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Antarctic Sea Ice Extent


Snow_Miser

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The "record setting ice" in Antarctica at it's max is approximately ~1.2 million sq kilometers over the mean.  At the same token, the record low sea ice in the arctic was ~4 million sq kilometers under it's mean.  The trend on antarctic sea ice over the sat record is statistical insignificant.  When there is significance to the trend, scientists may pay more attention, but unfortunately, this is considered "noise" at this point and nothing more.  As you can see below (record in 2013), it's not a terribly compelling story yet (the orange line is the mean).

 

 

S_bm_extent.png

 

Is that orange line 1980-2010 average? That would be figuring the last 15 years of upward ice trend into the average.

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Exactly as I assumed, NFLs map was using 1980-2010, which would be heavily biased toward more average ice than historically present.

 

The arctic.... was barely an issue until just 8 years ago, it was going downward, but really dropped recently . I'm seeing a more consistent trend than the potentially spurious arctic.

 

arc_antarc_1979_2012.png

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In the middle of the cold season, it's really not.  If anything, the colder it is, the more dry it is and the less mass is added to the ice sheet.

 

That ice mass is millions of years old... Its a slow process either way. You could turn the temp up 15 degrees down there ( which it hasn't ) and it would take a few thousand years to melt... We will hit the next milankovitch cycle before then

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Still I beg to differ.  If we continue to see record setting cold in parts of the globe during this warm phase, what is going to happen when the AMO goes negative?

 

Remember, some of these posters don't believe in the AMO, they think its a symptom, not a cause.

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Still I beg to differ.  If we continue to see record setting cold in parts of the globe during this warm phase, what is going to happen when the AMO goes negative?

Probably very little actually.  It could change some regional weather, but it's hard to see a signature on ice.

 

http://agwobserver.wordpress.com/2010/12/16/papers-on-atlantic-multidecadal-oscillation-and-climate/

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Exactly as I assumed, NFLs map was using 1980-2010, which would be heavily biased toward more average ice than historically present.

 

The arctic.... was barely an issue until just 8 years ago, it was going downward, but really dropped recently . I'm seeing a more consistent trend than the potentially spurious arctic.

 

arc_antarc_1979_2012.png

Jonger, thanks for posting this.  This is a prime example of lack of context.  A standard deviation in the arctic over the past 35 years is nearly triple that of a standard deviation in the antarctic.  Meaning, in terms of area, the arctic trend is 3 times more amplified as compared to what that graph shows.

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  • 2 months later...

Is there a chance that the below normal solar has somehow already begun manifesting itself in the record high Antarctic ice and cooler southern hem. overall while still not having much effect in the northern hem.? Would there be a mechanism to somehow allow for this? Could the northern hem. be next? This is just food for thought to try to at least generate discussion.

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I'm not sure if it was the entire antarctic continent, but if the record cold was true... This is 1.2mil sq kilometers of additional ice and the land inside the continent that was below normal... adding those together, its a massive area and a significant event.

 

 

The only significant event for many is on the warm side.  Let's be honest....if this were a record minimum it would be all over the national news & those on this forum making light of this would be posting machines about the devastating consequences of this.  Guys...let's be a little more objective about data.  This really is a significant event.  The implications are certainly unknown but it's certainly a big deal.

 

I guess one could say that the glacial melt in the Western Peninsula & the warming going on there is really not a big deal also....NO!! Surely we all know better than that.  At the same time let's not make light of growing sea ice extent.  Remember, Antarctic Sea Ice extent at it's minimum was the greatest extent on record for a minimum.  Less melt in the summer is a big deal also. I'm not saying it means "this" or means "that" anymore than I'd say W. Peninsula warming means "this" or "that".

 

Let's also remember that while a million reasons have been blamed on the "hiatus" there have also been many reasons blamed on the Antarctic Sea Ice extent also.  We know that can't all be true.  I think the best road was taken by the IPCC AR-5 report when it states:

 

"There is low confidence in the scientific understanding of the observed increase in Antarctic sea ice extent since 1979, due to the incomplete and competing scientific explanations for the causes of change and lowconfidence in estimates of internal variability." (AR5 Chapter 10)

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Truly epic and unprecedented in our time.  This is an amazing sight to watch unfold, records keep getting shattered.  Amazing stuff.

 

  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?

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  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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I think the best road was taken by the IPCC AR-5 report when it states:

 

"There is low confidence in the scientific understanding of the observed increase in Antarctic sea ice extent since 1979, due to the incomplete and competing scientific explanations for the causes of change and lowconfidence in estimates of internal variability." (AR5 Chapter 10)

I agree with regard to this explanation. To date, there are varying explanations and hypotheses for the expansion of Antarctic sea ice extent and none is really conclusive. Such explanations range from a shift in stratospheric winds from the ozone hole to increasing fresh water concentrations around Antarctica on account of warming in part of the continent.

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I agree with regard to this explanation. To date, there are varying explanations and hypotheses for the expansion of Antarctic sea ice extent and none is really conclusive. Such explanations range from a shift in stratospheric winds from the ozone hole to increasing fresh water concentrations around Antarctica on account of warming in part of the continent.

 

This one seems hard to believe, considering the peripheral ice growth is probably several thousand miles from shore in spots.

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This one seems hard to believe, considering the peripheral ice growth is probably several thousand miles from shore in spots.

I'm just noting what some studies suggest. I believe the IPCC statement is probably the best approach as no study is really conclusive at this point. There are probably a number of factors contributing, but understanding at this time is quite poor.

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I think the best road was taken by the IPCC AR-5 report when it states:

 

"There is low confidence in the scientific understanding of the observed increase in Antarctic sea ice extent since 1979, due to the incomplete and competing scientific explanations for the causes of change and lowconfidence in estimates of internal variability." (AR5 Chapter 10)

 

This applies to much of climate science. There are often incomplete and competing explanations for things, and there also is a lack of knowledge about the internal variability of the climate system and the mechanisms behind different variables.

 

Doesn't mean we don't have a good grasp on some things, of course, but there is so much more still to be learned.

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I'm just noting what some studies suggest. I believe the IPCC statement is probably the best approach as no study is really conclusive at this point. There are probably a number of factors contributing, but understanding at this time is quite poor.

 

 

It probably has something to do with wind patterns changing.  The Southern Ocean has seem a huge up swing in OHC in the deeper levels.

 

OHC-AtlanticdrivesOHCvariation-Chen_zps3

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