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Antarctic Sea Ice Extent


Snow_Miser

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All of the down-players come out of the woodwork. It's not relevant to you so don't involved. Not sure what the exact signal is. I believe it is a PV contraction that signals an abrupt process. It does make sense considering July 2015 was the warmest month ever.

Not sure what the first part of your garbled remark means.

And NCEP says that July 2015 was not the warmest month ever.

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All of the down-players come out of the woodwork. It's not relevant to you so don't involved. Not sure what the exact signal is. I believe it is a PV contraction that signals an abrupt process. It does make sense considering July 2015 was the warmest month ever.

Don't backtrack now! You made a foolish post because the sea ice dropped...finally... after the insane record levels of the last few years & you scream "abrupt climate change". You were called out.

Massive growth occurs & the sea ice is back above normal & it makes that post look as stupid as it really was. #HYPEMASTER

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Don't backtrack now! You made a foolish post because the sea ice dropped...finally... after the insane record levels of the last few years & you scream "abrupt climate change". You were called out.

Massive growth occurs & the sea ice is back above normal & it makes that post look as stupid as it really was. #HYPEMASTER

Large changes in the Antarctic sea ice probably does signal something out of the ordinary. I don't think his original post was foolish. There is plenty of evidence to suggest that the abnormally high extent over the past two years could very easily be from climate change. When we saw the extent anomaly plunge it really does make you wonder why. Can you explain why? Don't you agree it could easily be a feedback from a climate change induced weather pattern we have been seeing? Im sure someone will chime in and say well how can climate change cause growth and regression of the ice. It can and these developments could very well be a signal that something big is underway.

Your post was very derogatory and dismissive. That's a sure fire way to end up with egg on your face. Once you think you have our delicate climate system figured out it has a way of humbling even the most certain of opinions.

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Large changes in the Antarctic sea ice probably does signal something out of the ordinary. I don't think his original post was foolish. There is plenty of evidence to suggest that the abnormally high extent over the past two years could very easily be from climate change. When we saw the extent anomaly plunge it really does make you wonder why. Can you explain why? Don't you agree it could easily be a feedback from a climate change induced weather pattern we have been seeing? Im sure someone will chime in and say well how can climate change cause growth and regression of the ice. It can and these developments could very well be a signal that something big is underway.

Wind patterns. Easy to see how Antarctic sea ice extent tracks closely with the SAM index. Definitely no "abrupt climate change" involved, at least as of now.

The wind patterns associated with the strengthening PV/SAM down there are responsible for cooling the Southern Ocean and increasing sea ice extent.

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Wind patterns. Easy to see how Antarctic sea ice extent tracks closely with the SAM index. Definitely no "abrupt climate change" involved, at least as of now.

The wind patterns associated with the strengthening PV/SAM down there are responsible for cooling the Southern Ocean and increasing sea ice extent.

Do you think those wind patterns are associated with climate change? My answer would be it's possible. Climate change will increase extreme weather events. It is nearly impossible to attribute CC to specific event, but those events will increase in frequency.

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Do you think those wind patterns are associated with climate change? My answer would be it's possible. Climate change will increase extreme weather events. It is nearly impossible to attribute CC to specific event, but those events will increase in frequency.

It's possible, but most of the literature blames increasing O^3 depletion for the stronger PV/SAM. The depletion of O^3 has resulted from a combination of both anthropogenic CFC emissions, and a weakening planetary magnetic field.

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Do you think those wind patterns are associated with climate change? My answer would be it's possible. Climate change will increase extreme weather events. It is nearly impossible to attribute CC to specific event, but those events will increase in frequency.

But now you're saying both things are caused by climate change. When the Antarctic ice goes up, it's climate change. When the Antarctic ice goes down, it's climate change.

 

Convenient way to always win an argument. Unfortunately you can't have your cake and eat it too. Sort of like when we had those snowless winters in the 90s, it was global warming. Then we got a lot of snow in 09-10, 10-11, 13-14, and it was, again,  global warming. So it literally doesn't matter what the outcome is, certain players will claim it is climate change no matter what directon the data goes.

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But now you're saying both things are caused by climate change. When the Antarctic ice goes up, it's climate change. When the Antarctic ice goes down, it's climate change.

Convenient way to always win an argument. Unfortunately you can't have your cake and eat it too. Sort of like when we had those snowless winters in the 90s, it was global warming. Then we got a lot of snow in 09-10, 10-11, 13-14, and it was, again, global warming. So it literally doesn't matter what the outcome is, certain players will claim it is climate change no matter what directon the data goes.

Climate change will cause more extremes, those extremes can come in all forms. It's not a far fetched concept. Attribution of a single event to climate change is nearly impossible to do. Attribution to a general increase in extreme events, all kinds of events can be.
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But now you're saying both things are caused by climate change. When the Antarctic ice goes up, it's climate change. When the Antarctic ice goes down, it's climate change.

 

Convenient way to always win an argument. Unfortunately you can't have your cake and eat it too. Sort of like when we had those snowless winters in the 90s, it was global warming. Then we got a lot of snow in 09-10, 10-11, 13-14, and it was, again,  global warming. So it literally doesn't matter what the outcome is, certain players will claim it is climate change no matter what directon the data goes.

 

Well his claim was "CC will increase extreme weather events"....this is the statement to focus on. The assertion in this form is quite vague though. What extreme events are we talking about? CC increases some extreme events while it decreases others...and the spatial variability is high in where this occurs. I assume he meant that it increases the variability of the circumpolar winds around Antarctica. I haven't seen anything to back up that assertion. I have seen papers that say CC may have contributed to the recent tightening of the circumpolar vortex over the southern polar region....but it doesn't mean that the year to year variability has become greater. Perhaps there are papers that show this, but I haven't seen them.

 

On the other hand, the argument you are talking about is what I commonly refer to as "the butterfly effect argument"....meaning some people will just tell you that CC affects everything so every bit of weather we experience is due to CC. While that is technically true, it is really a useless piece of information. We are more concerned if CC affects the frequency and magnitude of weather events. CC may cause a snowstorm in Boston on February 3rd but it prevented one from occurring on February 7th, so the net change was zero. So if the net change was zero, then CC does not affect the frequency.

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The primary reason for the variation in the southern hemispheric sea ice anomaly appears to be stratospheric ozone modulation of the tropospheric mid-latitude jet, that is, the Southern Annular Mode. Ozone depletion over recent decades has induced changes in the SAM which have allowed for increased ice growth.

 

http://onlinelibrary.wiley.com/doi/10.1002/qj.2330/abstract

 

 

"We review what is presently known about the climate system response to stratospheric ozone depletion and its projected recovery, focusing on the responses of the atmosphere, ocean and cryosphere. Compared with well-mixed greenhouse gases (GHGs), the radiative forcing of climate due to observed stratospheric ozone loss is very small: in spite of this, recent trends in stratospheric ozone have caused profound changes in the Southern Hemisphere (SH) climate system, primarily by altering the tropospheric midlatitude jet, which is commonly described as a change in the Southern Annular Mode. Ozone depletion in the late twentieth century was the primary driver of the observed poleward shift of the jet during summer, which has been linked to changes in tropospheric and surface temperatures, clouds and cloud radiative effects, and precipitation at both middle and low latitudes. It is emphasized, however, that not all aspects of the SH climate response to stratospheric ozone forcing can be understood in terms of changes in the midlatitude jet. The response of the Southern Ocean and sea ice to ozone depletion is currently a matter of debate. For the former, the debate is centred on the role of ocean eddies in possibly opposing wind-driven changes in the mean circulation. For the latter, the issue is reconciling the observed expansion of Antarctic sea-ice extent during the satellite era with robust modelling evidence that the ice should melt as a result of stratospheric ozone depletion (and increases in GHGs). Despite lingering uncertainties, it has become clear that ozone depletion has been instrumental in driving SH climate change in recent decades. Similarly, ozone recovery will figure prominently in future climate change, with its impacts expected to largely cancel the impacts of increasing GHGs during the next half-century."

 

 

 

Papers have proposed different mechanisms by which stratospheric ozone is impacted. Some papers ascribe much of the ozone variation to changes in solar activity, and as the following study demonstrates, galactic cosmic rays:

 

http://www.sciencedirect.com/science/article/pii/S1364682612000867

 

 

 

"The strong sensitivity of the Earth's radiation balance to variations in the lower stratospheric ozone—reported previously—is analysed here by the use of non-linear statistical methods. Our non-linear model of the land air temperature (T)—driven by the measured Arosa total ozone (TOZ)—explains 75% of total variability of Earth's T variations during the period 1926–2011. We have analysed also the factors which could influence the TOZ variability and found that the strongest impact belongs to the multi-decadal variations of galactic cosmic rays. Constructing a statistical model of the ozone variability, we have been able to predict the tendency in the land air T evolution till the end of the current decade. Results show that Earth is facing a weak cooling of the surface T by 0.05–0.25 K (depending on the ozone model) until the end of the current solar cycle. A new mechanism for O3 influence on climate is proposed."

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Don't backtrack now! You made a foolish post because the sea ice dropped...finally... after the insane record levels of the last few years & you scream "abrupt climate change". You were called out.

Massive growth occurs & the sea ice is back above normal & it makes that post look as stupid as it really was. #HYPEMASTER

:clap:

 

Large changes in the Antarctic sea ice probably does signal something out of the ordinary. I don't think his original post was foolish. There is plenty of evidence to suggest that the abnormally high extent over the past two years could very easily be from climate change. When we saw the extent anomaly plunge it really does make you wonder why. Can you explain why? Don't you agree it could easily be a feedback from a climate change induced weather pattern we have been seeing? Im sure someone will chime in and say well how can climate change cause growth and regression of the ice. It can and these developments could very well be a signal that something big is underway.

Your post was very derogatory and dismissive. That's a sure fire way to end up with egg on your face. Once you think you have our delicate climate system figured out it has a way of humbling even the most certain of opinions.

You have to be joking you're seriusely going to support that silly post that he made.  Common sense would say it's weather variability.

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You have to be joking you're seriusely going to support that silly post that he made. Common sense would say it's weather variability.

Common sense to me says you can't be sure about why it happened. I fully admit it could be weather variability. I also don't think you can rule out CC. BTW CC includes ozone depletion (part of that can be directly attributed to man btw) Your side tends to attribute everything under the sun to variability. There is a gray area I think most folks (seemingly you as well) miss.
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I would consider my school of thought to reside in the interplay between natural variability and AGW. The ratio is a bit more skewed towards AGW now but one must consider SAM fluctuations.

 

Seeing large variations like occured in Winter/Spring 2015 (Southern Hemisphere) does strike my interest, anything that is unprecedented is worth monitoring considering our emergent risk assessment view. I will remain concerned until global temperatures level off again. We were already close to tipping points so an additional 0.2C or so may be enough to set something off.

 

Additionally, aerosols will be decreasing over the coming decades, lifting the cooling mask/Faustian bargain. We live in sensitive and exponential times.

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Common sense to me says you can't be sure about why it happened. I fully admit it could be weather variability. I also don't think you can rule out CC. BTW CC includes ozone depletion (part of that can be directly attributed to man btw) Your side tends to attribute everything under the sun to variability. There is a gray area I think most folks (seemingly you as well) miss.

Did something unprecedented happen that i am missing?  All i see is SIA diverged from it's steady rise because of weather conditions either by temps or wind patterns or a combination of both.  The main point of my post was to show weatherguy how silly his statement was in hopes that he might think alittle more before posting.  Are we expected to not see changes like this to happen?   Nothing is static when it comes to weather.  Just looking at the SIA chart you can see plenty of weather variability in years with lots of ups and downs around this time of the year. 

 

Since it's almost impossible to atribute a single event to CC i like to stick with historical records and basing something off of that to come to a conclusion.  By the way you posted this reply to Gawx post last year in this thread so it sounds like we're basically on the same page.

 

 

  It is even more amazing to me considering the warming globe as a whole. AGW alarmists often try to tie practically everything to AGW and it often sounds silly and makes them seem nonobjective. I think some are connecting this to it, too. If so, how are they connected? What would be the mechanisms? Or is it really due to colder temperatures? Even if it really were tied to AGW, then wouldn't the increased ice later lead to higher Antarctic albedo and then to colder/negative feedback down there?

 

 

I think that connecting the record high extent to AGW is a mistake.  There are more than enough events you can strongly tie to AGW to not have to resort to trying to connect the dots here when either there isn't a connection or we just don't know enough about what is going on to come to that conclusion.  Perhaps in the future when we have a better understanding of decadal cycles we could one day say with confidence the reason behind what is happening in Antarctica. 

 

The AGW alarmists aren't helping and the deniers aren't helping either.  I respect opinions that fall in the middle, the rest are thrown into the trash heap.

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The only problem with the GaWx perspective is that Antarctcia SIE has returned to a near-normal state and would not contribute much of an albedo forcing. Even bloggers like Robert Scribbler wrote up lengthy posts last year about how this expansion could dampen global warming, but this mindset does fall into the Hansen meltwater school of thought and is still a valid outlook.

 

My biggest complaint to date is the lack of more efficient measuring of meltwater discharge from Antarctica. GRACE is decent but not enough for real-time study.

 

Why the sudden shift in SIE? It's not like it was a gradually tapering back to normal. That is all for now, good honest questions with no answers.

 

If Southern Hemisphere inter-annual circulation variations are that intense, Antarctica SIE expansion is pretty much a non-issue and a poor scientifically-untenable reason to deny AGW. Furthermore, evidence points towards melt water/salinity decrease and increasing wind speeds, which are according to the latest literature driven by AGW and/or Ozone depletion.

 

So if melt water from Antarctica is not decreasing and is possibly increasing, what kind of forcing does one need to overpower the SIE formation signal so quickly? Must be one heck of a shift somewhere in the system.

 

That is the general logic behind the abrupt climate change signal.

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Here is a quote from NSIDC for July.

July average extent for Antarctica was 17.06 million square kilometers (6.59 million square miles). Sea ice extent grew at approximately 150,000 square kilometers per day (58,000 square miles per day) for the first half of July, but then growth slowed to just 10,000 square kilometers (3,900 square miles) per day for much of the rest of the month. The change was due to regional ice retreats in the northern Weddell Sea and northwestern Ross Sea,  almost balanced by continued growth in the northern Bellingshausen Sea west of the Antarctic Peninsula. The slower growth in sea ice extent places 2015 now at around 4th highest in terms of daily extent, below 2014, 2013, and 2010.

Relatively warm conditions prevailed for much of the month in the two regions of ice edge retreat, the northern Weddell Sea and northwestern Ross Sea, with average air temperatures at the 925 hPa level (3,000 feet above sea level) at approximately 4 degrees Celsius (7 degrees Fahrenheit) above average. However, sea surface temperatures just north of the ice edge were 0.5 to 1 degree Celsius (1 to 2 degrees Fahrenheit) cooler than average, raising the potential for rapid ice growth through the remainder of the winter season.

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There is definitely no abruptly climate shift.

Half the ice is a meter thick.

And the areas that expand and contract fast probably half meter at best.

Also the ice down there is Pancake ice.

It's not a flat sheet like the arctic becomes in late Spring.

Make no mistake, it's coming sooner than later my man if we don't get our act together.

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Make no mistake, the Antarctic is pretty cold right now my man.

It is winter down there right now so yes it's cold. It has however been above average the last week and the last month. Actually some pretty large areas of above normal temps down there.

The + anomalies have been covering the land ice, which could arguably be stated as much more important than colder anomolies over water.

post-2727-0-23487900-1441933647_thumb.jp

post-2727-0-41549400-1441933658_thumb.jp

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https://news.vice.com/article/just-because-antarctica-might-be-gaining-ice-doesnt-mean-climate-change-isnt-happening

Clever study but it falls short of its intended purpose. Many flaws are visible in the methodology. Here are some of my quotes from reddit. In hindsight, 2007-2008 was a key juncture in which polar health began to rapidly deteriorate in both hemispheres.

 

 

[–]OceanicEstate 1 point

2 hours ago  

The period of the study ends in 2008, alot has changed since. Studies like the above are inconvenient distractions during a time of needed urgency.

 

Perhaps eventually we will figure out why the acceleration occured, probably SMOC/AMOC interaction with a very potent -NAO/+AMO phase. These features in conjunction with the radiative forcing of AGW was enough to send WAIS into irreversible retreat in just 5 years.

 

 

[–]Deku__ 2 points

an hour ago  

So it's gaining in the interior but losing on the edges, and this is more or less balanced. Is that not a prediction of warming? More evaporation at lower latitudes and more precipitation in the interior, thickening the ice?

 

 
 

[–]OceanicEstate 1 point

22 minutes ago *  

Glacial melt on WAIS has increased since 2008 according to GRACE, and we don't know if snowfall accumulation has decreased or increased since 2008.

Furthermore, the study does not measure mass balance the same way that GRACE does. These differences must be reconciled before this study can be accepted as fact or relevant to future outcomes.

 

 
 

[–]OceanicEstate 1 point

12 minutes ago *  

GRACE Time Series antarctic_ice_mass_changes_nasa_jpl.jpg

20140124-Antarctica-GRACE-ice-mass-balan

 

 

clip_image0022.jpg

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