be paid to the simulation of the stratosphere in climate models. However, parts of our analysis were repeated with an ensemble of 13 coupled climate models. Somewhat surprisingly, considering that many of these models have low model tops and poorly resolved stratospheres (Cordero and Forster, 2006), the model results corroborated the relationships between the weak vortex events and the cold anomalies listed above. This may indicate that the main aspects of the tropospheric temperature developments during the life cycle of the stratospheric weak vortex events are associated with internal processes in the troposphere and lower stratosphere, as suggested by Polvani and Waugh (2004).”
    https://www.academia.edu/223963/The_association_between_stratospheric_weak_polar_vortex_events_and_cold_air_outbreaks_in_the_Northern_hemisphere

  61. “Winter turned fierce in the opening weeks of 2009. A bitter cold snap set in over much of the United States, and temperatures plummeted beyond -30 degrees Celsius (-22 F) in parts of the Upper Midwest. On February 2, portions of Western Europe were doused with heavy snow. England received the brunt of the storm with up to 20 centimeters (8 inches) of snow falling in London. It was the heaviest snowfall southeastern England had seen in nearly 20 years, reported BBC News. So why all the nasty weather? Part of the answer lies in the stratosphere, some 20 kilometers (12 miles) above the Earth’s surface.

    Starting in January and extending into early February 2009, wind and temperature patterns in the stratosphere changed dramatically. In just a few weeks, temperatures climbed by about 50 degrees Celsius (90 degrees F) on average, with larger spikes in places, and winds flipped direction, changing by nearly 100 meters per second (200 miles per hour). That change influenced weather patterns lower in the atmosphere. These images and the associated animation show how the stratosphere changed and help illustrate why the United States and Europe were in the grip of such odd weather. The globes show temperatures (top) and vorticity (bottom) on January 10 (left) and February 2 (right). (The animation runs from January 10-February 4.) The images are based on assimilated weather observations of the atmosphere from the Goddard Modeling and Assimilation Office at NASA Goddard Space Flight Center.

    In the winter, little to no sunlight reaches Earth’s northern extremes. Deprived of energy, the stratosphere over the Arctic grows cold. These were the conditions present on January 10, 2009, as shown in the top left image. The cold air mass creates a low-pressure system in the stratosphere that sits over the Arctic throughout the winter. Farther south, where the Sun is shining, the air is warmer and air pressure is higher in the stratosphere. Air flows away from the high-pressure system towards the low-pressure system. Because the Earth is turning, the air is deflected to the right as it moves north, creating a strong counterclockwise (west to east) current of wind, which scientists call the polar night jet.

    The lower pair of images represent the air mass, or polar vortex, that controls the wind pattern. Essentially, the winds are strongest at the edge of the polar vortex (where the pressure difference between the air masses is greatest). The area of red in the lower left image represents polar air that typically sits over the Arctic during January. In general, strong winds circle the red regions, or areas of high vorticity, in a counterclockwise direction. These winds, moving at speeds well above 100 miles per hour, influence winds and weather patterns closer to Earth’s surface. Their influence means that weather in England and Western Europe typically comes from the west. Over England, western winds blow in ocean air warmed by the Atlantic Gulf Stream.

    The big change in the Arctic came when the polar vortex ripped apart. A developing weather system in the lower atmosphere traveled upward into the stratosphere. The disturbance nudged into the center of the Arctic air mass, elongating it and eventually splitting it like a cell in mitosis. By February 2, two air masses existed, each with a jet of wind circling it counterclockwise as depicted in the lower right image.

    Warm air filled the gap between the two colder air masses, and temperatures high over the North Pole climbed, as shown in the upper right. Now the colder air had shifted farther south over Canada and Siberia. Over North America, this piece of the stratospheric polar vortex had a deep reach into the lower atmosphere (troposphere), which created strong winds from the north that carried cold Arctic air far south into the United States.

    In Europe, the split in the air mass actually changed the direction of winds in the lower atmosphere. The second piece of the polar vortex was centered east of Western Europe, as shown in the lower left image, and it too was surrounded by a jet of strong wind moving counterclockwise. Like the segment of the polar vortex over North America, this piece of the polar vortex also had a deep reach into the lower atmosphere. It caused cold continental air to blow in from the east, replacing the warmer air that typically blows in from the west. As the frigid air moved over the North Sea, it picked up moisture, which fell over the United Kingdom and parts of France as heavy snow.”
    http://earthobservatory.nasa.gov/IOTD/view.php?id=36972

    Stratospheric Temperature

    NASA – Click the pic to view at source

    Stratospheric Vorticity

    NASA – Click the pic to view at source

    Animation of Stratospheric Vorticity:
    http://eoimages.gsfc.nasa.gov/images/imagerecords/36000/36972/npole_gmao_200901-02.mov

  62. ren says:

    We must also observe the stratosphere over the South Pole. Worth seeing had happened there in the winter. AAO from August fell to record levels by the end  of winter. In animation you can see the waves reach the upper stratosphere.
    http://www.cpc.ncep.noaa.gov/products/intraseasonal/temp10anim.gif

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