Guest Post by Willis Eschenbach
Inspired by this thread over at Bishop Hill’s excellent blog, I thought I’d write about sea ice. Among the many catastrophic things claimed to be the result of “global warming”, declining sea ice is one of the most popular. We see scary graphics of this all the time, things that look like this:
FIgure 1. Terrifying computer projections showing that we may not have any Arctic sea ice before the end of this century. Clearly, the implication is that we should be very concerned … SOURCE
Now, what’s wrong with this picture?
The problem with the picture is that the earth has two poles. And for reasons which are not well understood, when one pole warms, the other pole cools.
Looking at just the Arctic sea ice is like looking at someone who is pouring water from one glass to another and back again. If we want to see how much water there is, it is useless to observe just one of the person’s hands. We need to look at both hands to see what is happening with the water.
Similarly, to see what is happening in the frozen parts of the ocean, we need to look at global sea ice. There are several records of the area of sea ice. One is the Reynolds Optimally Interpolated dataset (Reynolds OI V2). A second is the National Snow and Ice Data Center (NSIDC) record. Finally, we have the Hadcrut Ice and Sea Surface Temperature dataset (HadISST1). All of them are available from that most marvellous resource, the KNMI data portal .
It turns out that the NSIDC and the HadISST1 records are nearly identical. The correlation between the two in the Arctic is 0.995 (1.0 is perfect agreement), and in the Antarctic it is 0.999. So in Fig. 2, I have not shown the NSIDC dataset, but you can imagine that there is a third record almost identical to the HadISST1 dataset. Here is what has happened to the global sea ice area from 1982 to the present:
FIgure 2. Global Sea Ice Area 1982-present. Data from satellite observations.
As you can see, while it is certainly true that the Arctic has been losing ice, the Antarctic has been gaining ice. And the total global sea ice has barely changed at all over the period of the record. It goes up a little, it goes down a little, it goes nowhere …
Why should the Antarctic warm when the Arctic cools? The short answer is that we don’t know, although it happens at both short and long time scales. A recent article in Science Magazine Online (subscription required) says:
Eddies and the Seesaw
A series of warm episodes, each lasting several thousand years, occurred in Antarctica between 90,000 and 30,000 years ago. These events correlated with rapid climate oscillations in the Arctic, with Antarctica warming while the Arctic was cooling or already cold. This bipolar seesaw is thought to have been driven by changes in the strength of the deep overturning circulation in the North Atlantic Ocean, but some have questioned how completely that process can account for the fine details of Antarctic warming events.
Keeling and Visbeck offer an explanation that builds upon earlier suggestions that include the effects of shallow-water processes as well as deep ones. They suggest that changes in the surface salinity gradient across the Antarctic Circumpolar Current were caused by the melting of icebergs discharged from the Arctic, which allowed increased heat transport to Antarctica by ocean eddies. This mechanism produces Antarctic warming of the magnitude observed in ice core records.
However, not everyone agrees that this is the full explanation. Henrik Svensmark adds another factor to what may be happening:
The cosmic-ray and cloud-forcing hypothesis therefore predicts that temperature changes in Antarctica should be opposite in sign to changes in temperature in the rest of the world. This is exactly what is observed, in a well-known phenomenon that some geophysicists have called the polar see-saw, but for which “the Antarctic climate anomaly” seems a better name (Svensmark 2007).
To account for evidence spanning many thousands of years from drilling sites in Antarctica and Greenland, which show many episodes of climate change going in opposite directions, ad hoc hypotheses on offer involve major reorganization of ocean currents. While they might be possible explanations for low-resolution climate records, with error-bars of centuries, they cannot begin to explain the rapid operation of the Antarctic climate anomaly from decade to decade as seen in the 20th century (figure 6). Cloud forcing is by far the most economical explanation of the anomaly on all timescales.
Regardless of why the polar see-saw is happening, it is a real phenomenon. Ignoring it by looking just at the Arctic leads to unwarranted conclusions about what is happening to sea ice on our most amazing planet. We have to look at both hands, we have to include the other side of the ice, to see the full situation. The real answer to what is happening to global sea ice is …
Nothing.
Re: Anu (23:19:11)
You’re bringing up Barber’s “rotten ice” claim that was demolished here last year and has become a running gag?
Why? Did you catch it?
Willis – you said:
QUOTE
And all of that costs money. That’s why I see the fight against carbon as being totally and tragically misguided, not just because it is futile, but mainly because for the foreseeable future at least, carbon = development.
UNQUOTE
I agree completely.
I am horrified by the lack of understanding of economics by so many people (scientists, politicans and lay public).
So many do not realise that their weekly income depends on the economy, regardless of if they run their ouwn business, work for a company or have a position with the government, teacher, doctor, nurse etc.
Our economy is based on carbon.
Pat,
When willis is saying Carbon = Development, I am pretty certain he is saying that burning fossil fuels is, for the present, our best way to develop. In that I assume economic and technological development.
Anu (23:19:11), as always, good to hear from you, you usually bring science to the discussion.
Interesting stuff, but only on a press release level. For starters, the IceSat satellite is supposed to be the source of their data. But the IceSat satellite doesn’t cover any further north than the other satellites, about 82.5°N. And their lovely graphs show all the way to the pole … how do they do that? They don’t say …
Next, none of that is surprising. In a time of decreasing ice area, and during the first year of the recovery from the low ice area, would you expect more or less multi-year ice?
Very good, concise and to the point. Not to mention hilarious.
Unless they’re talking about something different than what are usually called “polar cyclones”, I don’t understand that comment. Polar cyclones are semi-permanent features of the Arctic, which are stronger in winter and weaker in summer. How could there be “more cyclones”? I think the news article you took this from didn’t understand what they were talking about.
Yet despite all of that, the ice area has increased every year since the 2007 low. Go figure …
So are you saying we can’t trust the satellite results? If so, why are you showing them? Not clear what the point is here.
Yeah, it’s only lasted for hundreds of thousands of years …
Anu, was there a decrease in the ice area and thickness in the Arctic? Yes. Has the sea ice area increased since 2007? Yes. Was there less multi-year ice 2004-2008? Yes, and it would be surprising if that were not the case.
Has the thickness recovered by 2010? We don’t know, because unfortunately, the IceSat laser instrument (the only instrument on the satellite) died in 2009 …
Now, remember that this was all big news in 2007. At that time, all the ice savants were predicting that because there was less multi-year ice in the Arctic, that in 2008 the ice melt would be much larger and the ice area would be smaller … didn’t work that way, though.
The same prediction was made for 2009, and for 2010, for the same reasons – the thinner ice would melt easier and faster, so we’d see less ice than the previous year.
But none of that happened … instead, the Arctic ice area has increased. At present it is within one standard deviation of the 1979-2000 average, and is continuing to rise well past the date of the usual peak. Seems like the savants must have slipped a decimal point somewhere.
Me, I suspect this is because of the shift in the Pacific Decadal Oscillation (PDO). In 1976-77, just before the start of the satellite record, the PDO shifted (as it does every thirty years or so) from the cool phase to the warm phase. The effects of this were felt all over the Arctic. The effects on Alaska can be seen here in Update 5. The effects on the Arctic as a whole can be seen in Update 10 on the same page.
As can be seen in that graph of Alaskan temperatures, however, the PDO recently shifted back to the cool phase. This will once again affect all of the Arctic.
However, all of that is just the Arctic. My point remains. Global sea ice is unchanged.
This’ll make you puke!
Pa. global warming researcher calls self ‘skeptic’
“I’m a skeptic. When I see a scientific claim being made, I want to see it subject to scrutiny and validation.”
Mann said there is firm grounding for some climate science assertions,…
[snip – lets leave Nazi’s out of the discussion – Anthony]
http://www.ldnews.com/news/ci_14774756
With regard to sea ice volume,my recollection is that when it became obvious that the sea ice in the Arctic was back to ‘normal’, and it was observable, the alarmists had to come uo with something that was not so observable, the thickness of the ice. My suspicion with the NSID graph posted above is that the assummed decline in the sea ice extent is easy to hide, but the peak is not as there are fixed points where the waves are not lapping on th shores?
I thought there were six poles,true north,magnetic north and grid north?
At Max. If you don’t want to upset the barbarian celtic hordes in the uk, better to say you prefer imperial units instead of English units. Of course you may then upset the former Colonies, your call ;-/
BBC: Gulf Stream ‘is not slowing down’ So that bang goes the favourite retort of warmers when I mention the worst winter in 50 years (in Scotland)
The Gulf Stream does not appear to be slowing down, say US scientists who have used satellites to monitor tell-tale changes in the height of the sea.
http://news.bbc.co.uk/1/hi/sci/tech/8589512.stm
comment to mr jorgekafkazar
Certainly some dutchmen are putting a lot of confidence in the future climate by imagining more land taken from the sea below the sea-level . A whole industries existence is built upon the fact that the sea-level does not substantially rise or fall . Of course there exists as well a strong robust AGW-movement led by farmer Veerman , also a marxist-type of scientist typical for a lot of goverment paid university-staff , living a life far away from reality and not open for any criticism regarding their view-points . Luckily there are still a lot of sound thinking dutchmen with an enterprising attitude
Alexander Feht (22:14:50) :
Nobody made such an assertion (at least in this thread).
By bringing in the center of mass idea and using the word ‘nadir’ there you have the assertion [granted that it is clumsy and imprecise].
The question is: how it affects the characteristics of solar activity and, therefore, the climate on Earth?
1st, since the Sun is in free fall it does not not feel any forces and there is then no effect on solar activity. 2nd, the effect of solar activity on climate is so small that it has not yet been convincingly demonstrated.
DeNihilist (22:35:44) :
Somehow these rays are supposed to be counter to Einstien’s theory of relativity.
Discover Magazine sometimes makes claims that are less than accurate. I’m not aware of any phenomenon that runs counter to the theories of relativity.
It is difficult to see why ocean currents should be to blame for this phenomena, given that ocean currents effectively start at the equator and then split into two separate streams according to north and south (unless of course you believe the thermohaline model for ocean circulation is fundamentally flawed and that ocean currents are primarily driven by tidal forces, as was the predominant theory up until Team AGW decided it was expedient to claim that the Gulf Stream was about to stop).
A solar source for the apparent synchronicity between the poles is much more likely, so a theory that predicts such a relationship as a result of a solar source is inherently more plausible
Al Gored (18:59:28) : You refer to ‘watermelons’.
I think this refers to vegetables which are green on the outside and red on the inside.
Bad metaphor. The vegetable is useful.
How is it that almost all of the black line is below 0? Surely half of it should be above.
Ah, it’s only a 10 year mean, but they’ve got 27 years of data.
Climatologists claim to have found Biblical plagues
Researchers studying global warming claim they have found proof of the biblical plagues which were first reported in the Bible and in the flick “The Ten Commandments”.
Climatologists discovered a dramatic shift in the climate in the area occurred towards the end of Rameses the Second’s reign.
After looking at stalagmites in Egyptian caves they have been able to rebuild a record of the weather patterns using traces of radioactive elements contained within the rock.
http://www.techeye.net/science/climatologists-claim-to-have-found-biblical-plagues
Comment:Isn’t it great to be back in the good old days, when any historian seeking a bit of evidence to fit their tin-pot theory of history would search out a useful bit of climate change and then adjust the events to fit the evidence, rather than pretty much vica versa as now!
The significance of snow and ice is their albedo effect and the related positive feedback mechanism. When it’s cold there is more snow and ice and more energy is reflected and its gets colder which leads to …. and of course vice versa. One metric which is relevant but not often reported is total sea-ice and snow. This shows a very minor declining trend (3% over 30 years).
http://www.climatedata.info/Impacts/Impacts/snow.html
kadaka (23:08:35) :
And if some group computer-model projected that the Sun would fry the Earth through increased luminosity in 30 years, would you take thier ‘prudent action’ advice and propel the Earth out further in orbit?
There’s an app for that. It’s called Lucasfilm, and it’s intended to be for your entertainment, not the subject of your nightmares.
In a previous post someone pointed out that the 15% sea ice graphs are pretty worthless, which is true.
However, they also said at 30% i6t was currently declining, a trend which has dramatically reversed now it would appear:
http://ocean.dmi.dk/arctic/icecover.uk.php
davidmhoffer (18:48:32) : You asked, “Odd… GISS shows both to be warming since 2000 while your graph shows south to be cooling.”
The two SST datasets, OI.v2 SST (used by GISS) and ERSST.v3b, both show the Southern Ocean to be cooling since Nov 1981, but the OI.v2 data shows a rise and decline since 2000 while the ERSST.v3b data does not:
http://i39.tinypic.com/jglki1.png
That leaves the LST data. The NCDC, for that dataset, uses a different method of infilling LST than GISS (which uses the 1200km smoothing). Refer to:
http://www.ncdc.noaa.gov/oa/climate/research/sst/papers/SEA.temps08.pdf
You asked, “They measure 64 – 90 instead of 60 to 90, but does that account for the difference?”
Nope. The datasets with less coverage have greater year-to-year variations, but the datasets mimic one another. Here’s a graph of the GISTEMP Antarctic LST+SST anomalies, 90S-60S versus 90S-64S:
http://i41.tinypic.com/ofcy9z.png
Here’s one for the Arctic (60N-90N versus 64N-90N):
http://i43.tinypic.com/2h3zfpg.png
And if you’re interested, here’s a comparison of the GISTEMP Arctic versus Antarctic LST+SST anomalies:
http://i40.tinypic.com/n4fhpw.png
It also contradicts the statements that one pole warms while the other cools.
The very latest from the BBC on the Gulf Stream
http://news.bbc.co.uk/1/hi/sci/tech/8589512.stm
Anu (23:19:11) :
Ahh, we are back to the “its rotten ice” nonsense again.
Basil (19:52:28) : You asked, “How did you handle all the missing data in the Southern hemisphere dataset?”
I left them as blank cells in EXCEL. And the spans with no data were so long that I couldn’t use 13-month smoothing without having gaps, hence the 37-month filter.
“The problem with the picture is that the earth has two poles. And for reasons which are not well understood, when one pole warms, the other pole cools.”
Now add the established fact that the poles are the focus of large Birkeland Currents (which when current density increases cause the auroras to appear), and as part of an electric circuit, energy in balances energy out.
Most of us think of electricity as the stuff that flows through copper wires, and yes, its the electrons moving, but when we get to the plasma state, both charged particles move, positive ones in the opposite direction to the negative ones.
So in one sense, electrically, we get energy coming into the earth system, but as electric currents also move out the of the earth-system, then energy is bening taken out of the earth system.
And with these arcane comments I show that our understanding of the earth system is somewhat incomplete if we ignore the plasma factor.
The Team ignore it and hence limited by their post modernist application of Victorian gas-light era physics, search for the nearest target to blame for their scientific ignorance – humans.
Where are Phil and Da Witty Pain LOL?
At this rate I would surmise that NH ice may be on route to COMPLETE NORMALITY or even slightly ABOVE anomaly for the rest of year.
http://ocean.dmi.dk/arctic/icecover.uk.php
If so it would be the physical end of AGW this year as this is a VERY IMPORTANT pillar for the Warmistas. How will they argue this one off?
Oh I know…. Antarctica will start to melt…LOL
The figure 6 in the Svensmark quote is here.
http://www.phys.uu.nl/~nvdelden/Svensmark.pdf