Jump to content
  • Member Statistics

    17,597
    Total Members
    7,904
    Most Online
    DAinDC
    Newest Member
    DAinDC
    Joined

Arctic Sea Ice Extent, Area, and Volume


ORH_wxman
 Share

Recommended Posts

CT SIA has locked in 2nd place now...it fell below the 2011/2007 mins today. It would need another 600k or so to catch 2012, which isn't happening. (though I should never say never when it comes to these things...but it would be crazy to have that much loss this late in area...esp with that big area of low concentration near the pole which will likely refreeze pretty soon and be a headwind on further area losses after the next few days) Looks like extent though is lagging somewhat. Still uncertain whether we will make it for top 3 in extent.

 

I wonder if that poster last page still thinks my prediction range of 2nd-7th is still too low?

Link to comment
Share on other sites

New record sea ice minimums seem to take longer to achieve than most people expect. I can remember the articles calling for an ice

free Arctic by 2013 after the record low set in 2007. That record held on for 5 more seasons... longer than it was thought at the time.

And after the record was finally broken in 2012, it is still holding on 4 years later despite renewed calls by some for an ice free Arctic

by 2015 or 2016. So it will be interesting to see how long it actually takes to get to 1 million sq km or lower on NSIDC. Then the

discussion would probably go to how long to zero. That may take a while due to compaction of the remaining sea ice

up against the Canadian Archipelago and Greenland.

Link to comment
Share on other sites

1 minute ago, bluewave said:

New record sea ice minimums seem to take longer to achieve than most people expect. I can remember the articles calling for an ice

free Arctic by 2013 after the record low set in 2007. That record held on for 5 more seasons longer than it was thought at the time.

And after the record was finally broken in 2012, it is still holding on 4 years later despite renewed calls by some for an ice free Arctic

by 2015 or 2016. So it will be interesting to see how long it actually takes to get to 1 million sq km or lower on NSIDC. Then the

discussion would probably go to how long to zero. that may take a while due to compaction of the remaining compaction of

sea ice up against the Canadian Archipelago and Greenland.

 

We really need winter to warm a lot more to start really thinking about "ice free" (which is less than 1 million sq km).

 

Right now, the low sea ice in the autumn actually acts a negative feedback for volume regeneration in winter once we lose the sun. That open water sheds the excess heat pretty effectively and most of the volume gain occurs in the first couple months of refreeze, and then tails off as ice reaches the asymptotic point for thickness gain. Throw in a couple decent patterns in the winter (like we saw in 2012-2013 and then again in 2013-2014), and you end up "regressing" away from the ice free arctic and have decent volume bounces like we saw those years which means you have to "start over again" in trying to shed that volume. The last two years have trended back downward and lost back that volume gain, but they can reverse with a decent winter pattern and a non-dipole summer.

 

I forget where I read this...I'll look around...but someone had shown that we really need winter to warm about another 2C to really be able to get ice free arctic. If everything happened perfectly in one season (abnormally warm winter coming off a bad melt season...then another horrendous pattern in melt season), we could maybe achieve it within a decade? Hard to say, but we want to see winters warm enough to where we aren't realizing the full regeneration of volume from first year ice.

Link to comment
Share on other sites

4 hours ago, ORH_wxman said:

CT SIA has locked in 2nd place now...it fell below the 2011/2007 mins today. It would need another 600k or so to catch 2012, which isn't happening. (though I should never say never when it comes to these things...but it would be crazy to have that much loss this late in area...esp with that big area of low concentration near the pole which will likely refreeze pretty soon and be a headwind on further area losses after the next few days) Looks like extent though is lagging somewhat. Still uncertain whether we will make it for top 3 in extent.

 

I wonder if that poster last page still thinks my prediction range of 2nd-7th is still too low?

Down 360k in the past 3 days.  With this late area drop, looks like 2016 is going to separate from 2011/2007 on CT SIA.

Link to comment
Share on other sites

21 hours ago, ORH_wxman said:

 

We really need winter to warm a lot more to start really thinking about "ice free" (which is less than 1 million sq km).

 

Right now, the low sea ice in the autumn actually acts a negative feedback for volume regeneration in winter once we lose the sun. That open water sheds the excess heat pretty effectively and most of the volume gain occurs in the first couple months of refreeze, and then tails off as ice reaches the asymptotic point for thickness gain. Throw in a couple decent patterns in the winter (like we saw in 2012-2013 and then again in 2013-2014), and you end up "regressing" away from the ice free arctic and have decent volume bounces like we saw those years which means you have to "start over again" in trying to shed that volume. The last two years have trended back downward and lost back that volume gain, but they can reverse with a decent winter pattern and a non-dipole summer.

 

I forget where I read this...I'll look around...but someone had shown that we really need winter to warm about another 2C to really be able to get ice free arctic. If everything happened perfectly in one season (abnormally warm winter coming off a bad melt season...then another horrendous pattern in melt season), we could maybe achieve it within a decade? Hard to say, but we want to see winters warm enough to where we aren't realizing the full regeneration of volume from first year ice.

 

Cool season 80-90N has warmed by roughly 4C in the past 20 years, so unless things slow down, 2C is not that far away.

arcticwinterTncep.gif

Link to comment
Share on other sites

2 hours ago, chubbs said:

 

Cool season 80-90N has warmed by roughly 4C in the past 20 years, so unless things slow down, 2C is not that far away.

arcticwinterTncep.gif

What is the rate of cooling for the entire basin? 80N is really narrow region. It needs to cover the large region of where FYI regenerates volume. 

Link to comment
Share on other sites

1 hour ago, ORH_wxman said:

What is the rate of cooling for the entire basin? 80N is really narrow region. It needs to cover the large region of where FYI regenerates volume. 

Here is 70-80N on the Pacific side covering most of the rest of the Arctic Ocean. There are some year-to-year differences, particularly this year, but the overall trend is similar.

arcticwinterT70_80ncep.gif

Link to comment
Share on other sites

Definitely slower than the 80N graph tho. So I would guess that were still a good 20 years away from expecting regular ice free arctics at the min. Though the first occurrence would obviously happen sooner during a year when all the stars lined correctly. 

 

Though of course this is assuming that 2C figure I said earlier was correct and assuming the rate of warming did not increase or decrease....which is a lot of assumptions. 

Link to comment
Share on other sites

I think this year looks worse on the Pacific side assuming the whole ESS arm melts out. 2012 did have a "base" of multi-year ice still left on the PAC/Beaufort side of the CAB that was larger than this year's. Luckily in the winter of 2012-2013, that chunk got pushed westward and helped out with the rebound in 2013/2014 in volume when those summers were cold enough to keep that base of MYI in place.

 

Then 2015 came and melted out most of it in the Beaufort during the torch that summer...and this year, we're seeing the effects of that (along with a warm winter) with the ice melting out fairly easily on the PAC side despite avoiding a nasty dipole.

 

I am a bit surprised at how much ice survived in the Laptev sector given how the ice didn't hold out very well in the ESS....usually the ESS holds out better than the Laptev sector.

Link to comment
Share on other sites

NSIDC moves into second place ahead of 2007 but well behind 2012. That dramatic dipole reversal in June prevented us from equaling

or surpassing the 2012 record minimum. Impressive temperature spike at the pole with the steeper losses the last few days.

Screen shot 2016-08-30 at 11.56.44 AM.png

 

meanT_2016.png

 

Link to comment
Share on other sites

I asked this question on another thread but got no answer. Hope it is appropriate here.

If GW is mostly anthropogenic, then there is little doubt (actually no doubt) that the trend will continue. If it is only in small part anthropogenic, then can we assume it will continue at (or greater than) the current rate? Warm/cold multi-decadal fluctuations are common. 

My point is not to debate the obvious. The warming trend is measurable and beyond any serious contention. Since I have no idea how much of it is AG (5%,25%, 60%, 95%) and doubt anyone else can state how much is human caused with certainty, my question is purely just that. Do we have models that can give us a pretty clear idea that the overwhelming data points to continued, unabated GW? Or, is there room for longer term stasis or even cooling?

PS It seems certain that some of the warming is human related, so let's not go down that street and get into an argument over it. The question is about certainty. For the sake of argument, let's assume that AG contribution is <50%.

Link to comment
Share on other sites

17 minutes ago, J Paul Gordon said:

I asked this question on another thread but got no answer. Hope it is appropriate here.

If GW is mostly anthropogenic, then there is little doubt (actually no doubt) that the trend will continue. If it is only in small part anthropogenic, then can we assume it will continue at (or greater than) the current rate? Warm/cold multi-decadal fluctuations are common. 

My point is not to debate the obvious. The warming trend is measurable and beyond any serious contention. Since I have no idea how much of it is AG (5%,25%, 60%, 95%) and doubt anyone else can state how much is human caused with certainty, my question is purely just that. Do we have models that can give us a pretty clear idea that the overwhelming data points to continued, unabated GW? Or, is there room for longer term stasis or even cooling?

PS It seems certain that some of the warming is human related, so let's not go down that street and get into an argument over it. The question is about certainty. For the sake of argument, let's assume that AG contribution is <50%.

While science has not, and probably will not ever, precisely pin down GHG contribution. It is very likely between 75-125%. The earth would likely have cooled due to human aerosol pollution which is literally dimming the sun (this is why some areas with high levels of pollution have seen less warming). GHG warming has more than countered this cooling and created the observed warming. The sun has had a minimal effect since the sun has always had a minimal effect and is currently in a weak period of solar output.

We also know that every doubling of CO2 produces 1.1C of surface warming. The uncertainty is in the feed-backs, not CO2. The feed-backs are very likely positive. We should have seen .5C of warming based on CO2 alone without feedbacks. With feedbacks, probably .8-1.5C. The reason we have seen on the low end of that is aerosol pollution and the fact that the earth is still warming (even if we stopped emitting CO2 the earth would warm significantly more). 

Link to comment
Share on other sites

1 hour ago, skierinvermont said:

While science has not, and probably will not ever, precisely pin down GHG contribution. It is very likely between 75-125%. The earth would likely have cooled due to human aerosol pollution which is literally dimming the sun (this is why some areas with high levels of pollution have seen less warming). GHG warming has more than countered this cooling and created the observed warming. The sun has had a minimal effect since the sun has always had a minimal effect and is currently in a weak period of solar output.

We also know that every doubling of CO2 produces 1.1C of surface warming. The uncertainty is in the feed-backs, not CO2. The feed-backs are very likely positive. We should have seen .5C of warming based on CO2 alone without feedbacks. With feedbacks, probably .8-1.5C. The reason we have seen on the low end of that is aerosol pollution and the fact that the earth is still warming (even if we stopped emitting CO2 the earth would warm significantly more). 

Thank you. This helps. So, the good news (tongue in cheek) is that if we were to enter a larger scale cooling phase, AGW (GHG?) would compensate at least in part. A poor reason to foul the only nest we've got!

I'm perplexed as to why to politicians and political GW experts are focusing on wind power, solar power, etc. instead of putting massive funding into fusion power research and /or other hydrogen power sources. Low pollution factors and just about nil contribution to CO2.

Anyhow thanks again for a clear and understandable response

 

Link to comment
Share on other sites

how about the billions of tons of garbage dumped into our oceans the last 100 years or so ?  (mostly from commercial shippers that like to cut costs / save money)

Doubt anyone's factored that into the equation of our sea levels rising.

Like when u put ice into a glass of water...the water level rises..  yeah..kinda like that.

either way, it's sickening to me how much our oceans are polluted..and how people dump anything and everything into it.  There should be very serious laws implemented world-wide to stop this immediately.   Our oceans won't even be able to sustain life in 50 years or so...if this continues. 

Link to comment
Share on other sites

18 minutes ago, Bacon Strips said:

how about the billions of tons of garbage dumped into our oceans the last 100 years or so ?  (mostly from commercial shippers that like to cut costs / save money)

Doubt anyone's factored that into the equation of our sea levels rising.

Like when u put ice into a glass of water...the water level rises..  yeah..kinda like that.

either way, it's sickening to me how much our oceans are polluted..and how people dump anything and everything into it.  There should be very serious laws implemented world-wide to stop this immediately.   Our oceans won't even be able to sustain life in 50 years or so...if this continues. 

 

The trash is negligible to sea level rise. It takes 360 billion tons to raise SL by 1 millimeter...the total amount of trash is almost certainly less than that as the amount per year that ends up in oceans is usually measured in the low millions of tons.

Link to comment
Share on other sites

8 hours ago, ORH_wxman said:

 

The trash is negligible to sea level rise. It takes 360 billion tons to raise SL by 1 millimeter...the total amount of trash is almost certainly less than that as the amount per year that ends up in oceans is usually measured in the low millions of tons.

 

nice find, however you found that stat. 

still...millions of tons of trash a year, dumped into the ocean.  what happened to all the environmentalists that used to care about these things?   It's an extraordinary amount, that most people don't even assume.

another aspect (maybe u have a stat ) ,  is mammal reproduction.  Example, if we have a million more whales in the ocean next year, compared to this year....water volume = raised.   Then again, with our oceans getting more polluted every year...it could be helping to cut down on those numbers.  

silly humans, screwing everything up.

other mini-aspects that could mess with the numbers as well :  volcanoes / earthquakes .

Link to comment
Share on other sites

3 hours ago, Ufasuperstorm said:

 

Just in the above localized regions that is 50,841,530.054707594 gallons annually. (Try and imagine worldwide how much naturally seeps)

 

I don't even wanna know.  At-least our country reports it, most other countries hide it...and we don't do anything to penalize them.  But yea, that's another thing.  Oil leaks not properly sealed off.  It could be Exxon Valdez times a 1000 out there...and nobody knows.

Since it doesn't effect humans from breathing, everybody just looks the other way.  It does however effect ocean life from breathing.  

heck, even when Chernobyl happened...nobody even knew about it for days,  until radiation detectors in the next country over were off the charts.  Amazing the Russians tried to hide that.  Kursk too, I think they tried to hide.

guess maybe we shud make another topic, before going too OT here.  But I appreciate the insight.

 

Link to comment
Share on other sites

16 hours ago, J Paul Gordon said:

Thank you. This helps. So, the good news (tongue in cheek) is that if we were to enter a larger scale cooling phase, AGW (GHG?) would compensate at least in part. A poor reason to foul the only nest we've got!

I'm perplexed as to why to politicians and political GW experts are focusing on wind power, solar power, etc. instead of putting massive funding into fusion power research and /or other hydrogen power sources. Low pollution factors and just about nil contribution to CO2.

Anyhow thanks again for a clear and understandable response

 

Even if every other natural factor aligned for cooling we'd stay well above pre-industrial temperatures. The only exception would maybe be a temporary 5-10 year cold spell by a 1 in 10,000+ year volcanic eruption. 

Even if the earth's axis and orbit aligned for an ice age, we probably wouldn't cool very much if CO2 were pegged @400ppm. Much of the cooling in ice ages comes from a declining CO2 concentration feedback loop and without it, the cooling would be much less. It might just cause us to stop warming instead of continuing to warm. You have to understand that even if CO2 stopped rising, the earth is still gaining unimaginable quantities of thermal energy every second and surface temperatures would continue to rise for some decades (until surface temperatures are high enough that outgoing LW radiation is in balance with incoming SW radiation). 

But if the factors aligned strongly enough, we probably would see some cooling. But nothing like any ice age. I don't think there has ever been an ice age with CO2 at 400ppm.

Link to comment
Share on other sites

30 minutes ago, Bacon Strips said:

I don't even wanna know.  At-least our country reports it, most other countries hide it...and we don't do anything to penalize them.  But yea, that's another thing.  Oil leaks not properly sealed off.  It could be Exxon Valdez times a 1000 out there...and nobody knows.

Since it doesn't effect humans from breathing, everybody just looks the other way.  It does however effect ocean life from breathing.  

heck, even when Chernobyl happened...nobody even knew about it for days,  until radiation detectors in the next country over were off the charts.  Amazing the Russians tried to hide that.  Kursk too, I think they tried to hide.

guess maybe we shud make another topic, before going too OT here.  But I appreciate the insight.

 

I don't think you understood him. He's saying since so much oil seeps NATURALLY it doesn't matter when humans spill a few million gallons.

 

I'm not sure if he even read his own links though. The second one says that plastics take forever to degrade in the oceans and plastics building up in the ocean are major environmental problem...

Link to comment
Share on other sites

Now that August is ending, a closer look at the Arctic sea ice extent figure is in order.

The 8/30 figure (JAXA) was 4,302,421 square kilometers. If that were the minimum, it would rank as the 5th lowest on record.

However, it is all but certainly not the minimum. A number of scenarios for the minimum figure:

Smallest decline from 8/30 to the minimum (2002-15): 4,140,726 square kilometers (would rank 3rd lowest)

Largest decline from 8/30 to the minimum (2002-15): 3,793,311 square kilometers (would rank 2nd lowest)

Average decline from 8/30 to the minimum (2011-15): 4,007,579 square kilometers

All said it appears very likely that 2016 will see the 2nd or 3rd lowest Arctic sea ice extent minimum on record. There remains a reasonable possibility of a minimum figure below 4 million square kilometers for only the 2nd time on record (JAXA). 2012 is currently the only such case.

Link to comment
Share on other sites

4 hours ago, Ufasuperstorm said:

My initial post, was simply a counter argument to Bacon Strips unscientific statements. The second link clearly states:

 

 

However, later:

 

 

 

Perhaps we should check our reading comprehension next time, before making baseless accusations?

 

 

If you read the article, it says that an organism "exists" not that said organism is widespread or actually breaks down most plastics in nature. The idea is we could breed this organism and spray it all around the world to dissolve plastics.

This is easily proven by the fact that the oceans are full of plastic.

Link to comment
Share on other sites

4 hours ago, donsutherland1 said:

Now that August is ending, a closer look at the Arctic sea ice extent figure is in order.

The 8/30 figure (JAXA) was 4,302,421 square kilometers. If that were the minimum, it would rank as the 5th lowest on record.

However, it is all but certainly not the minimum. A number of scenarios for the minimum figure:

Smallest decline from 8/30 to the minimum (2002-15): 4,140,726 square kilometers (would rank 3rd lowest)

Largest decline from 8/30 to the minimum (2002-15): 3,793,311 square kilometers (would rank 2nd lowest)

Average decline from 8/30 to the minimum (2010-15): 4,007,579 square kilometers

All said it appears very likely that 2016 will see the 2nd or 3rd lowest Arctic sea ice extent minimum on record. There remains a reasonable possibility of a minimum figure below 4 million square kilometers for only the 2nd time on record (JAXA). 2012 is currently the only such case.

Would expect above average extent losses to close out the melt season due to the large areas of low concentration ice, good melting momentum, and relatively mild weather to start September particularly over the Laptev.

Link to comment
Share on other sites

2 minutes ago, chubbs said:

Would expect above average extent losses to close out the melt season due to the large areas of low concentration ice, good melting momentum, and relatively mild weather to start September particularly over the Laptev.

That's the way it appears. That's why I still think there's a reasonable prospect that the minimum will be under 4 million square kilometers.

Link to comment
Share on other sites

The 8/31 figure on JAXA was 4,242,650 square kilometers. That would rank as the 3rd lowest minimum figure on record. Only 2012 (3,177,455 square kilometers) and 2007 (4,065,739 square kilometers) were lower. The 5-year average decline in sea ice extent from 8/31 would produce a minimum figure of 3,979,208 square kilometers. The minimum decline (2002-15) would result in a figure of 4,092,669 square kilometers. The maximum decline (2002-15) would result in a minimum figure of 3,740,828 square kilometers.

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share

  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...