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Arctic Sea Ice Extent, Area, and Volume


ORH_wxman
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5 hours ago, WidreMann said:

To add to this, people are failing to grasp that AGW is about how humans are applying a small modulation to an existing system, and there are small changes, but they are very significant for life on earth. With CO2 at all, the planet would be some 50 degrees cooler, I believe. Raising it by 3 or 4 degrees, therefore, is not a big deal in terms of the numbers. But it is a big deal when it causes sea levels to rise and some land to be inundated. Again, it's not a lot of land. Most land will be fine. But we have a lot of cities on the coasts. That's a big deal for humans. When rising CO2 increases acidity levels in the ocean, it still may not be by much. But it's a lot for the life that lives there, that starts to die off when it can't handle the change in water chemistry.

What we are talking about is life's sensitivity to change, not about gigantic changes to the atmosphere (which we really aren't making). Life can handle change, but over larger time periods. When there are significant changes in a short time period, a lot of life dies off. Of course, in time, it will recover, as it did 65 million years ago, or during other extinction events. It's bad news for humans, though, because we depend on the ecosystem as it is. We can mitigate with technology or general inventiveness, but it will be a very big blow to our current civilization. That's why people should care. Not because the planet will explode (it won't). Not because one weird species of frog in outer Mongolia will go extinct (why should anyone care about that anyway?). Not because temperatures will go up  yby a billion degrees (they won't). It's because the small changes made to a climate that has been fairly stable for civilized human history have  b effects for life and human life, which is sensitive to small changes. What good is oil and profit if we can't eat, can't live where we used to? That's the trade-off.

I agree with a lot of what you are saying. AGW will not be a doomsday scenario like alarmist portray, however very significant changes will happen if we fail to reduce CO2 emissions to levels in the low 300ppm range. I think humans would be able to adapt to major warming, but I'm afraid many other species will not, which could cause major ecological issues. We shouldn't gamble with our relatively stable environment, 2-4 degrees C, could put extraordinary pressure on global food and fresh water supplies. If Greenland were to melt out, it would cause trillions of dollars to relocated massive amounts of people around the world further inland. Also you said we haven't seen massive changes to our atmospheric patterns, we might not have seen large changes yet, but if the arctic sea ice fully melts out, you will begin to see more extremes. 

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4 hours ago, CaWx said:

I agree with a lot of what you are saying. AGW will not be a doomsday scenario like alarmist portray, however very significant changes will happen if we fail to reduce CO2 emissions to levels in the low 300ppm range. I think humans would be able to adapt to major warming, but I'm afraid many other species will not, which could cause major ecological issues. We shouldn't gamble with our relatively stable environment, 2-4 degrees C, could put extraordinary pressure on global food and fresh water supplies. If Greenland were to melt out, it would cause trillions of dollars to relocated massive amounts of people around the world further inland. Also you said we haven't seen massive changes to our atmospheric patterns, we might not have seen large changes yet, but if the arcitic sea ice fully melts out, you will begin to see more extremes. 

Maybe the most alarming predictions won't come true, but even the middle of the road predictions are scary enough. Of course we will adapt, as will the rest of life. It just won't be pretty. There is enough suffering in the world as is.

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14 hours ago, Joe Vanni said:

I don't think we are going to get anywhere debating this when we are at the end of the global warming period, so you get the see the warm results of the past 36 years. I'm not debating that we have had great warmth, but I question the validity of saying the warmth is fastest on record. We are going to have to wait a few years when people actually see the cooling begin and that it has lasting power. We've been spoiled with this warmth but that's coming to an end. 

I've been listening to people like you say the cooling is coming for over 10 years. In fact, I had a radio show in college 10 years ago where I actually said we could see some cooling and AGW might be greatly exaggerated. Mostly I was overreacting to learning that some news articles, Al Gore, and even some science was skewed towards AGW and I went off too far in the other direction. I learned from my mistakes. Some never do.

 

We've already been through one very weak solar cycle for 10 years now. The earth didn't cool down. It didn't even stop warming.. it warmed a lot the last 10 years. This is where you introduce some magical lag period you read about on some internet blog that doesn't make any logical or physical sense. Let me tell you a secret.. these magical "lag" people were the same ones saying cooling was imminent 10-15 years ago. Then they invented the lag, because instead of the warming reversing or stopping, if anything it actually accelerated.

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13 hours ago, Silver Meteor said:

Good morning. Long time lurker here, one who prefers listening over talking but do of course appreciate the talkers without whom there would be no thread to begin with.

Science has always been "in my blood." It started with my grade school years (1950s) in Maryland with a fascination in the shape of continents which suggested they surely must have moved over time. This idea was proved to be true years later when I was in high school. Also in high school we were taught the "Big Bang Theory" and the "Theory of Global Warming" neither of which were controversial at the time (I'd never heard of such a thing as "creationism", and it would be many years before AGW became politicized.)

Over the ensuing decades I continued learning about and keeping up with science at my own pace, first from books then from the internet as it developed. Watching in real time the continuous fine tuning in a variety of subjects as these many years have passed has helped keep my interest alive and healthy. So, what about climate? Oh dear, where does one begin...

To avoid dragging this out I'll just say I remain comfortable with my paradigms, none of which are "catastrophic." The best empirical evidence I see for AGW is clearly that which is occurring in the Arctic. Meanwhile, down here in the Mid-Atlantic U.S. the only change of note over the last 60+ years has been our tremendous population growth with its accompanying water pollution and its greatly expanded road networks and heat islands. Overall, I accept AGW but to suggest this is our greatest problem for the future, is, in my opinion, utter nonsense; this reeks of political expedience for the financial gain of a few without regard to the many serious non-climate problems lying in wait, problems our media is loathe to discuss. Moreover it implies technology will not progress, a ludicrous proposition.

The good, the bad, and the ugly...

The good will be technological improvements with power generation; I see little reason to doubt fusion power plants will be up and running before mid-century. The bad is an historical analysis of currencies that suggests our fiat dollar will not survive to mid-Century (perhaps or even probably not even to 2040.) And the ugly is multicultural demographics which will lead to a Balkanization of the U.S., also before mid-Century (likely to coincide with the economic earthquake of currency collapse.) All of this I'm sure appears fanciful to those who don't study such subjects and believe "tomorrow will always be like yesterday and today", but for them history always provides the rudest of awakenings.

However much climate change we see before the widespread use of fusion power will pale in comparison to the socio-political changes that will have staggering effects in the coming decades. I won't be around to see it but eventually the dust will settle and mankind will march forward, wiser and safer into a bright 22nd Century (where technology will be fantastically more advanced than it is today.) What I will do is all I can do, and that is to continue watching, learning, and enjoying science as I always have. To the rest of you, good luck and keep up the good work!

 

 

I think your overall point has some validity. There are a lot of pressing problems facing humanity today. There could be even more in the future, regardless of climate change. But I would suggest reading some more scientific sources about the effects of climate change. Increases in flooding, drought, and sea level will have huge costs to humanity. It affects the entire planet and the problem is not temporary. 

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7 hours ago, skierinvermont said:

I've been listening to people like you say the cooling is coming for over 10 years. In fact, I had a radio show in college 10 years ago where I actually said we could see some cooling and AGW might be greatly exaggerated. Mostly I was overreacting to learning that some news articles, Al Gore, and even some science was skewed towards AGW and I went off too far in the other direction. I learned from my mistakes. Some never do.

 

We've already been through one very weak solar cycle for 10 years now. The earth didn't cool down. It didn't even stop warming.. it warmed a lot the last 10 years. This is where you introduce some magical lag period you read about on some internet blog that doesn't make any logical or physical sense. Let me tell you a secret.. these magical "lag" people were the same ones saying cooling was imminent 10-15 years ago. Then they invented the lag, because instead of the warming reversing or stopping, if anything it actually accelerated.

Well it seems they rushed it. The research and forecasters I've found to be most accurate at long ranges have stayed with the same story. But that's like me saying how some on the AGW side was claiming ice free Arctic in 2012, 2013, 2014 and so on. It's not going to happen anytime soon; and yes I know how's it's trended since 1979, the beginning of the global warming period. Or how the Atlantic hurricanes were only going to get worse after 2005's record season. They misjudged, but they have misjudged more than just the reason for melting ice and hurricanes.

I think the peak will happen during solar cycle 26/27 but it'll become much more obvious as we approach 25 that something has switched.  I can see why you would point out how we have warmed despite s super weak cycle. But there is actually a legit lag and a point needed to cross to see the real effects on a longer-term. But as I said before, debating this will get us nowhere. People are going to have to start seeing effects at their own house before they realize something is up. 

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4 hours ago, Joe Vanni said:

Well it seems they rushed it. The research and forecasters I've found to be most accurate at long ranges have stayed with the same story. But that's like me saying how some on the AGW side was claiming ice free Arctic in 2012, 2013, 2014 and so on. It's not going to happen anytime soon; and yes I know how's it's trended since 1979, the beginning of the global warming period. Or how the Atlantic hurricanes were only going to get worse after 2005's record season. They misjudged, but they have misjudged more than just the reason for melting ice and hurricanes.

I think the peak will happen during solar cycle 26/27 but it'll become much more obvious as we approach 25 that something has switched.  I can see why you would point out how we have warmed despite s super weak cycle. But there is actually a legit lag and a point needed to cross to see the real effects on a longer-term. But as I said before, debating this will get us nowhere. People are going to have to start seeing effects at their own house before they realize something is up. 

There is no significant lag to a change in solar forcing but luckily solar forcing doesn't change very much. Solar irradiance varies by 0.25 Watts per square meter from the peak to the bottom of a normal solar cycle. Despite  the current  weak solar cycle, the earth's energy imbalance due to GHG has stayed around 0.8 W per square meter. In addition GHG forcing is increasing by roughly 0.4 W per square meter per decade, so even a repeat of the Maunder minimum isn't going to have much impact on the warming trend.

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45 minutes ago, Sundog said:

Can any natural mechanism explain the dramatic increase increase in temperatures on land and in the oceans over the last few decades?

 

When you show me one that can, let me know. 

I think Internet is a small wave inside a bigger wave. 1995 was internet boom, and 97-98 was major Earth climate cycle shift, super El Nino etc. 

Technology with regards to climate impact has pretty much halted since the 1970s, why are global temperatures spiking so anomalously in the last 20 years? Seriously though, technology has flat lined (cars, houses, NASA, etc), the Earth is speeding up major now. I think there other factors at play, probably having do with government. 

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Solar Cycle, decadal Water oscillations, and probably even greenhouse emissions is very simplistic of view of the world, I think. There is expanded communication happening now on awesome levels and even our ability to view the universe is 10,000x greater than before. This is a point in human consciousness evolution that history doesn't really have a point of reference for, shifting into new energy fields, dream perception, or something... new  the Earth's warming is just a really measurable part of it. 

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2 hours ago, Sundog said:

Can any natural mechanism explain the dramatic increase increase in temperatures on land and in the oceans over the last few decades?

 

When you show me one that can, let me know. 

Regionally yes there have been quite the dramatic temp rises, as we all know the arctic for one has been the leader in the largest anomalies. One thing though that can really shake up the warming idea is a simple volcanic eruption in mid to high latitudes, though only temporary and very variable in when it will happen, but it just goes to show how sensitive the atmospheric changes can occur and how quickly they can take place. While the release of GHG pollutants and the up tick over the past 30-40 years can certainly make the argument with a nice increase in temps I feel there is something that is taking place that we are not quite catching onto. We may be in the midst of an amplification pattern that we have not experienced before. Anomalous PDO pattern another record setting ENSO, but the el nino pattern lasting for almost 3 years with not much return to a cooler la nina pattern after the el nino. We have seen quite the heat pump to the arctic since, as someone had pointed out, 2005 time frame when things really took a hit in the Arctic. Larger meridonial flow moisture increasing temps wont decrease if we have a higher moisture content. Im still unsure about the whole idea AGW I feel it has impacted somewhat but was just a trigger to cause other things happen in as we see it a shorter time span there are just too many variables and too many uncertainties that have yet to be figured to know for certain how things will play out in the near future. We should take actions to reverse our pollution for sure but we are too uncertain of the future and predictions are just predictions to give us a better idea.

 

Just thoughts from what I have gathered thus far.

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AGW should be treated as any other insurance scenario. Nobody expects their house to burn down but I bet almost everybody out there (and everyone with a mortgage) has home insurance against several highly unlikely scenarios. 

Now we're talking about our whole planet, the only place we can call home. It's just a little bit more important than a few walls made of wood and brick yet we are currently playing with matches in a home with no insurance. 

Even if the uncertainty level regarding AGW was much higher than what it is now, we should still be all doing every damned thing possible to stop any type of GHG emissions.

The risk of doing nothing is enormous. The gain even if AGW was not real is having a totally transformed energy economy with countless new jobs that will support it. 

 

There are literally no negatives. 

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17 minutes ago, Sundog said:

AGW should be treated as any other insurance scenario. Nobody expects their house to burn down but I bet almost everybody out there (and everyone with a mortgage) has home insurance against several highly unlikely scenarios. 

Now we're talking about our whole planet, the only place we can call home. It's just a little bit more important than a few walls made of wood and brick yet we are currently playing with matches in a home with no insurance. 

Even if the uncertainty level regarding AGW was much higher than what it is now, we should still be all doing every damned thing possible to stop any type of GHG emissions.

The risk of doing nothing is enormous. The gain even if AGW was not real is having a totally transformed energy economy with countless new jobs that will support it. 

 

There are literally no negatives. 

 

The hardest part of this is not here or in many 1st world countries that can have the opportunity to change their energy systems, its a matter of if they want to or not and then that just brings in political ideals and whether they will be able to make money off it or not. It is countries like India in particular as they are trying to become a foot hold in the world economy but do not quite have the means to sit there and give many of their citizens the basics of electricity and heating/cooling as needed. So many go to cheaper forms of energy such as oil and coal to help their needs and places like India easily rank 3rd in emissions in the global sense with China being number 2 and they have the worse emission laws out there they just do not seem to care at all. They even went as far as to say issues such as smog, which is known to be a human caused weather phenomena that happens from stagnation in the pattern, as a natural disaster. How can one sit there and say this occurs naturally when we know what its being caused by. So in esssence yes in thought it seems fairly simplified to change over to something clean but the reality is if regions are not willing to change many will also follow suit and hold the ideas of using fossil fuels.

 

We would need to be one of the leaders in this change but we are too far gone in politics for this to occur right now. I believe India is trying to take great leaps in fixing this and honestly if a developing country is able to accomplish such a feat there is no reason the developed countries can not produce. If you go around and ask many citizens of the developed countries a good majority would say a change needs to happen but yet we continuously put ourselves back in the hole in which we are trying to dig out of. It will happen it is just a matter of when. 

 

I think if we talk anymore about stuff like this we should open a thread or DM as we are straying away from arctic sea ice talk. 

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17 hours ago, skierinvermont said:

I've been listening to people like you say the cooling is coming for over 10 years. In fact, I had a radio show in college 10 years ago where I actually said we could see some cooling and AGW might be greatly exaggerated. Mostly I was overreacting to learning that some news articles, Al Gore, and even some science was skewed towards AGW and I went off too far in the other direction. I learned from my mistakes. Some never do.

 

We've already been through one very weak solar cycle for 10 years now. The earth didn't cool down. It didn't even stop warming.. it warmed a lot the last 10 years. This is where you introduce some magical lag period you read about on some internet blog that doesn't make any logical or physical sense. Let me tell you a secret.. these magical "lag" people were the same ones saying cooling was imminent 10-15 years ago. Then they invented the lag, because instead of the warming reversing or stopping, if anything it actually accelerated.

Didn't know you were a skeptic too at one point. I accepted the mainstream conclusions of the science, when it became abundantly clear that we were still warming, and there was no sign of any prospective cooling. Learning more about the subject didn't hurt either. It's been over 3 years since I recognized this.

There are no energy accumulation lags. Zero. It is like saying that a pot on a stove will continue to gain energy, even after the burner has been turned off. It makes no physical sense. So the continued upper ocean heat accumulation is totally inconsistent with reduced solar activity. It is just not causing current climate change. 

Getting back on topic, a pretty poor pattern for the Pacific side of the ice is on the way. The 12z ECMWF is advertising well above normal 850 hPa temperatures in the medium range and beyond for that region. Kind of surprised we still saw sizable losses over the last few days, despite cooler than normal 850 hPa temperatures. Unless recent losses have all come from the Hudson Bay. I think persistence type predictions of the sea ice minimum, like June melt ponding have the potential to be more inaccurate than usual this year. With the ice being so thin, it won't take as much to see sizable losses in the coming couple of months. 

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More uncertainty about the actual thickness this year due to the divergence between PIOMAS and CryoSat. NSIDC mentioned it in a recent discussion.

Data from the European Space Agency’s CryoSat-2 satellite indicate that this winter’s ice cover may be only slightly thinner than that observed at this time of year for the past four years. However, an ice-ocean model at the University of Washington (PIOMAS) that incorporates observed weather conditions suggests the volume of ice in the Arctic is unusually low.

6a0133f03a1e37970b01bb09818900970d-800wi.png.850e4402699ef754c6811c09204a1509.png

 

 

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6 hours ago, Snow_Miser said:

Didn't know you were a skeptic too at one point. I accepted the mainstream conclusions of the science, when it became abundantly clear that we were still warming, and there was no sign of any prospective cooling. Learning more about the subject didn't hurt either. It's been over 3 years since I recognized this.

There are no energy accumulation lags. Zero. It is like saying that a pot on a stove will continue to gain energy, even after the burner has been turned off. It makes no physical sense. So the continued upper ocean heat accumulation is totally inconsistent with reduced solar activity. It is just not causing current climate change. 

Getting back on topic, a pretty poor pattern for the Pacific side of the ice is on the way. The 12z ECMWF is advertising well above normal 850 hPa temperatures in the medium range and beyond for that region. Kind of surprised we still saw sizable losses over the last few days, despite cooler than normal 850 hPa temperatures. Unless recent losses have all come from the Hudson Bay. I think persistence type predictions of the sea ice minimum, like June melt ponding have the potential to be more inaccurate than usual this year. With the ice being so thin, it won't take as much to see sizable losses in the coming couple of months. 

I went through a skeptic phase too. I was in high school and I was naturally skeptical about all sorts of stuff, if only to be contrarian. I also didn't like the idea of winter going away. But the evidence became overwhelming and I jumped ship.

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21 minutes ago, ORH_wxman said:

The rapid regression of PIOMAS seems to suggest that it might have been a little low in May versus reality. Hard to say for sure. We'll see what it does in the next couple weeks.

If this cooler pattern continues, then it might not really matter if we know the exact volume for sure. 2012 and 2011 weren't all that different on volume in August and September. But the 2012 record warmth with the weather pattern made all the difference between the two extent finishes in September. This June is continuing the post 2012 stronger polar vortex pattern vs the 2007-2012 raging dipole regime. We would need a July 2015 rapid reversal to really accelerate the melt. But that kind of reversal isn't showing up in the longer range guidance as of yet. Even Greenland is enjoying a below average melt compared to recent years.

 

meanT_2017.png.a6c1ae747e6eb03cd4240cf19b8eddae.png

greenland_melt_area_plot_tmb.png.3183d07f87ae91683e972202d23f3afc.png

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17 hours ago, Snow_Miser said:

There are no energy accumulation lags. Zero. It is like saying that a pot on a stove will continue to gain energy, even after the burner has been turned off. It makes no physical sense. So the continued upper ocean heat accumulation is totally inconsistent with reduced solar activity. It is just not causing current climate change. 

 

An excellent and concise explanation of the problem with "solar lag" bloggers.

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On 6/25/2017 at 6:30 AM, Joe Vanni said:

Well it seems they rushed it. The research and forecasters I've found to be most accurate at long ranges have stayed with the same story. But that's like me saying how some on the AGW side was claiming ice free Arctic in 2012, 2013, 2014 and so on. It's not going to happen anytime soon; and yes I know how's it's trended since 1979, the beginning of the global warming period. Or how the Atlantic hurricanes were only going to get worse after 2005's record season. They misjudged, but they have misjudged more than just the reason for melting ice and hurricanes.

I think the peak will happen during solar cycle 26/27 but it'll become much more obvious as we approach 25 that something has switched.  I can see why you would point out how we have warmed despite s super weak cycle. But there is actually a legit lag and a point needed to cross to see the real effects on a longer-term. But as I said before, debating this will get us nowhere. People are going to have to start seeing effects at their own house before they realize something is up. 

Again, you are making the same mistake I made 10 years ago. Mainstream consensus science has never predicted a "likely" ice free Arctic before the 2020s at earliest. I believe the modeling continues to suggest a most likely timeframe of late 2020s or 2030s or later. There were a few fringe guys who did not publish peer-reviewed papers that predicted ice free in the years following 2012. Few were fooled by them other than AGW-hype bloggers and AGW-deniers looking for strawmen (like yourself). I spend a significant amount of time the last 5 years arguing against these AGW-alarmist types on this forum. Why? Because I follow legitimate peer-reviewed science not internet bloggers. If you pay attention, there is a core group that has studied and published on the arctic for decades. This group was never on board with an ice-free arctic before 2020. At best, a few might have suggested it was possible with bad enough weather (which actually was possible considering how close we got in 2012). 

Likewise, the mainstream prediction regarding tropical activity has actually always been a low confidence prediction for a net decrease in the # of cyclones and a slight increase in average intensity. It's right there in the IPCC reports. 

So the examples of a few fringe AGW guys without any real credentials or publishing history making fringe predictions that turn out to be wrong is a lot more akin to the fringe bloggers you are following on the internet. They're both wrong.

Likewise I'd like to see a response to Snow Misers clear explanation of why a solar lag cannot exist. When you turn off the stove (the sun) a pot of water will immediately begin to cool (the earth). There is no lag. It doesn't cool down completely immediately. But it begins to cool immediately. In reality, the earth has not started cooling, it has not stopped warming, it hasn't even slowed down its warming. If anything, the data suggests the warming has accelerated.

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3 hours ago, bluewave said:

If this cooler pattern continues, then it might not really matter if we know the exact volume for sure. 2012 and 2011 weren't all that different on volume in August and September. But the 2012 record warmth with the weather pattern made all the difference between the two extent finishes in September. This June is continuing the post 2012 stronger polar vortex pattern vs the 2007-2012 raging dipole regime. We would need a July 2015 rapid reversal to really accelerate the melt. But that kind of reversal isn't showing up in the longer range guidance as of yet. Even Greenland is enjoying a below average melt compared to recent years.

 

 

 

There's actually a pretty good dipole pattern that gets going later this week, but it doesn't look like it will last more than a few days....but I also recall that July 2015 didn't initially look like it was going to last, but it was able to for most of the month. We'll have to see.

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50 minutes ago, ORH_wxman said:

There's actually a pretty good dipole pattern that gets going later this week, but it doesn't look like it will last more than a few days....but I also recall that July 2015 didn't initially look like it was going to last, but it was able to for most of the month. We'll have to see.

We would need a solid dipole pattern to lock in to have a chance of challenging 2012. Otherwise, it's going to be another year that the 2012 record holds.  Seems like the really extreme Arctic conditions for the most part since 2012 have been during the winters instead of the summers from 2007-2012. 

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43 minutes ago, bluewave said:

We would need a solid dipole pattern to lock in to have a chance of challenging 2012. Otherwise, it's going to be another year that the 2012 record holds. 

Agreed with that. The very low volume at the start of the season will make it easier to get into the top 3-5 lowest seasons even if the weather remains kind of mundane, but 2012 is so far ahead of the others that we'll need some pretty big melt weather to catch it.

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1 minute ago, forkyfork said:

it says a lot about the state of the ice that mundane melt weather could still bring a top 5 low finish

IMHO the 2005-2007 period pretty much reset the whole Arctic background state. Arctic amplification really took off at that time when the September avg extents started regularly falling below 6 million sq km on NSIDC. We didn't even need a 2012 record minimum the last few years to set the extreme Arctic warmth records. 

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21 minutes ago, forkyfork said:

it says a lot about the state of the ice that mundane melt weather could still bring a top 5 low finish

The last two winters have definitely been poorer for first year ice with much warmer conditions than the previous 3 winters...though the thermodynamic thickening curve would still have the FYI achieving most of its possible thickness even in those warmer winters...we probably need another 2C or so to really start seriously denting the FYI thickness. I do wish we had better subsurface data on the SSTs up there, because I'm wondering if last year's El Nino played a role in the rapid melt during the 2nd half of the summer by increasing the flow of warm subsurface into the pacific side of the arctic...since last year didn't really have favorable melt weather outside of a very intense dipole for about 2 weeks in August.

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4 hours ago, ORH_wxman said:

The last two winters have definitely been poorer for first year ice with much warmer conditions than the previous 3 winters...though the thermodynamic thickening curve would still have the FYI achieving most of its possible thickness even in those warmer winters...we probably need another 2C or so to really start seriously denting the FYI thickness. I do wish we had better subsurface data on the SSTs up there, because I'm wondering if last year's El Nino played a role in the rapid melt during the 2nd half of the summer by increasing the flow of warm subsurface into the pacific side of the arctic...since last year didn't really have favorable melt weather outside of a very intense dipole for about 2 weeks in August.

There's evidence of significant Atlantic water shoaling over the past 5-10 years. Neven's site had some stuff posted from this paper: https://www.ncbi.nlm.nih.gov/pubmed/28386025

I believe the AW layer was found to have shoaled about 50% of the way to the surface in the last decade on the Eurasian side -- hence the paper's statement of a significant fraction of forcing coming from the ocean now. The issue there is that with additional shoaling, even weaker summer storms will be able to tap that water layer and cause it to interact with the near-surface layer. That may have been part of the issue last summer. I'm pretty sure the Pacific current played a role there too -- but as you say, it'd be nice to confirm that.

Your comment on winter warmth is about right. This winter's FDD anomaly total was around -1750. At around 2000, it begins to seriously undercut spring thickness and at 2500+ maintaining FYI gets pretty untenable even through a cool summer. There isn't much buffer room left there. The good news is that last winter was pretty extreme compared to any other winter, so there's a good chance we'll get a mean-revert this year.

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Ironically, a great deal of ponding has shown up over the past 5 days on EOSDIS. The strong winds, WAA and chinook-type event off the Kolyma range on the forward flank of the storm did a great job of breaking the inversion and eradicating snow cover, jumpstarting melt-ponds. The O-buoy 14 pictures show that as well, going from solid snow cover to solid melt ponding in less than 2 days. Melt should slow considerably for the next 3-4 days. However, the upcoming pattern has downsloping flow off the Brooks range for an extended period, which will serve to push the Chukchi/Beaufort front back pretty quickly.

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