Arctic Sea Ice Volume at record low.

[Furcifer]

Indeed we do differ, only fools, idiots and psychopaths face danger without fear. This isn't to say that fear should dominate or control our thoughts or actions, but it must always temper those considerations.

Dismissing or ignoring proper and appropriate emotions such as the fear of dire consequences as the result of dangerous situations, does not eliminate the fear or the danger, it merely blinds you to information and considerations that can and should be important to your decision making process. Understanding and acknowledging the fear of dangerous consequences is not harmful, ignoring the danger or pretending the fear doesn't exist can be.

Like I said are there any particular dangers, or the fears of dire consequences associated with any particular danger, that you would like to talk about in more detail?

Around here the only people who fear melting ice are fishermen

There is absolutely no danger in sea ice melting and the claim that this is "scary" is unwarranted. For the most part it represents a better quality of life for many people.

 

[BenBurch]

There is a really good reason why Antarctic ice is stupid to even bring into this; All climate simulations show that is the LAST place on the planet that will respond to warming. And in fact they show there may be some ice accumulation there because increased warmth brings more humidity. Its an utterly different place than the arctic.

EDIT: I encourage you to start an Antarctic Ice thread, but stay on topic here, please.

 

[BenBurch]

Oh, and those anomaly graphs you posted? Those are EXTENT anomalies, not volume anomalies. And this thread is about ice VOLUME.

 

[Grizzly Bear]

I only quoted a portion of the section from the Skeptical Science page directly addressing why Antarctic sea ice was increasing in a warming Antarctic ocean. The entire page addresses the differences and similarities of arctic and antarctic ice. It only takes a few minutes to read and it is complete with linked supporting references and publications.

http://www.skepticalscience.com/antarctica-gaining-ice.htm

No I read the article. It discusses several factors to explain the ice coverage but it does not address the very clear correlation between these levels from year to year which the OP, and its source egregiously omits.

 

[CapelDodger]

No I read the article. It discusses several factors to explain the ice coverage but it does not address the very clear correlation between these levels from year to year which the OP, and its source egregiously omits.

There isn't a clear correlation between Antarctic and Arctic sea-ice. That's easily seen by eye. Unless you're referring to 2007-8, which could be entirely coincidental.

Geologically, Antarctica and the Arctic Ocean are complete opposites. Antarctica is a continent (much of it very high, with ice on top) while the Arctic Ocean is, you know, an ocean. All of it at sea-level with at most a thin covering of ice. A significant amount of Antarctic sea-ice comes off the land onto the sea, whereas very little does in the Arctic. Antarctica is relatively isolated from the rest of the world's climate (because of the Circumpolar Current and airflow) while the Arctic is closely connected to it, via ocean currents mostly.

The local effects of global warming can be expected to be very different in two such different situations. So bringing the Antarctic into the subject of the Arctic serves no purpose except to divert.

 

[CapelDodger]

There is a really good reason why Antarctic ice is stupid to even bring into this; All climate simulations show that is the LAST place on the planet that will respond to warming.

Basic reasoning leads to that conclusion, just as it leads to the Arctic being particularly sensitive to global warming and in a very visible way. The canary in the mine, so to speak.

And so it has proved.

 

[CapelDodger]

Source? I wasn't aware of a point system here at the JREF.

Nor me. I doubt there is one.

If there were I would guess playing semantics is a negative. Whether baseline or trend-line is irrelevant to the discussion.

No it isn't. And you are simply mis-using the term "baseline".

As an anomaly it remains a weather event as well.

It's an anomaly in estimated sea-ice volume, and sea-ice volume is not weather. It's sea-ice.

Again I fail to see the reason for you pointing this out?

Perhaps now you do.

Why not address the question at hand? What exactly is "scary" about an ice thaw?

That's only the question you'd like to keep in hand. Its clear from the original context that "scary" doesn't refer specifically to an ice-free Arctic. It refers to what an ice-free Arctic, much earlier than predicted even ten years ago, implies for climate change in general.

Are you proclaiming this a "runaway" event? Does this represent a dangerous condition?

Are you disappointed that I didn't say this, so you've decided to pretend that perhaps I did?

Arctic sea-ice loss can't run away far. It'll soon run out even at the current rate.

 

[Furcifer]

Nor me. I doubt there is one.



No it isn't. And you are simply mis-using the term "baseline".



It's an anomaly in estimated sea-ice volume, and sea-ice volume is not weather. It's sea-ice.



Perhaps now you do.



That's only the question you'd like to keep in hand. Its clear from the original context that "scary" doesn't refer specifically to an ice-free Arctic. It refers to what an ice-free Arctic, much earlier than predicted even ten years ago, implies for climate change in general.



Are you disappointed that I didn't say this, so you've decided to pretend that perhaps I did?

Arctic sea-ice loss can't run away far. It'll soon run out even at the current rate.

So if I presented evidence that much more knowledgeable people than yourself referred this as "baseline" you'd recant? Can you cite any relevant articles that show the term "baseline" is a total misnomer and "trendline" is significant?

I doubt it. My money is on you trying to change the subject in the same way you've already demonstrated.

Scary sea ice, lol. How very alarming.

 

[Trakar]

No I read the article. It discusses several factors to explain the ice coverage but it does not address the very clear correlation between these levels from year to year which the OP, and its source egregiously omits.

Which specific correlation are you talking about? How significant is the correlation and what testable mechanism are you proposing as causing this proposed correlation? I thought you were simply referencing the differences between arctic and antarctic sea ice (big difference is that there is no antarctic polar sea ice, because there is no polar sea anywhere within 1300km of the pole). If you are proposing a connection beyond the fact that both are warming and generally loosing net ice mass, please feel free, but let's try to stick to facts, verifiable numbers and science in both the presentation of fact and the analysis of that hypothesis. Popping up graphs pulled from a political discussion blog, saying that they present what to you looks like a correlation, is neither factual nor scientific in presentation or anaylsis.

The OP may well consider this a derail as it is not addressing this thread's topic, but I would be willing to look at and comment upon your proposal in this or a new thread specifically started to address the topic, if you wish to put forth the effort to produce a functional hypothesis and appropriately support it.

 

[BenBurch]

For those who are confused; Extent is measured in square kilometers, volume is measured in cubic kilometers.

A given square kilometer of ocean is judged to be ice-covered for purposes of extent if more than 15% of its area is ice, not water.

A volumetric measurement takes into account the sum of all of the ice-covered areas and the thickness of that ice.

Now, that 16-percent-covered square kilometer of ocean probably does not add much to the volume measurement, and because volume is proportional to energy required to melt, will probably melt to open water sooner rather than later.

Even 100% covered polar pack ice a meter thick does not contribute much to volume - you'd need 1000 square miles like that to be one cubic kilometer of ice.

Most of the volume, therefore, is not in the single-year-old meter thick pack ice, but in the MUCH thicker ancient ice that has been accumulating snow and ice in the arctic for years and years.

And a remarkable thing started happening a couple of decades back; The ancient multi-year ice started disappearing. What was happening with it? Some was melting, some was breaking free from the pack ice and following the Greenland-Iceland current down into the Atlantic, where it melted in the warm waters.

Now there is very, very, very little of that ancient ice left.

 

[Trakar]

...
Now there is very, very, very little of that ancient ice left.

Actually,...in another couple of months, that ancient arctic ice should make up most of what little there is, but I know what you mean. The implications are disconcerting.

 

[lomiller]

How does it explain the correlation between arctic and antarctic sea ice levels as shown in my last post though? Would you mind clarifying?

There is no correlation. the Antarctic is doing different things for different reasons and provide no insight at all as to what's happening in the Arctic. Furthermore you are not even looking at comparable numbers. Ben's OP was about ice volume not ice extend, which is what you linked to.

At this point we don't know if anything is happening with Antarctic Sea ice extent let alone volume. What is interesting though is that Antarctic sea ice extent is holding steady or possibly even increasing very slightly (this bounces in and out of statistical significance) despite much warmer air and water temperatures. There is at least some speculation that reduced surface salinity from glacier melt-water.

Anyway given the different causes, observed phenomenon, different dynamics and even differences in the data trying to lump the Antartic in with the Arctic seems like an attempt to muddy the waters rater then add clarity or insight.

 

[Dancing David]

How does it explain the correlation between arctic and antarctic sea ice levels as shown in my last post though? Would you mind clarifying?

The antartic is on a land mass the artic is open sea. (Sometimes covered with ice.)

 

[Mikemcc]

For those who are confused; Extent is measured in square kilometers, volume is measured in cubic kilometers.

A given square kilometer of ocean is judged to be ice-covered for purposes of extent if more than 15% of its area is ice, not water.

A volumetric measurement takes into account the sum of all of the ice-covered areas and the thickness of that ice.

Now, that 16-percent-covered square kilometer of ocean probably does not add much to the volume measurement, and because volume is proportional to energy required to melt, will probably melt to open water sooner rather than later.

Even 100% covered polar pack ice a meter thick does not contribute much to volume - you'd need 1000 square miles like that to be one cubic kilometer of ice.

Most of the volume, therefore, is not in the single-year-old meter thick pack ice, but in the MUCH thicker ancient ice that has been accumulating snow and ice in the arctic for years and years.

And a remarkable thing started happening a couple of decades back; The ancient multi-year ice started disappearing. What was happening with it? Some was melting, some was breaking free from the pack ice and following the Greenland-Iceland current down into the Atlantic, where it melted in the warm waters.

Now there is very, very, very little of that ancient ice left.

[pedant] I'm assuming you meant kilometres there! [/pedant]

 

[BenBurch]

Yes. English measurement habits die hard. Sometimes they even crash into Mars.

 

[BenBurch]

Wow, I am biting my tongue. Hard.

For those who want to focus on extent measurements, http://nsidc.org/data/seaice_index/images/daily_images/N_stddev_timeseries.png is interesting just now for the damn-near linear decline that is below the 2007 track.

 

[Almo]

That's kind of scary, actually.

Why?

accelerated rate of change

That. If there is truly an acceleration on the rate of change, then you have a problem.

Say you have a car. It's going 10 mph, and is accelerating at 1 mph / day. it's going to take you a month to get up to 40.

But what if someone is pushing the gas pedal slowly and steadily? Suppose now its velocity change is accelerating at 1mph / day?

Day 1: 10 mph
Day 2: 11 mph
Day 3: 13 mph
Day 4: 16 mph
Day 5: 20 mph
Day 6: 25 mph
Day 7: 31 mph
Day 8: 38 mph

8 days instead of 30. The problem is this gets worse and worse the longer the pedal is pressed harder.

You're really in trouble if for some reason the rate of pressing the pedal increases with speed.

3 standard deviations below the trendline is a lot in statistical terms.

So I find that data scary, if it is valid data, because of the math above.

 

[Hindmost]

http://nsidc.org/seaice/characteristics/difference.html

Here is a reasonable source.

glenn

 

[uke2se]

Perhaps if you weren't trolling you'd know this. Try reading the thread.

Try answering a question instead of dodging and weaving?

 

[uke2se]

There's a direct correlation starting at 1979.

Prove it.

Because the University of Illinois graphs certainly don't.