Guest Post by Willis Eschenbach
I got to thinking about snow the other day. It was occasioned by my look at the correlation (both positive and negative) of temperature and albedo. Albedo is a measure of how much sunlight is reflected from the clouds and the surface. The greater the albedo, the more sunlight is reflected. Here’s the graph that set me pondering:
Figure 1. Correlation between surface temperature and albedo. Negative correlation (blue and green) means the albedo goes down (less reflected sunlight) as the surface warms. Positive correlation (red and orange) means the albedo goes up (more reflection) as the surface warms. Gray line shows zero value.
In the red and orange areas, which are mainly in the tropics, the albedo goes up as temperatures rise. This is generally because clouds form as temperatures rise, reflecting more sunlight and cooling the earth. In the blue and green areas, on the other hand, the albedo goes down as temperatures rise. Over the extratropical land, much of this change is from snow and ice. As the land warms, snow melts and the albedo goes down. And as the land cools, snow falls and the albedo goes up. This is a positive feedback, with warming leading to increased solar energy, and cooling leading to less solar energy.
One thing that is highlighted by this map is that the positive feedback from the changes in sea ice are much smaller than the feedback from the changes in snow and ice on land, for several reasons.
The first one is the small area of the sea ice variations. Note that the feedback is only in the areas that are seasonally uncovered and covered by sea ice—permanently ice-covered areas don’t have much albedo change. Net annual variation in Arctic sea ice is about ± 5 million square kilometres. This is only about 1% of the area of the globe.
Another reason the changes on land are larger is that when snow melts, it exposes soil and plants, both of which have low albedos. But when sea ice melts, it reveals ocean … and the albedo of the ocean at low sun angles is already pretty high. As a result, the melting of the ice doesn’t change the albedo as much as the melting of the snow.
Another reason the land varies more is that snow extends much closer to the equator than sea ice. As a result, the sun rises much higher over snow than sea ice, and thus the snow intercepts more sunlight than the same area of ice up near the poles.
Another reason is that as you can see from Figure 1, the negative correlation of the albedo and temperature is greater over northern lands than northern oceans.
All of this has made the snow-covered areas of the northern hemisphere the main suspects in the onset of the ice ages. The generally accepted theory is that the so-called “Milankovitch” variations in the earth’s orbit change the amount of sunshine hitting the northern hemisphere. When the northern hemisphere summer sunshine gets weak enough, the snow on the northern land doesn’t melt back as far. This residual snow reflects more sunlight, which leads to cooler temperatures, which leads to more snow, which leads to more reflected energy … I’m sure you can see the end of this story, glaciers a mile thick covering Chicago.
Now, people seem to have a strange need to believe in some kind of existential threat hanging over our heads. There appears to be a desire to worry about something, as long as it is dire and a couple of decades away. In the past we’ve filled this need by worrying about the “population bomb”, or the “ecological footprint”, or the dreaded arrival of “peak oil”. Nowadays, it seems like “global warming” is taking over the role of the scourge du jour.
Me, I prefer to only concern myself with real possibilities of real harm. We’ve seen a couple of degrees warming since the Little Ice Age, and overall the effects have been beneficial to humans, plants and animals. I have no concern about the fabled Thermageddon of a couple degrees more warming—the effects are not grave, will likely be beneficial, and I have strong doubts that it will happen this century.
Another ice age, on the other hand, seems to be both inevitable and very destructive. And to raise the stakes, near as scientists can tell the next ice age either due or overdue … this is already the longest of the “interglacials”, the historical periods in between the ice ages.
So I would suggest that we keep a fairly close watch on the snow cover of the northern hemisphere. Because when the apparently inevitable ice age comes ’round again, it seems to me that the first sign will be an increase in the snow cover in North America and Eurasia.
Fortunately, the good folks at Rutgers University have a dataset showing the weekly area of the extent of the snow in the northern hemisphere that goes back forty years or so. Here’s that data:
Figure 2. Rutgers University snow extent data. Note the missing data prior to 1972. Data Source: Rutgers Snow Extent Data
So … how is the extent of the snow trending over time? Well, if we look at the complete data, which extends from 1972 to present, here’s how that breaks down:
Figure 3. Decomposition of Rutgers snow extent data. Top row is observations. Second row shows the trend in the 52-week mean. Third row is the regular seasonal variations. Bottom row is the residual variation once the seasonal and overall trends are removed. Note the different scales on all four rows.
The second row in Figure 3, entitled “trend”, shows the changes in the mean value over time. The snow area generally dropped during the first half of the record. Subsequently, it first rose and then remained level in the second half. So the good news is that we don’t appear to be started into an ice age. The other good news is that we also don’t seem to be headed for a time when our children won’t recognize snow … overall, like most climate records, not a whole lot going on. However, that is unlikely to last forever.
Finally, some speculation. I have long held that the main two ways that we affect local climate are through land use, and also via airborne soot (or “black carbon”) and “brown carbon”. Brown carbon is the airborne carbon from inefficient combustion of wood, coal and other fuels. In addition to coming from forest fires, brown carbon mainly comes from billions of cheap stoves and open cooking and heating fires in the developing world. Because of the prevailing winds, a goodly amount of the soot and brown carbon produced in the northern hemisphere falls on the northern snow and ice. And because the carbon compounds are dark in color, they are warmed by the sun. This leads to a more rapid melting of the snow. It has been suggested that this is the reason for the retreat of the European glaciers since the 1800s.
Now, humans have been dumping large quantities of soot into the atmosphere for quite some time now, ever since we managed to tame fire. And presumably, for all that time that soot has helped to melt the northern hemisphere snows and glaciers, so they didn’t start lingering further and further into summer. So … would it not be truly ironic if pollution, in the form of soot and brown carbon, were all that has been holding off another ice age? And wouldn’t it be a cosmic joke if our efforts to clean up soot and brown carbon pollution were the straw that broke the back of the Holocene, and ushered in the new ice age?
Do I think that’s the case, that soot is all that is keeping the next ice age at bay? Y’know … I truly don’t have a clue whether that’s true or not. That’s one beauty of climate science, that there are so many mysteries.
I’m just saying, I’m keeping an eye on the snow extent …
w.
DATA AND CODE:
I’ve posted up a .csv file containing the Rutgers data here, and the R code to read it is here.
The Holocene is not the longest interglacial. The Eemian lasted longer, & considering just the last 500,000 years, MIS 11 was the longest. It was also probably the warmest. Going all the way back to the onset of the Pleistocene, there may have been longer interglacials, but I don’t know.
Good read Willis, I’m keeping my eyes on the snow cover too as I might want to get the car out of the garage.
I’ve shovelled all the low albedo I want to. So, if we don’t get much in Richmond and lot’s where I’m not, that’s just fine.
Thanks. Great read. Scrap all the climate models and concentrate on land use, welcoming the increased CO2 since it keeps the temperate region from going into an ice age, but does no damage to the tropics, since there is already a sufficient negative feedback from increased albedo.
Correction, I shovelled lot’s of low albedo on the farm and the high albedo when I lived in the frozen north. My kids who live in Michigan and Alaska can shovel the high albedo for me. I’ll stick to looking at the low variety.
The areas of strongest NEGATIVE correlation would appear to be areas susceptible to formation and disappearance of glaciers – the northern Great Plains and Rocky Mountains of the US and areas of Tibet, Mongolia and Khazakstan. These would also seem to be areas where the ambient temperature cycles most frequently above and below 0° C.
milodonharlani says:
October 18, 2013 at 11:16 am
Thanks, Milodon. Whether the Holocene is the longest interglacial depends on how you define “length” regarding an interglacial. It is either the longest or second longest depending on that definition. And there is also debate on the question of “warmest”.
My point remains. By all astronomical Milankovitch calculations, we should be falling back into an ice age somewhere around now. To date there’s no sign of it, which is good … but there’s always tomorrow.
All the best,
w.
“So … would it not be truly ironic if pollution, in the form of soot and brown carbon, were all that has been holding off another ice age? And wouldn’t it be a cosmic joke if our efforts to clean up soot and brown carbon pollution were the straw that broke the back of the Holocene, and ushered in the new ice age?”
—————————————-
As a geologist, I have often contemplated the same thing.
3 inches of fresh snow on the west side of Denver this morning & 2nd snow of the week. The snow season here on the Front Range is definitely getting off to a faster start than recent years.
I think that changes in global albedo caused by solar induced cloudiness variations override the balance between the reflective capabilities of the equatorial and poleward regions which Willis has noted.
If solar activity were to remain stable then the former would pretty much balance the latter with variations in ice and snow towards the poles matching opposite sign variations in equatorial cloud activity.
More snow and ice towards the poles would cool the system by reflecting more solar energy but the reduced climate activity would result in less active equatorial clouds and more solar energy into the oceans to compensate.
Less snow and ice towards the poles would warm the system by reflecting less solar energy but the increased climate activity would result in more active equatorial clouds and less solar energy into the oceans to compensate.
That would be in accordance with the various thermostat theories that have been around for some time.
However, I suggest that when solar variations occur that balance is upset and the proportion of ToA insolation getting into the oceans can change without a sufficient compensating change elsewhere and that will drive changes in the energy content of the entire climate system (which includes the oceans).
I have previously explained how solar variations are amplified because the sun can alter global cloudiness by changing the gradient of tropopause height between equator and poles via UV effects on ozone amounts and ozone distribution in the stratosphere.
My New Climate Model describes the consequent cascade of events that results in the observed climate changes.
The effects of soot and aerosols et al in the troposphere would only slightly influence the balance between snow, ice and equatorial clouds. The big game changer is solar induced variations in global cloudiness, albedo and the proportion of ToA insolation that enters the oceans
don’t forget, when Antarctic ice is out to 60 south…..that’s the equivalent of all of Alaska and most of Canada
In case I’m still the first person to mention this, the second paragraph has an error. I think sentence six should be “And as the land cools, snow falls and the albedo goes up.”
[Thanks, fixed. -w.]
Willis Eschenbach says:
October 18, 2013 at 11:33 am
No matter how you define it, MIS 11 (the Vigo interglacial) & the Eemian were longer than the Holocene to date. A lot longer in the case of the Vigo (~31,000 years).
http://onlinebiblio.lneg.pt/multimedia/associa/base%20mono/34834.pdf
Peak warmth of the Vigo is somewhat controversial.
Opinions differ as to the probable length of the Holocene. Some think it will be a super-interglacial, possibly lasting up to two 26,000-year equinoctial precessions, instead of the usual fraction of one (the Vigo excepted). Other students of the subject agree with you that it might not even equal the ~16,000-year Eemian, which is also my not very well-informed opinion.
My first reply here in a while, but funny you should mention the fact that you were thinking about snow.
It wasn’t long after my first read of the article that I started seeing snowflakes coming down in our area. (I’m not kidding, Wichita Kansas in mid October, and it’s snowing). To my knowledge this is even earlier than the 1992 snow that fell around Halloween (despite this one not accumulating yet). It seems to me like you’re right on the money of there being no danger of kids not knowing what snow is (or maybe the EPA’s newly minted CO2 regulations worked a lot faster than we thought and the planet’s now saved, joking by the way).
On top of that, the last spotting of flakes earlier this year was May 1st, which was part of an unusually drawn out series of cold snaps. If our early snowflake spotting becomes a good hint of what to expect during the Winter, than it looks like those forecasting severe cooling and rising snow-cover might be onto something. If the soot up north is indeed delaying the more severe cooling, than perhaps one should consider emitting more of it so we can maintain our growing seasons (and with the extra CO2 become ever more productive).
Willis, it is nice to know I am in the same boat with you in thinking that land use and soot are the main two affects on local climate. This is where we take most of our measurements of weather to “create” local/regional/world climate values. We measure in areas most affected by land use changes and soot production.
Seems like a new and important look at the data. Willis’ conclusions fit with the ice-core records showing the fall-off in temperature since the Holocene optimum is more gradual than after previous optima. The analysis also suggests that humans are in a position to make the next ice-age rather mild.
Willis
Before dismissing “peak oil”, look at the data graphed by petroleum geologist Jeffrey Brown in The Export Capacity Index
At historic trends to date, China and India will consume ALL Available( Oil) Net Exports in 15 years by about 2028. Global public debt has doubled in the last decade and fuel prices skyrocketed to as high as the economies could bear. Those “hidden” trends promise severe fiscal consequences far before any thermageddon or ice age.
See ASPO-USA http://peak-oil.org/2013/09/the-export-capacity-index/
Actuary Gail Tverberg at OurFiniteWorld.com has numerous presentations with further sobering evidence for the strong of heart. Now how do we provide enough liquid fuel to keep transport and our economies moving? (PS Shale oil is not a long term answer.)
I vaguely recall Warmists have pointed to NH declining Spring snow extent since 1967. If this starts to go up, for whatever reason, then start worrying.
Winter snow extent upward trend since 1967.
Autumn snow extent slight upward trend since 1967.
Jimbo says:
October 18, 2013 at 12:22 pm
No worries. With nuclear fusion power, people can just point giant blow driers at the accumulating snow during the next Less Little Ice Age Cold Period, c. AD 2650.
Willis (or anyone),
Why are the oceans outside the tropics mostly negatively correlated? (eg. yellow / green / blue) while the oceans in the tropics are mostly positively correlated? (eg. orange / red).
One thing even I know is it has nothing to do with snow and ice.
And since we know snow and ice aren’t the cause of the variation of correlation over the oceans, it seems like a huge jump to assume it is the cause over land.
I think the albedo correlation aspect of this blog post needs some major support before it is meaningful.
milodonharlani says:
October 18, 2013 at 11:55 am
Thanks, Milodon. I just downloaded the data from the Epica ice core, and upon re-examination, by and large I have to say that the EPICA data agrees with you … and my point still remains.
Now, when I look at that, I say “Yikes! We could have another ice age at any time”. In part it’s the length of the Holocene, and in part it’s that the other interglacials rose to a peak temperature … and very soon thereafter, they started dropping quickly to glacial temperatures.
The Holocene, on the other hand, rose to a peak, but has only been dropping very slowly. It has maintained a fairly flat plateau for a long, long time now. I see nothing in the historical record to indicate that we couldn’t enter another ice age tomorrow …
w.
There is a classical paper which calculated astronomically that the next ice age is not due for 50000 years.
Berger A and Loutre MF (2002) An exceptionally long interglacial ahead? Science 297 (5585): 1287-8
David L. Hagen says:
October 18, 2013 at 12:12 pm
Like I said … folks love to obsess about claimed future disasters a couple of decades away, and David, your post just proves my point.
Me, I’ve been listening to Peak Oilers since King Hubbert first published his predictions in 1956. According to them, global doom and disaster has been a couple of decades away for that entire time. You’re just the latest in a very, very long line of failed serial doomcasters saying we should be very, very afraid …
w.
No Willis, it is not a positive feedback. It is a variable response to solar heating. But surfaces do not continue to become infinitely black (nor do they start as perfect reflectors)
It is this sort of sloppy use of scientific terms that exasperates me. There is no positive feedback anywhere in the climate system – that is a misapplication of the term positive feedback by James Hansen and other equally deluded people. From unphysical “positive feedbacks” programmed in to climate models come many of the most preposterously scary climate stories that many here rightly lampoon.
If there were any positive feedbacks in the climate system we would all be dead.
Willis Eschenbach says:
October 18, 2013 at 11:33 am
***
My point remains. By all astronomical Milankovitch calculations, we should be falling back into an ice age somewhere around now. To date there’s no sign of it, which is good … but there’s always tomorrow.
As much as I dislike pointing to anything as a “trend,” if you consider the “trend” in temperatures (based on ice core proxies) since the peak temperatures of the early Holocene the overall pattern has been steady, gentle cooling. So, the signs may in fact be right there in front of us all. It is probably worth considering that no interstadial has been identical in length, degree or “shape” to any other.
Hans Erren says:
October 18, 2013 at 12:44 pm
Hans, good to hear from you. That is indeed an interesting paper, saying that we’re at the low end of the 400,000 year eccentricity cycle, and thus the interglacial might be much longer.
So … the bad news is, there’s no bad news about ice ages to worry about?
Dang … I was hoping that the coming ice age would drive the population bomb folks from the headlines …
All the best,
w.
Mostly beneficial?!?! Willis, I will take the extra step and say man’s release of carbon into the atmosphere is the single greatest thing we have ever done for this planet, by far.
Snow … heh … in Kansas north of Dodge City according to the operator I talked with on 40 meters this morning using an antenna 8 foot square only 6 feet above ground at its lowest point (a tuned QW loop fed with a ferrite xformer next to the cap; input Z of the actual loop about 22 Ohms and a flat 1:1 match at the tuned freq with the xformer) …
.
Willis Eschenbach says:
October 18, 2013 at 12:38 pm
The typical pattern is for interglacials to achieve their peak warmth early, then decline toward the next glacial. That’s what the Eemian did & Holocene is doing, for instance.
But they’re all different, varying in duration for example from ~8000 to ~31,000 years. Of course no one can know how long the Holocene will last. It might come to an end in 390 or 39,000 years. My guess is more like 3900 years, but that’s just from extrapolation of the past 5000-year cooling trend, which might not work any better than did IPCC’s extrapolation of one decade’s warming out to twelve.
It is just weather, yet so much fun to post this on the CO2 fear blogs.
They are skiing today at Arapaho Basin Col.
http://www.arapahoebasin.com see web cams for the lines .
It’s snowing in Dodge City as we speak. There is at least one geo- engineering scheme which involves releasing large amounts of sulfur dioxide in order to form clouds and thus increase albedo.. SO2 isn’t soot, but is another pollutant which we’ve worked to curtail.
@Willis: “Hans, good to hear from you. That is indeed an interesting paper, saying that we’re at the low end of the 400,000 year eccentricity cycle, and thus the interglacial might be much longer.
So … the bad news is, there’s no bad news about ice ages to worry about?
Dang … I was hoping that the coming ice age would drive the population bomb folks from the headlines …”
Unfortunately, given the past record for the last million years, there have been 10 major glaciation periods lasting from 80-95,000 years, and each one occurred when earth’s eccentricity was low. The only Melankovitch cycle that is keeping away the glaciation now is the obliquity, for precession and eccentricity are favouring glaciation. We have from tomorrow to maybe another thousand years or so, but it will come. That paper, I believed nattered on about the impact of C02. Well, if C02 has a significant impact on climate, then I retract my above analysis.
JimS says:
October 18, 2013 at 1:23 pm
You’re correct. Eccentricity has just started to dive, headed for a major low in about 30,000 years:
http://www.jgiesen.de/kepler/eccentricity1.html
Interesting and timely, thanks Willis.
(We just got our first cold front this week. Average daily temp has dropped 22ºF.)
If you break the snow data down season by season you’ll find some curious behavior that figure 3 makes it hard to see. Namely, while figure 3 describes the residuals from the year length interval smooth and the *average* season cycle as “random” in point of fact it has a significant non random component: some kind of change in the seasonal cycle-although it is much smaller than the season cycle itself. Look at the graphs they have for each season: winter trending slightly up, fall slightly up, spring noticeably trending down. I think summer also shows a down trend, but for some reason the site doesn’t have a graph for it.
What does it mean? Heck if I know!
@Willis: How does CERES measure albedo? I was just looking it up and found “top of atmosphere” mentioned. I sure don’t know the method and potential drawbacks. Is there a nice primer on the method?
Willis, how do you get the full CERES dataset? I would like to check a most curious claim, which, if true, tells us something very important about the way terrestrial albedo is regulated. It also indicates a hidden symmetry, utterly missing from computational climate models. As it is a common feature of them, it is not only about implementation, but a lack of understanding of physics they are supposed to be based on.
Symmetries observed in nature are usually our best guide to simplify theories.
Journal of Climate, Volume 26, Issue 2 (January 2013)
doi: 10.1175/JCLI-D-12-00132.1
The Observed Hemispheric Symmetry in Reflected Shortwave Irradiance
Aiko Voigt, Bjorn Stevens, Jürgen Bader and Thorsten Mauritsen
THis is another chart where I would have reversed the color choices. Blue for cooling, red for warming.
JimS says:
October 18, 2013 at 1:23 pm
Obliquity of the ecliptic (ε), or axial tilt, during the Proterozoic Snowball Earth episodes might have been shockingly large (although less than right after the hypothesized Moon-creating impact):
http://www.sciencedirect.com/science/article/pii/001282529390004Q
“For ε > 54°, climatic zonation and zonal surface winds would be reversed, low to equatorial latitudes would be glaciated in preference to high latitudes, and the global seasonal cycle would be greatly amplified.”
Don’t know how well this hypothesis has stood the test of time.
Seems like there’s an easier way. Somewhere north and east of Great Slave Lake, find a stable patch of high-summer snow/ice in a hollow, not in a shadowed river valley, not in a north-side mountain snowfield. If you can find one (there may not be any such), just come back every summer and photograph it. You may find it at the boreal forest tree-line.
If you can’t find any such stable summer snowpatch, there’s nothing to worry about yet. From tiny acorns do mighty oaks grow.
“So … would it not be truly ironic if pollution, in the form of soot and brown carbon, were all that has been holding off another ice age? And wouldn’t it be a cosmic joke if our efforts to clean up soot and brown carbon pollution were the straw that broke the back of the Holocene, and ushered in the new ice age?”
That was the background plot for the novel Fallen Angles (Niven, Flynn, Pournelle). The Warmistas & Greens had won the war against fire, and the glaciers began marching south once again. Quite prescient, having been released way back in 1991.
This is a good link for developing snow cover and the historical data does seem to suggest increasing periods of above average cover in recent years:
http://moe.met.fsu.edu/snow/
Hi Willis,
While some places north of the Equator have early cold, parts of Oz have had early warm and bushfires. The episode near Sydney is not over, but already we have had multiple assertions that global warming is the cause. A classic case is this on a University/CSIRO/Met Bureau blog named “The Conversation”, http://theconversation.com/sydney-fires-caused-by-people-and-nature-19327 The blogger wrote –
………………………………..
Mike Hansen, Mr
From one arm of the Murdoch newspaper empire “EXTREME weather events, including destructive bushfires, will become more frequent as a result of climate change, according to scientists working on the latest Intergovernmental Panel on Climate Change report.
The scientists behind the fifth assessment report from the United Nation’s climate science panel, which is due out later this year, have met this morning in Hobart. Scott Power from the Bureau of Meteorology, who is serving as a coordinating lead author in the report, said temperature increases in Australia will accelerate if emissions are not curbed in the next ten years.”
http://www.theaustralian.com.au/in-depth/bushfires/extreme-bushfires-to-hit-more-often/story-fngw0i02-1226554168018#sthash.8Istt1w2.dpuf
From the shock jock arm
“The Greens MP infuriated many when he tweeted that “Tony Abbott’s plan means more bushfires for Australia & more pics like this of Sydney”. The article includes this tweet from a clueless climate science denier troll who was among the herd of clowns who lined up to abuse Bandt. “You are a pimple on the arse of a snake” That apparently passes for news among this group of shock jocks masquerading as journalists.
http://www.heraldsun.com.au/news/national/greens-mp-adam-bandt-tries-to-make-political-mileage-out-of-fires/story-fni0xqrb-1226741900565
Perhaps the staff writers responsible for that drivel should be forced to read their own newspapers – that it indeed would be cruel punishment.
…………………….
Acknowledgement goes to blog lead story author Professor Ross Bradstock; and to Mike Hansen, contributor.
…………………….
While I would like to respond, I’ve been LOCKED OUT by the moderators – after 3 snips wherein I gave references to science that is not agreeing with the Party Line.
…………………….
This is a call for you many readers to hop in and put the case that I cannot. As many of you as possible. Protest both censorship and the Hansen blog above, if your science knowledge suggests a reply is needed. (The Bradstock lead article is quite balanced and not the problem). How about a strong rally round?
The Milankovitch insolation theory is not correct. There are at least 7 specific observational paradoxes to support that assertion. For example the forcing mechanism that ends interglacial periods causes cooling at both poles. As insolation at the two poles is 180 degrees out of phase, the southern pole cools when insolation is maximum in the southern hemisphere. Interglacial periods end abruptly not gradually. There is evidence of cyclic abrupt climate change in the paleo record. The mystery is what is physically capable of causing cyclic abrupt climate change. Insolation changes at 65 N are not the cause of the glacial/interglacial cycle. The cause of the glacial/intergalacial cycle is what causes Heinrich events. The confusion is the orbital configuration at the time of the Heinrich event amplifies the mechanism.
The planet is currently in the orbital configuration that amplifies the actual cause of the glacial/interglacial cycle. It appears we are going to be able to observe what causes a Heinrich event. Observational evidence to support that assertion will be 1500 cycle cooling, record Arctic sea ice, record Antarctic sea ice, and record cold winters in the Northern Hemisphere. The 1500 year cycle cooling is due to Maunder minimum solar magnetic cycle modulation of planetary cloud cover. This 1500 year cycle will be particularly rapid as there was a relate mechanism that was the ion modulation of planetary cloud cover. The physical cause of the Heinrich event follows the 1500 year cycle cooling.
http://earthobservatory.nasa.gov/Newsroom/view.php?id=24476
Glacial Records Depict Ice Age Climate in Synch Worldwide
“Because the Earth is oriented in space in such a way that the hemispheres are out of phase in terms of the amount of solar radiation they receive, it is surprising to find that the climate in the Southern Hemisphere cooled off repeatedly during a period when it received its largest dose of solar radiation,” says Singer. “Moreover, this rapid synchronization of atmospheric temperature between the polar hemispheres appears to have occurred during both of the last major ice ages that gripped the Earth.”
http://en.wikipedia.org/wiki/File:Five_Myr_Climate_Change.svg
http://en.wikipedia.org/wiki/Milankovitch_cycles
Milankovitch cycle Problems (William: In your face anomalies which indicate theory failure.)
2.1 100,000-year problem
2.2 Stage 5 problem
2.3 Effect exceeds cause
2.4 The unsplit peak problem
2.5 The transition problem
2.6 Identifying dominant factor
http://www.agu.org/pubs/sample_articles/cr/2002PA000791/2002PA000791.pdf
The 41 kyr world: Milankovitch’s other unsolved mystery
As I have stated there is a very impressive set of mature investigated astronomical anomalies that support the assertion that there are fundamental errors in the stellar model which explain past and current correlations to solar magnetic cycle changes.
http://www.esd.ornl.gov/projects/qen/transit.html
According to the marine records, the Eemian interglacial ended with a rapid cooling event about 110,000 years ago (e.g., Imbrie et al., 1984; Martinson et al., 1987), which also shows up in ice cores and pollen records from across Eurasia. From a relatively high resolution core in the North Atlantic. Adkins et al. (1997) suggested that the final cooling event took less than 400 years, and it might have been much more rapid.
Until a few decades ago it was generally thought that all large-scale global and regional climate changes occurred gradually over a timescale of many centuries or millennia, scarcely perceptible during a human lifetime. The tendency of climate to change relatively suddenly has been one of the most suprising outcomes of the study of earth history, specifically the last 150,000 years (e.g., Taylor et al., 1993). Some and possibly most large climate changes (involving, for example, a regional change in mean annual temperature of several degrees celsius) occurred at most on a timescale of a few centuries, sometimes decades, and perhaps even just a few years.
Albedo and the Milankovich ( incident TSI ) cycles undoubtedly have something to do with glaciation but so does the absolute quantity of snow fall. The more you get the longer it lasts here in the mountains, ceterus paribus. And, of course ceterus is rarely paribus. But all those other variables involved in causing large quantities of snow are also an issue. We get perennial mountain glaciers with consecutive high snow fall years. Summer cloud cover (albedo) helps a great deal in causing them to last through the summer.
Climate is, in the end, chaotic except when viewed in the geologic time frame and then it is cyclical but still not predicable in any useful sense. Too many unkown, or at least unquantified, variables ie impacts and volcanism just to name a couple that are at present not only unkown but unknowable in the future sense.
“In the red and orange areas, which are mainly in the tropics, the albedo goes up as temperatures rise. This is generally because clouds form as temperatures rise, reflecting more sunlight and cooling the earth.”
That’s a contradiction, you cannot have a temperature rise, and cooling. We could simply say that the tropics get more cloudy as they warm.
“In the blue and green areas, on the other hand, the albedo goes down as temperatures rise. Over the extratropical land, much of this change is from snow and ice. As the land warms, snow melts and the albedo goes down.”
There is an awful lot of temperate zone land there that is blue that never or hardly ever gets snow, that must be just down to diminishing cloud cover.
John A says:
October 18, 2013 at 12:52 pm
Mmmm … we need to distinguish between a couple of things.
First, there can be (and are) individual positive feedbacks in the climate system. The important issue is the net feedback, the sum total of all the positive and negative feedbacks.
Next, your idea that any amount of net positive feedback would kill us all from runaway heating is not correct. In fact, that only happens when the feedback factor is greater than 1. As an example, consider a feedback factor of + 0.5.
If the input is say 16 units, a feedback of +0.5 adds another 8 units to the total output. Of course, there is feedback on that new 8 units, which gives us 4 more units. Feedback on that 4 units gives 2 more units, feedback on that gives 1 more unit, and on ad infinitum.
The final result, therefore, will be 16 + 8 + 4 + 2 + 1 + 0.5 … which is 32. In general, the final state of a no-gain system will be the input times (1 / (1 – feedback)). So if the feedback is +0.5 as in the example, the final state is the input (16) times (1 / (1 – 0.5), which is 16 * 2. Runaway feedback only occurs when the feedback factor is greater than one.
Please note that I agree with you that it is highly unlikely that the net feedback is positive …
w.
The problem with atmospheric composition (as opposed to mass) being permitted to alter the energy balance would mean that there would need to be a permanent negative feedback of 1 in order to retain long term energy balance with energy coming in from the sun wouldn’t it ?
Ulric Lyons says:
October 18, 2013 at 3:39 pm
They do … but that fact of increasing clouds reduces the warming. Now, something that reduces the warming is usually described as having a “cooling effect”, as in the sentence “Increasing clouds have a cooling effect on the daily temperature rise”.
I hate this stupid semantic argument about “warming” and “cooling”. In all cases, there is an implied “relative to the condition without them” that strict grammarians seem to ignore completely. Here are a few examples:
We say the clouds have a cooling effect in the tropics because it ends up cooler than it would be with no clouds. We say the greenhouse gases warm the earth because the earth is warmer than it would be with no GHGs. We say a blanket warms us in bed because it’s warmer than it would be without a blanket. We say that putting fins on an engine cools the engine because it ends up cooler than it would be without the fins.
Now, a strict grammarian would object to all of those uses of “warms” and “cools”. I get told things like “A blanket can’t warm you, it’s not a source of energy”“. I know, but that’s how the language is used, and fighting the way a language is actually used is a futile quest.
It is that implied clause, “than it would be without them”, that you and other strict grammarians are missing out on in this and similar cases.
w.
Ulric Lyons says:
October 18, 2013 at 3:39 pm
An interesting issue, Ulric. To the diminishing clouds I’d add the loss of plant cover in the fall. The plants are very good at absorbing sunshine, they all have pretty low albedo compared to bare ground.
I’d also include frost. Lots of places which don’t get snow often get frost.
w.
Willis Eschenbach says:
“They do … but that fact of increasing clouds reduces the warming.”
OK you could say that they dampen the warming, but without any warming, there would be no cloud increase.
Snow insulates the ground, lack of snow does the reverse (at least in Chicago).
A blanket of snow (6-12″) will keep the ground warm enough to dig with a shovel, a lack of snow lets the ground freeze and requires a pick to dig even 3″ deep (I know from years of experience).
Was all the moisture/storm tracks pushed south of the area leaving clear skies to let whatever heat remained radiate thru clear skies ?
Whatever it was, it all came together in 1996, scared the hell out of my boss/mentor.
He was a civil engineer who worried that the sewers he design/built might freeze.
http://articles.chicagotribune.com/1996-02-02/news/9602020132_1_frost-pipes-near-record-low-temperatures
I wonder if that much frost slows down the spring?
Mmmhhh. Peak Oil. Now M. Hubbert was a smart dude, and based on what he saw in the ’50s, we were running out of gas (pun intended). He never envisioned directional drilling, fracking, and sucking oil out of rocks the well logs might have suggested were “wet” but all other indications said were unproductive. And, that doesn’t even begin to account for the fact that most fields, under primary production, never gave more than about 50% of potential yield, and many far less than that. A worthwhile exploration program might be to go back to old fields, and drill them differently, and frack them, and get more. Once I attend a talk at COFRC (Chevron Oil Field Research Center) in which an engineer proposed “mining” old giant fields: get under them, drill really big holes up into the producing zones, and “milk them” so to speak. Half or more of the oil ever discovered that was economic in the time of discovery has not been produced. That’s trillions of barrels, and there is all the new stuff yet to exploit, or even, identify. Peak Oil is way down the road.
There is no snow here in Brisbane. This proves Global Warming is real. We’re doomed.
Hmmmmm. Albedo. Light scatter. I wish I had eyes that could see into the IR. I have worked on a lot of light scatter meters in my time. None of them however have attempted to measure scatter in the IR. But I do know that light scatter for ice (ie. snow) and water based clouds must be vastly different because the packing density/interparticle distance of each is quite different. More importantly both ice and water droplets interact with the incident IR light differently because they have different extinction coefficients, so warm differently. And then there is the grazing angle. . . . you can readily see rainbows in water droplet clouds (n=1.31), while ice crystal clouds (n=1.33) although they produce the effect, happen at different angles.
In any case albedo change is one of those “rapid onset” emergent phenomena. Both snow and white puffy clouds appearing, must dramatically change the radiation balancing equations when they are present vs when they are absent, and don’t easily drift back to the prior state without a “snap” energy change, because both, when they appear, happen when latent energy changes occur!
Good thoughts as usual, Willis. Your writing never fails to make me think.
Willis Eschenbach says:
“To the diminishing clouds I’d add the loss of plant cover in the fall.”
What regions in particular?
Willis
With your passion for data, may I suggest that you actually LOOK at the oil production data by State and Country and analyze it.
Global conventional crude oil production effectively stopped growing in 2005, after having grown about 1 million bbl/day every year for 20 years. (Small increases since then are primarily non-crude oil).
See Economist James Hamilton documents how oil production in every US State has been following a Hubbert type curve, with almost States (regions) having already past peak conventional crude oil production.
Refusing to look at the data will not make it go away. By Adam Smith’s law of supply and demand, the ~10X increase in the price of oil over the last decade is not due to an abundance of liquid transport fuel!
“Oil Prices, Exhaustible Resources, and Economic Growth,” in Handbook of Energy and Climate Change, pp. 29-57, edited by Roger Fouquet. Cheltenham, United Kingdom: Edward Elgar Publishing, 2013. Working paper version here.
“Historical Oil Shocks,” in Routledge Handbook of Major Events in Economic History, pp. 239-265, edited by Randall E. Parker and Robert Whaples, New York: Routledge Taylor and Francis Group, 2013. Working paper version here.
40 of 54 countries have already peaked conventional crude oil production. Mazama Science shows export data of individual countries.
The International Energy Agency 2012 projects unconventional oil production in the US will peak around 2020 and not exceed the US peak of conventional oil in 1970.
With current oil depletion rates and low economic growth, the cost of developing replacement fuels over the next 40 years at current prices will be about $100 trillion dollars. $100,000,000,000,000!
No small change. Climate change pales by comparison.
Willis Eschenbach says:
“To the diminishing clouds I’d add the loss of plant cover in the fall.”
But surely that will give more albedo not less?
Variable response vs.. positive feedback, thanks to John A. Strictly technically, there is no feedback here, a feedback being defined by Wikipedia as requiring a loop. Here we consider the albedo and temperature as two independent variables.
Nitpicking aside, there is a theory of LINEAR feedback systems. John A. is correct that both snow deposition/thawing or cloud creation/dissipation (or a displacement by winds) has a highly nonlinear effect on temperature. A linear approximation probably won’t work in these cases.
I think you will find that ice ages progress slowly, that is, glacially slowly. So looking for ‘when the next ice age is coming’ is like watching the tide come in, it’s pretty gradual and boring.
Note that the world has been cooling for the last 10,000 years or so, which may be the general rate that will eventually lead to a greater and greater amount of ice. The LIA was probably the coldest in the last 10,000 years.
Also, some scientists have proposed the ‘long warmth of the Holocene’ as compared to previous interglacials as being due to human factors, namely agriculture (which has caused an increase in c02 levels, according to some, since the beginning of agriculture) and land clearing. An interesting idea, but I don’t actually buy it, as the amount of land clearance has not been that great, and I don’t think agriculture hasn’t greatly impacted c02 levels of that c02 has had much effect anyway. I also think that the purported ‘long warmth of the Holocene’ may be in part a function of better data in the last interglacial compared to previous ones, giving a recent warm bias. (The same problem that crops up with the lack of data in the MWP).
thingadonta says:
“I think you will find that ice ages progress slowly, that is, glacially slowly. So looking for ‘when the next ice age is coming’ is like watching the tide come in, it’s pretty gradual and boring. ”
“The Younger Dryas was an abrupt cooling event that took place between 12,800 and 11,500 years ago in the midst of the warming that followed the Last Glacial Maximum. Recent work suggests that the onset of the event occurred incredibly rapidly, possibly in a decade or less, and the termination of the event was equally sharp.”
https://www.e-education.psu.edu/earth103/node/640
Willis said:
“Runaway feedback only occurs when the feedback factor is greater than one.”
Larger or smaller than – 1 surely ?
Unless the initial forcing is cancelled completely there will be a permanent imbalance at ToA and loss of atmosphere eventually.
Less than – 1 and the initial forcing will accumulate a surplus indefinitely.
More than – 1 and the initial forcing will accumulate a deficit indefinitely.
Remember that, come what may, energy in and out at ToA has to be stable in the very long term.
There is no room for anything other than a – 1 feedback if there is any kind of thermostat.
There is room for cycling around the mean due to the fluid nature of air and water but that is all.
Willis Eschenbach says:
October 18, 2013 at 11:33 am
By all astronomical Milankovitch calculations, we should be falling back into an ice age somewhere around now.
Ehh. Where you got this?
Eccentricity: going down and will not go up beyond present level over 100 thousand years, obliquity: dtto – going down and will not go up beyond present levels ~100 thousand years, precession index low and will not go up 50 thousand years, 65N insolation: drift up expected due to precession cycle, will not go down ~20 thousand years, insolation of ocean due to precession cycle: almost highest possible (highest in MWP)…
So I really wonder what all Milankowitch calculations showing something to the meaning “we should be falling back into an ice age somewhere around now” you mean.
“By all astronomical Milankovitch calculations, we should be falling back into an ice age somewhere around now.”
It looks like inslolation rises again in 3000-5000 years:
http://www.leif.org/research/Solar-Insulation-Cycles.png
Willis: ” As an example, consider a feedback factor of + 0.5.”
Yes well. There’s ‘feedback,’ ‘feedback,’ ‘feedback factor,’ and ‘feedback factor.’ With all duplications intentional. In the happy instaland of calculus the feedback factor of an amp is input/output; with loop gain being the reciprocal. In uses from people that hate children and hydrocarbons, ‘feedback’ is any non-zero difference between a proposed input perturbation and any know output pertrubation. Without any regard as to whether there exists an amp at all. Where an amp is just a governor sitting in the feedback path.
A feedback factor as you described it is not a feedback factor. It is a step wise explanation of how the governor hits on bistability or hysteresis. It’s isn’t a bad explanation, but it’s the sort of thing John A was on about. That any positive feedback, as in the per-step feed, without a governor goes to infinity and beyond. It’s a Toy Story.
Which is also not what John A expressly stated. So he may be guilty of his own foul as well. I mention it as the only solution for his complaint, under the assumption that he knows what he’s on about.
And just for the note: Amps are always ‘powered’ in the electronic world. But it is only necessary that they perform a conversion process at some point. That items in cannot be treated fungibly with items out. With CO2 we may treat IR photons fungibly since one in is one out, and we could hardly care nor tell the difference between them. But the surface absorbs IR, converts it in a lewd atomic bump n’ grind, then emits a broad spectrum. We cannot say that each IR in is an IR out. They simply aren’t fungible.
With respect to the climate, as climate, the feedback fractor is Watts_in/Watts_out. Which need not be unity in any given time step, but must average out to unity across all time steps. The AGW apocalypta is predicated on the idea that the feedback factor is given by Watts_in/Temperature_out. But that’s not an amp. It’s a token, at best, of talking about the state of the governor in the amp.
Ulric Lyons says:
October 18, 2013 at 4:48 pm
Agreed, Ulric … but since the temperature is falling, once again it’s a negative correlation (blue/green).
w.
Willis Eschenbach says:
“I’d also include frost. Lots of places which don’t get snow often get frost.”
That often melts soon after sunrise, more so if there is less cloud cover of course.
Willis Eschenbach says:
“..but since the temperature is falling, once again it’s a negative correlation (blue/green).”
Here is what you said in the article:
“In the blue and green areas, on the other hand, the albedo goes down as temperatures rise.”
“Do I think that’s the case, that soot is all that is keeping the next ice age at bay? Y’know … I truly don’t have a clue whether that’s true or not. That’s one beauty of climate science, that there are so many mysteries.”
= = = = = = = = =
Spot on Willis (± 95%), many are those who have been blaming the soot for the melting of the earth’s permanent snow and ice. And it could be true. And good on you for making some speculations about it on paper.
One other thing which I have been looking at, when it comes to pondering “the end of this present Inter-glacial period” we enjoy just now is; what was the long (tall) stone structures called “Cleopatra’s Needle” used for in ancient times if it was not for measuring (or keeping “a check on” the Earth’s axial tilt? What if Milutin Milankovitch’s theory is slightly wrong when it comes to the ‘Tilt (and Wobble) of the Earth’s Axis’?
The theory says that the Earth’s axis fluctuates between 22 and 24.5 degrees every 41000 years. – The present tilt is around 23.5 degrees. The “Wobble means that if you put a cine-camera looking straight up on the North Pole it would film a complete circle of the stars above in 23.000 years (Oh boy, that,s some camera that is)
The theory also says that the Earth’s orbit pulsates, becoming more and less elliptical every 100.000 years and every 433.000 years.
If you look up Ice-core graphs (even the one Al Gore used in his Inconvenient Truth slap-stick film) you’ll see that there was indeed a very long interglacial period, a bit colder than the present one maybe – but just as long (durable) or maybe even longer still.
So, Milankovitch who had never seen an Ice Core-graph is on pretty solid ground, but even so – “Why do the Sunlight shine through a certain “hole” in the walls of, say Stonehenge in UK and it hits a certain spot on an other wall on a certain time of a certain day of every year, just as it must have done 7.000 years ago when it was first built, if the Earth is continually changing its axial tilt and wobble?
Anyway, what happens at the Equinoxes on September and March the 21? – Well, that’s when Spring and/or Autumn happens in both/either Hemisphere/s, because the “Axial Tilt” (AT) is neutral, just as it would be all the year round if the ‘AT’ was 0 or just a few degrees.
So, what if the “Cleopatra’s Needles” were products from a time just after the “Younger Dryas (YD) frost period, – and the YD came about because the Earth is not as stable on its axis as we assume? Maybe it can vary much more wildly than we think. Maybe the Axis is quite upright for 100.000 years or so, keeping the “Summertime” away from both Hemispheres “permanently”, then what?
I truly don’t have a clue whether the above is true or not, but it could be. – And it could also be “laughed out of Court”. Hope none of us – living today – will find out for sure.
Hi Willis and thank you for your work.
Assume first that I am concerned about the advent of major global cooling within the next thousands of years.
My question is this:
IF we were faced with an impending global Ice Age, could we defer it indefinitely by deliberately spreading soot over very large areas of snow?
Are there any better means of deferring an Ice Age?
Best personal regards, Allan
[Please do not say add more CO2 to the atmosphere – I’m pretty sure that will not work – ECS is too low, if it exists at all. :-} ]
Phase 3 initiated.
Just a minor nit, and not unique to Willis’s writing, and doesn’t detract at all from what he wrote here.
Unless I’m mistaken, the earth has been in an “ice age” for several hundred thousand years. During that time, we have gone through several periods of “glaciation”, interspersed with relatively shorter “interglacial” periods. So it’s not pedantically 😉 correct to say that we came out of an “ice age” about 10,000 years ago, and will go back into another “ice age” sometime in the future. I don’t think anyone really knows if the current “ice age” has ended yet, or if it ever will end. Assuming the current “ice age” hasn’t ended yet, we are very likely heading toward another period of “glaciation”.
Ulrich Lyons: Yes but the Younger dryas was likely not related to the causes of major ice ages, its more likely a blip.
Hey Poptech. Anthony has been more than tolerant regarding your recent meltdown. You’re looking like you want to graduate from troll to stalker. Do yourself favor and go chill..
The initiator of the next ice age is when the snow does not melt in the summer on Ellesmere Island and the sea ice does not melt out at 75N.
The projections are this will continue for as much as 125,000 years (not 50,000 but 125,000 years).
At Eureka Nunuvut Canada at 79.5 degrees north (which has a world-class weather research station staffed by several scientists), the snow left on June 18th and didn’t permanently return until August 14th. And this was a relatively cold summer at Eureka, probably the coldest in 20 years.
That still leaves 57 days of no snow or nearly 2 months in a relatively cold year. Much cooling is required to drop that to Zero days and kick off the next ice age. Get used to the interglacial because it will be the longest one in the last 2.7 million years.
http://climate.weather.gc.ca/climateData/dailydata_e.html?StationID=1750&timeframe=2&Year=2013&Month=6&cmdB1=Go
http://climate.weather.gc.ca/climateData/dailydata_e.html?StationID=1750&timeframe=2&Year=2013&Month=8&cmdB1=Go
http://www.cpc.ncep.noaa.gov/products/global_monitoring/temperature/tn71917_1yr.gif
“I’m keeping an eye on the snow extent ”
The “canary in the coal mine” is the Athabasca glacier in Canada. When it advances, watch out. It is thought by some that this is where the western ice sheets of North America originated and then spread down across Alberta. The snow field from which the Athabasca originates feeds several glaciers and feeds into the Arctic, Pacific and Atlantic oceans. Glaciers from this snow field can stretch to Washington State and/or to Montana.
Watch the Athabasca glacier. As long as it is stable or in retreat, we’re doing just fine.
David L. Hagen says: October 18, 2013 at 4:48 pm
With current oil depletion rates and low economic growth, the cost of developing replacement fuels over the next 40 years at current prices will be about $100 trillion dollars. $100,000,000,000,000! No small change. Climate change pales by comparison.
Nuclear.
By then we will all think it is a great idea.
John A said in part (Oct 18 at 12:52 PM):
“If there were any positive feedbacks in the climate system we would all be dead.”
This is wrong. Positive feedbacks between 0 and 1 are just amplifications.
Willis at 3:53 PM gave the right answer. As he says, if the feedback factor is g, the amplitude response of the system is 1/(1-g). That is, the output is multiplied by g and added to the input, and this changes the input to output gain as 1/(1-g). Thus:
if g<0 (negative feedback) the result is an attenuation (damping)
if g=0 (no feedback), there is no change
if 0<g1 (positive feedback exceeding unity) then you have a run-away.
So, as an example, for g=2/3 (a positive feedback) the amplification is 3. The alarmist claim an amplification of 3 for the climate sensitivity. This is very unlikely to be the case, but it is not a run-away.
Sorry – the inequality sign apparently messed up my posting at 8:18 PM. Here it is in English!
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John A said in part (Oct 18 at 12:52):
“If there were any positive feedbacks in the climate system we would all be dead.”
This is wrong. Positive feedbacks between 0 and 1 are just amplifications.
Willis at 3:53 gave the right answer. As he says, if the feedback factor is g, the amplitude response of the system is 1/(1-g). Thus:
if g less than 0 (negative feedback) the result is an attenuation
if g=0 (no feedback), there is no change
if g greater than 0 and less than 1 (positive feedback less than 1), there is a gain (an amplification) but no blow-up.
if g=1 (positive feedback of 1), we have a linear ramp (an accumulator)
if g greater than 1 (positive feedback exceeding unity) then you have a run-away.
So, as an example, for g=2/3 (a positive feedback) the amplification is 3. The alarmist claim an amplification of 3 for the climate sensitivity. This is very unlikely to be the case, but it is not a run-away.
Lynn Clark said @ October 18, 2013 at 7:04 pm
You are correct; “ice age” use in this piece is a colloquialism for “glacial period”.
Willis,
As always interesting and informative discussion follows your posts.
Glaciation mitigation, anyone?
Elaborating on my comment of Oct. 18, 8:30 PM: This is probably not the place to review feedback theory completely, but the two cases of my five where g reaches or exceeds 0 do not give an asymptotic steady state (viewed as a discrete time sequence), as the cases where g is strictly less than 1 do. The result 1/(1-g) does NOT apply.
Having g equal to or greater than 1 is “unphysical”. It would call for infinite energy. In a so-called run-away greenhouse, positive feedback greater than 1 may well exist for a period of time, but soon enough something else will limit the output (perhaps a “governor”, as some suggest, if you like).
For example, I design circuits with positive feedback gains much much greater than 1 all the time (e.g., a Schmitt trigger, a comparator with hysteresis) which very quickly asks for infinite voltage, but has to settle for the maximum the power supply will give (called saturation). Likewise the planet Venus is supposedly in a positive feedback CO2 run-away. Isn’t it just quite hot, but stable? [Perhaps Venus like AL Gore’s deep earth is millions and millions of degrees at this point!]
So perhaps g=1 rather than g=0 is the better point to keep in mind. Thus it may be that John A was using a wrong (or at least different) definition of positive feedback. Also, it may be that John A’s saying “surfaces do not continue to become infinitely black” may be precisely what I am talking about as saturation in an electronic circuit. Thus he likely has that good point.
Thus a true positive feedback mechanism that in addition actually has g greater than 1 may be driven to saturation and thereafter fail to run away (it becomes governed), and NOT kill us all. But it’s still positive feedback that got us there. But going from g=-0.01 to g=0 and then to g=+0.01 is smooth. Going from g=0.99 to g=1.00 to g=1.01 is where the “surprise” is.
The alarmists’ g=2/3 with an amplification of 3 (very unlikely) might a disaster, as would most certainly g=0.99 with its amplification of 100. We need to recognize that some manner of saturation likely cuts in, even for g between 0 and 1. Or even more likely, the NET feedback is g less than 0 (negative), as many here believe.
I agree with Bernie; the system is surely non linear; in that case, under certain conditions, a bigger than one “positive” feed back could create an oscillator (climate larsen?). And precisely we have oscillations…(60 years periodic)…
Bernie Hutchins: “… but has to settle for the maximum the power supply will give (called saturation).”
Sure, and in climate our power supply is insolation. On a climate scale it’s also the signal for the ‘amp.’ But when you have a fancy feed back device that is constant current and constrant signal you call it? A wire.
If you ignore this and start talking about CO2 and IR photons. Which does return a fraction of the IR reradiated from the surface, to the surface. But if more current in (photons of all frequency) to the surface guarantees more IR out the surface? Then tf the ppm of CO2 is enough to have any effect at all, then the effect is a Schmitt trigger in every case. That’s a full on Venus in Jersey, during winter.
Go from there and remember by loose analogy that temp = volts. Such that climate feedbacks are postulating gain from a short circuit current input (photons don’t have a temperature) to a voltage output.
Ice/Albedo is a positive feedback forcing in the earth’s climate leading to considerable glaciation of the NH.
If the earth’s atmosphere also contains a positive feedback due to water vapour, would this not cause the earth to completely freeze over during an Ice Age.
In reality is the fact that a snowball earth does not occur prove that the water vapour feedback is in fact negative?
Frequently we read that the global temperature has been warming, sometimes we read that this is a “recovery from the Little Ice Age”.
What part of the Earth was cold in the Little Ice Age, that is warming up now?
That is, where was that “cold” stored?
Alternatively, if that concept is wrong, and if we assume solar input to be constant at TOA, is the warming since the LIA a consequence of fast events such as more frequent initiation of a daily thermostat mechanism?
There are so many options in this climate business that sometimes it is hard to even separate postulated effects that are more static or long-term, from those that are dynamic, varying up and down in the short term, sometimes to give an aggregation.
Then there is the contentious concept of whether earth systems respond in directions to balance an equilibrium, when we don’t now where equilibrium should sit, or why, or if there is one.
Think of all that past research spending. We don’t seem to know answers to simple questions like these.
The main confusion seems to arise from too much emphasis on GHG.
Let’s have more on thermostats, please.
It seems to me that some “feed-backs” are authors of their own demise. For example, the curve of a meandering river gets larger and larger until the river abruptly cuts a straight route, leaving an oxbow lake behind.
In the arctic having ice on the sea allows mild currents to come north under the ice, melting the underside of the ice to a more northerly extent, and allowing swifter break up in the spring. Thus ice is author of an ice-free situation.
Conversely, having an ice-free situation allows water to cool more deeply before it freezes, (right down to the pycnocline according to some,) thus creating 400-foot-deep barrier to warm currents coming north, and increasing the refreeze and retention of ice. Thus lack of ice is author of an ice-cap.
In the end you have a cycle. I have enough trouble with basic math and shudder at the thought of attempting to take on oscillations. My sense is that a certain amount of chaos is involved: A 60-year-cycle may screw up your forecasts by being 58 or 62 years. Therefore I will do what a smart quarterback does when he sees four burly linebackers charging towards him.
I’ll hand the ball off to Willis and let him run with it.
By the way, Willis, thanks for another excellent article.
On Milankovitch & climate variations, Roger Pielke Jr. highlighted the “New Paper “Climatic Variability Over Time Scales Spanning Nine Orders of Magnitude: Connecting Milankovitch Cycles With Hurst–Kolmogorov Dynamics” By Markonis And Koutsoyiannis” , Surveys in Geophysics, 34 (2), 181–207, 2013. i.e., addressing climate persistence statistics and showing climate variations are not “random”. Preprint pdf
Evidence they show from the Taylor Dome suggests that climate has been cooling slowly since the Holocene Optimum about 10,000 years ago.
In “Determining the natural length of the current interglacial”, P. C. Tzedakis et al. Nature Geoscience Letters 8 JANUARY 2012 | DOI: 10.1038/NGEO1358
What a remarkable degree of precision in that prediction!
However, Roy Spencer shows 96% (87 of 90) current CPIM5 model projections from 1979 are hotter than subsequent temperatures (>95% failure).
Consequently, I’ll take Tzedakis et al. with a grain of salt.
Prudent precautions would indicate that we should invest in long underwear companies!
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Willis Eschenbach says:
October 18, 2013 at 12:38 pm
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I say Yikes! too when I look at what the climate is like most of the time. Very variable and much colder than present.
At least glacial periods seem to have significant “moderate” periods when glaciation is not at its greatest extent.
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JimS says:
October 18, 2013 at 1:23 pm
Unfortunately, given the past record for the last million years, there have been 10 major glaciation periods lasting from 80-95,000 years, and each one occurred when earth’s eccentricity was low. The only Melankovitch cycle that is keeping away the glaciation now is the obliquity, for precession and eccentricity are favouring glaciation.
***
Not sure low eccentricity favors glaciation in general — last minimum eccentricity was during the long MIS 11 interglacial.
Thank you Willis for covering this subject in such a thought-provoking way and to the rest of you for some very interesting comments. If I may, I’d like to make a contribution too.
Regarding Milankovitch’s theory that orbital changes have been responsible for the switching between glacial and interglacial periods over the past million years or so, the spacing in time between successive interglacials is of the right order of length and is periodic enough for the temperature variation to be attributable to orbital forcing. But working out exactly how the orbital variation could give rise to this pattern is far from easy.
The changing rate of insolation at 65 deg. north is usually presented as the measure of the degree of orbital forcing, but this isn’t a magic number that can explain everything. Insolation at all latitudes changes over time and the actual degree of forcing would be the result of the cumulative changes in isolation at different latitudes. Insolation at 65 deg. north is used as a proxy because the figures for a single latitude are fairly easy and straightforward to calculate. But it is far from being the whole story and we shouldn’t expect a precise match between the 65-deg. insolation curve and the temperature graph calculated from ice core or other data.
Interestingly, the northern hemisphere undergoes a greater range of warming and cooling throughout the year than the southern hemisphere does. Also, the Earth is at its warmest during the northern hemisphere summer (in July), even though it is at its closest to the Sun during the northern hemisphere winter (in January) at its present stage in the approx. 23,000-year precessional cycle. So the Earth at present warms while it is moving away from the Sun and receiving relatively less insolation, and it cools while moving towards the Sun and receiving relatively more insolation. This is because there is twice as much land in the northern hemisphere than the southern hemisphere, and land warms more in summer and cools more in winter than ocean does. I suppose the overall effect of land works to keep the planet warmer or cooler than the ocean does, but I am not certain this is the case so perhaps somebody could enlighten me on that. Would an Earth with no ocean be warmer or cooler than an Earth covered 100% by ocean?
If the overall effect of having a greater ocean area is more warming, then we may have identified another modest positive feedback mechanism for driving the planet into and out of glaciations, because as the world cools and the ice sheets spread, sea level drops and more continental shelf is exposed leading to a decrease in the surface area of the ocean. Much of this “new” land becomes covered by ice sheets in Europe and North America, but there is also a considerable area in the tropics, particularly in and around Indonesia.
When considering whether the earth is going to warm or cool, we should bear in mind that in order to warm, the earth needs to absorb more energy than it emits. The planet is absorbing and emitting energy constantly, and if we knew how much was emitted and how much absorbed on any given day, month or year, then in principle we would be able to work out how much the planet had warmed or cooled over the said period. In practice, this may be easier said than done, even in the satellite era, but it’s something we should be aware of. In addition, the warmer the earth is, the higher its rate of energy emission will be and so the more incoming energy it needs in order to maintain its temperature. All other things being equal, to remain at the same temperature, hot Earth requires more insolation than a cold Earth.
But all other things are not equal. The main variable appears to be the Earth’s albedo, or reflection coefficient. (As Stephen WIlde points out, the mass of the atmosphere also helps determine the surface temperature, but I haven’t heard anyone suggesting that this has varied very much over the past million years.) So in short, the amount of sunlight reaching the top of the atmosphere and the albedo determine our planet’s surface temperature. I had always assumed GHG’s raised the temperature by about 33 degrees C, because that’s what I’ve always been told. But after reading several of Stephen’s articles I’ve started to question that assumption.
Whoops!
I suppose the overall effect of land works to keep the planet warmer or cooler than the ocean does
=>
I suppose the overall effect of land works to keep the planet warmer than the ocean does
Here are the last 5 interglacials in the SH.
The phase of obliquity and eccentricity were similar 420kyrs ago, similar interglacial as well though longer than present.
http://s852.photobucket.com/user/etregembo/media/GW_08202007_9174_image001-1.gif.html?sort=3&o=18
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Bill Illis says:
October 18, 2013 at 7:36 pm
The initiator of the next ice age is when the snow does not melt in the summer on Ellesmere Island and the sea ice does not melt out at 75N.
The projections are this will continue for as much as 125,000 years (not 50,000 but 125,000 years).
That still leaves 57 days of no snow or nearly 2 months in a relatively cold year. Much cooling is required to drop that to Zero days and kick off the next ice age. Get used to the interglacial because it will be the longest one in the last 2.7 million years.
***
Interesting comments as usual. Be nice to think the glaciation cycle could be broken for some time.
Of course, it’s possible arctic snowfall could become heavier & persist from increased depth & not temperature per say.
ed says:
October 19, 2013 at 8:59 am
Some students of the subject think that MIS 11 is the best fit for the current interglacial. If so, it’s liable to be a long one. But not long enough for the Greenland Ice Sheet to melt.
Tzedakis thinks that MIS 19 is a better analogue for the Holocene:
http://www.clim-past.net/6/131/2010/cp-6-131-2010.html
If so, then we’re headed for another Big Ice Age sooner rather than later.
Ulric Lyons says:
October 18, 2013 at 6:22 pm
Yes, and the albedo also goes up as temperatures fall … it’s negative correlation either way.
w.
Geoff Sherrington says:
October 19, 2013 at 3:56 am
CACA advocates still try to persuade themselves & mislead the public that the Medieval Warm Period & Little Ice Age were North Atlantic regional phenomena. But both were in fact global. The LIA affected the whole planet, as evidence from all around the world shows.
Lynn Clark says:
October 18, 2013 at 7:04 pm
The present longer glacial, shorter interglacial cycle has been going on for about 2.6 million years, not just hundreds of thousands. The periodicity appears to have switched about a million years ago, however.
http://en.wikipedia.org/wiki/100,000-year_problem
The term “Ice Age” is a problem, since it can refer to glacial episodes in general, to the whole of the Pleistocene glaciation specifically or to the glacial phase of one cycle within it or an earlier icy world. Its meaning in each case can be derived from context, if not clearly stated.
milodonharlani says:
October 19, 2013 at 9:18 am
Raymo & Mitrovica conclude that the Greenland Ice Sheet did collapse during MIS 11, but then it was probably warmer as well as longer than the Holocene to date:
http://www.nature.com/nature/journal/v483/n7390/abs/nature10891.html
“Contentious observations of Pleistocene shoreline features on the tectonically stable islands of Bermuda and the Bahamas have suggested that sea level about 400,000 years ago was more than 20 metres higher than it is today1, 2, 3, 4. Geochronologic and geomorphic evidence indicates that these features formed during interglacial marine isotope stage (MIS) 11, an unusually long interval of warmth during the ice age1, 2, 3, 4. Previous work has advanced two divergent hypotheses for these shoreline features: first, significant melting of the East Antarctic Ice Sheet, in addition to the collapse of the West Antarctic Ice Sheet and the Greenland Ice Sheet1, 2, 3; or second, emplacement by a mega-tsunami during MIS 11 (ref. 4, 5). Here we show that the elevations of these features are corrected downwards by ~10 metres when we account for post-glacial crustal subsidence of these sites over the course of the anomalously long interglacial. On the basis of this correction, we estimate that eustatic sea level rose to ~6–13 m above the present-day value in the second half of MIS 11. This suggests that both the Greenland Ice Sheet and the West Antarctic Ice Sheet collapsed during the protracted warm period while changes in the volume of the East Antarctic Ice Sheet were relatively minor, thereby resolving the long-standing controversy over the stability of the East Antarctic Ice Sheet during MIS 11.”
The oldest Greenland Ice Sheet core found dates to ~150 Ka, during the glaciation preceding the Eemian interglacial:
http://blogs.agu.org/wildwildscience/2010/07/31/oldest-greenland-ice-core-recovered/
Very interesting comment regarding man-made emissions countering natural cooling. There is no doubt that environmental regulations have drastically reduced particulate and SO2 emissions from power plants. Both of these constituents in the atmosphere have a cooling affect. So a logical follow on to the post would be that the very regulations that clean our the air could be contributing to future cooling. Perhaps our policy makers should also focus on reducing atmospheric CO2 levels to help speed our way to the next ice age. May God help Canada and the rest of the Northern Hemisphere.
Not sure if I understand it correctly, but do available snow/ice albedo data sets actually publish calculated data adjusted over time for locality and time of year, as well as simple area?
By this I mean, for example, that reflected spring sunshine falling on snow/ice at, say, 70 degrees South would be greater than reflected spring sunshine falling on similar snow/ice at 70 degrees North because the Earth is closer to the sun during the Southern hemisphere summer months.
Yes, it is part of the various Milankovitch calculations, but I’m interested to see data where it is coupled with the actual recent satellite observations to indicate anomalies of how much energy really was reflected. Or does cloud cover make these calculations unreliable?
Willis – not to party-poop, but a year is not 52 weeks, nor is every year the same number of days. Your 52-week average will move about with the location of the ‘missing’ day(s) in the year, and over 40 years, could influence the average by up to +-0.2M from start to finish.
From another angle, WTF happened in 1985 to set the snowcover tumbling? Dates for Pinato and St.Helens don’t seem to match up.
Willis Eschenbach says:
“Yes, and the albedo also goes up as temperatures fall … it’s negative correlation either way.”
You agreed about diminishing cloud cover in the non-snowy regions of the blue-green areas as a likely cause of less albedo with a rise in temperature. A “loss of plant cover in the fall” as you suggested, will do the opposite, it will increase albedo. So I fail to see why you are adding that to the diminishing cloud parameter.
Anybody know if there are any ocean sediment cores close to Greenland for a longer time series temp proxy? Would be nice to compare to vostok to look st hemispheric timing of orbital induced variations.
ed says:
October 19, 2013 at 12:12 pm
Don’t know how close to Greenland you want, but here’s the classic paper on comparison of North Atlantic sediment with GIS ice cores.
http://www.liv.ac.uk/~jan/teaching/References/Bond,%20Broecker,%20Johnson%20et%20al.%201993.pdf
Sediment core locations in the northern Norwegian-Greenland Sea:
http://epic.awi.de/10709/1/Kas1995c.pdf
It looks like Antarctica maybe sending us a message about the near term climate of the world. NSIDC finally updated the data. The Antarctic sea ice has not received the message that spring has sprung. The sea ice maintained it,s growth into early October and experienced one more ‘upward spike’. There was a small downslope afterwards, then over the last 12 days the sea ice broke away from the trend line and went sideways. The line sits well above the trend line. I had made a comment about this possibility in late September.
Anthony Watts, you have a problem. How you deal with this is up to you as it is your blog. IF this was MY blog I would BAN Poptech now. Better to have damage now that greater damage later. Poptech, also known as Andres Khan (among other names), is obsessed and I fear dangerous. This is just a friendly note.
Seems like we’ve started the slow descent into the next glacial already, starting about 3kyrs ago. At least comparing gisp2 and Vostok. On top of it is the 6200yr cycle recovery (min @LIA) and the 1200ish bond cycle, but behind it all the slow decent.
Harmon, know of any sediment cores going back 500kyrs in the NH? Would help the comparison because there opposing cycles at work (obliquity?). The wobble effects the timing and length of interglacial I’m guessing.
Here is a graph of gisp2 and vostok during this interglacial…
http://s852.photobucket.com/user/etregembo/media/GISP2_VOSTOK_INTERGLACIAL.jpg.html?sort=3&o=35
Since there is at the moment quite a lot of ice extant on the planet, would it not be somewhat more accurate to say that we are in an ice age, rather than awaiting the arrival of the next one? There have been periods in the past when there was pretty much zero ice for 10 of millions of years and more. Those periods could be properly referred to as “ice free ages”. It seems to me that we are still in the ice age that began with the Pleistocene, however, lucky enough to be alive during a relative minimum. Thus we await the arrival of the next maximum of the current Pleistocene Ice Age, not the beginning of a new ice age. I hope it’s a long wait. And, I wouldn’t be saddened if in fact all the ice melted and the Pleistocene actually comes to an end finally.
Well I know this is not climate, but rather weather or as we say here (Vermont) weatha related.
I can track a few things related to the weatha, such as:
Cords of Wood burned
Gallons of gas used by the snow blower
Width of bands of the Woolie Caterpillars
Number of Acorns dropped
Date of first southbound geese, etc.
Question is, are any of these metrics any more or less meaningful than anything else we are studying here?
Or mebbe I need to get a grant for this?
/Kinda Sarc,
Jimbo, my name is not Andrew Khan despite your ignorance of all things Internet related. I am only electronically dangerous to people wish me to be banned.
Jimbo says:
October 19, 2013 at 6:02 pm
I agree with you. For whatever reason, perhaps some slight or humiliation that Poptech imagines Willis has publicly inflicted upon him, Poptech appears to have slid from rational blog disputant into the obsessive stalker zone. Such hostility & enmity does indeed carry with it serious risk. Regrettably, IMO there’s not much that the blog’s owner can do about it at this point.
I would urge Willis to look to his outer, middle & inner perimeter home defenses. This might sound extreme, but I’ve seen feuds in the real world spiral into violence. If anything, the Net is even more dangerous, despite lack of physical proximity, due to relative anonymity. Whatever harm Poptech might fantasize beyond contacting periodical editors could be laid off on Warmunistas attacking a “Denier”.
“With current oil depletion rates and low economic growth, the cost of developing replacement fuels over the next 40 years at current prices will be about $100 trillion dollars. $100,000,000,000,000!”
Not to worry. Canceling Obamacare will likely save all this and more in the next forty years.
milodonharlani, Your delusional conspiracy theories are amusing if not bat sh@t crazy.
Two other examples to add to my previous two comments about positive feedback in electronic systems can be made for additional perspective. The first is a run-away limited by a “governor” and the second is an intentional amplification.
First, there is the ubiquitous “feedback squeal in a PA system” that so many writers resort to to “explain” positive feedback. This is said to be sound that comes out of a loudspeaker, finds its way back to the microphone, and whips around again and again. We all know that turning down the gain (volume control) of the amplifier corrects this at the expense of a lower room volume (equalizer circuits are another solution).
It is sometimes said (erroneously) that the oscillation frequency is determined by the distance between the speaker and the microphone. It’s not – it is determined by the largest of the room resonant modes. An acoustic resonance in the feedback path makes the loop gain greater than +1 with a full-cycle of phase shift. Almost always it “clips” slightly resulting in an annoying, but nicely sustained oscillation. This is an example of positive feedback running away to saturation (the max the amplifier can do) but stopping there (governor).
The second example is the wonderfully historic “regenerative radio receiver” invented by Edwin Armstrong, and used as a popular home radio of the 1920’s and 1930’s. It had positive feedback through a “ticker coil” that was sometimes problematic, but fun in hobbyist’s construction when the design was adapted to single transistor circuits in the 1950’s. Here the positive feedback is greater than 0 but less than 1, so is an amplification (which was the whole idea) and there is no saturation.
milodonharlani says:
October 19, 2013 at 8:16 pm
I do not know why Poptech has taken such bitterness and enmity upon himself towards me. I’m sorry to see it, and if it is for some slight or humiliation that I’ve put upon him, he has my apologies.
I disagree completely. My sense is that Poptech has no intention of physically harming me, nothing like that at all. I don’t read him as that kind of guy in any way. Instead, he wants to correct what he sees as misrepresentations of my “credentials” out there in the world.
Curiously, I don’t have a problem with that, other than the spirit in which he is doing it. It’s injurious to a man to internalize that kind of bitterness towards someone else, so I wish he wouldn’t do that do himself.
But I have absolutely nothing invested in how I am described out there in the world. My ideas either stand or they fall on their own. Whether I’m described in some random publication or blog post or web site as a computer modeler or a commercial fisherman is immaterial. The only things that count are the validity of my scientific hypotheses and insights. The strength of the ideas don’t depend on what my day job might be, or what I might have done in the past.
So I’m not opposed to Poptech agitating to correct what he sees as mis-statements. I don’t see them as that, but I’m not concerned about his doing it, I don’t see it as a problem. A google search on “willis eschenbach” brings up a quarter million pages, so it is going to be a long task. He’s more than welcome to do it, I don’t oppose it.
w.
Willis,
You are a class act. Always have been.
Poptech has some personal demons. We all do, to some extent. I like his database; he holds warmists to account.
I am sorry personally, that this has evolved into internecine warfare. Neither one is the enemy. The alarmist crowd is the enemy; they do not believe in science, or in the scientific method, or in anything but politics.
It is a shame that everyone on our side cannot always show a united front. But I suppose that is a facet of human nature…
Poptech says:
October 19, 2013 at 9:32 pm
If you want to see batsh*t crazy, look in the mirror.
You’re already stalking Willis on the Net. To his home is a small step farther.
Willis Eschenbach says:
October 19, 2013 at 10:02 pm
The quarter million pages bit is funny, but Poptech’s cyber-stalking of you isn’t. What some reporter got wrong about you, if indeed it be wrong, could only be so important to a crazy person.
I hope that my suggestion as to where Poptech’s vendetta against you is trending will help him see how truly disturbed & disturbing his behavior is becoming, even if you don’t feel personally threatened by it.
dbstealey says:
October 19, 2013 at 10:10 pm
IMO skeptics don’t necessarily need to show a united front. We should be as critical of ourselves as of CACA advocates. That’s science. But private, personal vendettas IMO have no place either within the skeptical community or between it & “consensus climate science”. I’ve called CACA practitioners charlatans, because they are, but I don’t wish anyone personal harm, no matter how much their lies might be hurting others. Maybe I’m paranoid, but Poptech seems to me to have crossed the line in obsessive pursuit of his great white whale, the citizen scientist Willis.
What is the primary source of all that moisture, do you suppose?
per se, btw.
The obsession with armageddon is entirely fictitious, however, it serves the interests of certain people to instigate such obsesssions.
Why?
Because ‘armageddon’ requires that you DO SOMETHING.
What happens when you do something? MONEY GETS SPENT, LAWS GET CHANGED, INDOCTRINATION OCCURS.
What is the effect of money getting spent, laws changing and indoctrination occurring??
Some people get VERY, VERY RICH.
Religion is a magnificent example of people getting rich in this way. Look at the vast wealth of churches in their heyday (the catholic church today, the Anglican Communion until recently etc). THEY MADE PEOPLE PAY TITHES AND BECAME MR 10%.
‘Peak oil’ was a great scare story because it drove up the price of oil. That made certain Arab Sheikhs and a few MNC shareholders/executives very, very wealthy.
Global warming is a great scare story because Governments spend billions researching it and trying to do something about it. Scientists, green energy people etc etc get bunged a lot of money. They love it.
Long-term risk-free revenue streams is the best incentive for armageddon stories.
All risk managers should investigate this hypothesis ruthlessly before ever agreeing to spend one dime on the latest ‘armageddon’.
***
Brian H says:
October 20, 2013 at 12:12 am
What is the primary source of all that moisture, do you suppose?
***
One that comes to mind is longer autumn ice-free periods in the adjacent arctic oceans that could supplement moisture in storms there. Possible, but not demonstrated so far…
The transition boundaries between glacial periods and interglacials during our current Quaternary glaciation seem sharp to me.
http://earlywarn.blogspot.com/2012/01/more-paleoclimate-vegetation-maps.html
Poptech says:
October 18, 2013 at 7:01 pm
Phase 3 initiated.
Anthony, considering how far across the line he went last time, if this post from Poptech isn’t enough to earn a permanent ban, what will it take?
milodonharlani says:
October 19, 2013 at 9:44 am
The oldest Greenland Ice Sheet core found dates to ~150 Ka, during the glaciation preceding the Eemian interglacial:
——————————-
Now I am not a big fan of Ice Core proxies, especially those extracted from the Greenland glaciers. And my reason for saying so is that I personally believe that both the “age” of the ice core layers and the calculated atmospheric CO2 ppm quantities based on the quantity of CO2 entrapped within said ice layers …. are both highly questionable to say the least.
Now in reference to “dating glacial ice cores” I submit thee following:
Post-glacial sea level rise
The last glacial maximum was like 22,000 years BP (before present). Global temperatures started rising at around 21,000 years BP and the glacial ice began to melt ….. but then global temperatures began to surge at around 19,000 BP which caused an increase in melting of the ice. And then at 15,000 BP the temperatures must have surged again and the melting really exacerbated and continued until around 8,000 years BP which resulted in the current ocean levels which are 130 meters or 450 feet higher than they were during said glacial maximum.
Reference graph – sea level proxies: http://schools-wikipedia.org/images/439/43917.png
—————–
Given the above said we have to assume that near-surface air temperatures were extremely warm and rising up until 8,000 years BP.
And just how warm were those near-surface air temperatures post-8,000 years BP?
To answer that question we have to acknowledge the finding of the following peer reviewed study, to wit:
Holocene Treeline History and Climate Change Across Northern Eurasia
Radiocarbon-dated macrofossils are used to document Holocene treeline history across northern Russia (including Siberia). Boreal forest development in this region commenced by 10,000 yr B.P. Over most of Russia, forest advanced to or near the current arctic coastline between 9000 and 7000 yr B.P. and retreated to its present position by between 4000 and 3000 yr B.P. Forest establishment and retreat was roughly synchronous across most of northern Russia.
During the period of maximum forest extension, the mean July temperatures along the northern coastline of Russia may have been 2.5° to 7.0°C warmer than modern. The development of forest and expansion of treeline likely reflects a number of complimentary environmental conditions, including heightened summer insolation, the demise of Eurasian ice sheets, reduced sea-ice cover, greater continentality with eustatically lower sea level, and extreme Arctic penetration of warm North Atlantic waters. The late Holocene retreat of Eurasian treeline coincides with declining summer insolation, cooling arctic waters, and neoglaciation.
Exerted from: http://www.sciencedirect.com/science/article/pii/S0033589499921233
——————————
Now the above study confirms those extremely warm temperatures post-8,000 years BP. It also confirms said temperatures remained extremely warm for like +-4,000 years between the stated 9,000 BP and 3,000 BP time frame …… otherwise the growth of those forests would never have “advanced to or near the current arctic coastline”.
And if those extremely warm temperatures (2.5° to 7.0°C warmer than modern) across all of northern Russia and the Arctic Ocean persisted for like +-4,000 years then surely those past accumulations of “yearly” surface layers of ice on the glaciers on Greenland were melting …. like they were going out of style.
Reference map: http://www.worldpress.org/images/maps/world_600w.jpg
So the BIG question is, …. how many “yearly” surface layers of ice “melted away” during said +-4,000 years? Are they not now claiming that the Greenland glaciers are melting and it has only been moderately warm in comparison for the past 100 years?
Samuel C Cogar says:
October 20, 2013 at 1:31 pm
Good questions. It also appears that up to a third of the GIS might have melted during the Eemian, which was even warmer & lasted longer than the Holocene. What effect this mass loss might have had at the high elevations & latitudes of the core samples, I don’t know.
However, there likely would have been less melting atop the GIS domes than near sea level farther south, as along the Siberian tree line. Whether there are whole years missing from the core record during the Holocene Climatic Optimum, I also don’t know, but suspect not.
IMO it’s clear that Earth has been in a long-term cooling trend for over 3000 years. And that there were probably thousands of summers during the Optimum in which the Arctic Ocean was effectively sea ice free.
Sorry, I meant ANDREW KHAN is Poptech, blog author of Popular Technology. Did I spell your name right this time?
Poptech, if you were so smart you would not keep repeating that your name is NOT ANDREW KHAN. You would remain silent and let others think that it is. Stay calm and think hard for once Andy.
Samuel C Cogar quotes:
“During the period of maximum forest extension, the mean July temperatures along the northern coastline of Russia may have been 2.5° to 7.0°C warmer than modern. The development of forest and expansion of treeline likely reflects a number of complimentary environmental conditions, including heightened summer insolation, the demise of Eurasian ice sheets, reduced sea-ice cover, greater continentality with eustatically lower sea level, and extreme Arctic penetration of warm North Atlantic waters.”
Reduced sea-ice cover and extreme Arctic penetration of warm North Atlantic waters takes negative Arctic and North Atlantic Oscillation conditions, the opposite of what would happen in the warmest periods.
Poptech says:
October 19, 2013 at 7:15 pm
Jimbo, my name is not Andres Khan despite your ignorance of all things Internet related. I am only electronically dangerous to people wish me to be banned.
================
Don’t want to see you banned.
You enliven the discussion.
I mean it is a discussion, within this blogs policies.
There are other blogs where you can say anything you want.
After my last “on the spur of the moment’s” comment on October 18, 2013 at 6:26 pm, I have done some internet searching as I am quite certain that there is a very good reason as to why “more snow is falling and staying longer into the summertime, on a regular enough basis to bring on an “Ice Age”, that is – and so I asked my ‘search engine’: “ Is the Earth’s axial tilt increasing or is it decreasing?
Many clever answers were returned and I could only deduce that our planet is getting to be “more upright” and that the seasons will therefore change. – O K, so it is a very slow process but it must mean that during every summer (N&S), both Poles are pointing a little bit “less directly” at the Sun and therefore both Hemispheres may gradually cool. One question of course is: “Will the more upright tilt mean correspondingly warmer winters”? – Well, I doubt it will make up for the ‘Summer Chill’, also if “The Holocene Maximum” was 1 – 1.5 ºC warmer than it is at the present, or ‘half a degree of tilt ago’, then another 1.5 degrees of pointing away from the Sun, should mean a further cooling of, say 4.5 ºC, as a minimum. Which would gradually, during the next few thousand years, bring this planet back into, an other glaciation. – Oh and if we add in a bad Solar Minimum or two, i.e. the Little Ice Age (LIA) or the Roman Cold Period (RCP), or anything else you guys can think of, it may come a lot sooner than I think.
P.S.
Under: Axial tilt – Wikipedia, the free encyclopedia I read: “The Earth’s axial tilt is decreasing, but the change is very slow. The amount is 0.47 arcseconds per year. This means that the Tropic of Cancer and the Tropic of Capricorn are both moving towards the equator at the rate of about 15 metres per year, so you can see it’s not very much. The tilt varies over the range 22.1º to 24.5º over a period of 41,000 years.
http://en.wikipedia.org/wiki/Axial_tilt
On it’s own, change of axial tilt might not cause much climate change. But combined with the variation in the eccentricity of the Earth’s orbit and precession of the Earth’s axis, there is some correlation between the periods of these cycles and past climate change. See Milankovitch Cycles: http://en.wikipedia.org/wiki/Milankovitc…
At the end of reading that entire page, I also read a postscript: “This page was last modified on 17 October 2013 at 01:43.”
So, somebody is keeping ‘an eye on it’
In any case if the Earth began to come out of one of its many “Glaciations” some 20 – 15 thousand years ago when the ‘axial tilt’ was at it’s maximum, say 24º, then it seems reasonable to me that the beginning of the Holocene, or of any other ‘long lasting warm period, would be warmer than it becomes some 10 – 15 thousand years later – and they all do (the last 5 major interglacial periods) – or have done, as far as I can see.
And, – 150.000 years from now – our descendants will look at, and compare, the by then, new Greenland- and the Antarctic Ice-Core-Graphs and say: “This can’t be right, the ancient scriptures say – – – – – -.”
Jimbo, you never answered the question… how does it feel to be my puppet? I think I am going to create a list puppets like you that I now control.
[Reply: Stop it! — mod.]
It is only funny if you don’t know how to use Google and forget to use quotes.
[Reply: Stop it! — mod.] – please see Jimbo’s posts October 20, 2013 at 3:18 pm + 3:23 pm.
[Reply: OK then, both of you, Stop It! — mod.]
Once last thing, so there is no confusion, Willis’s peer-reviewed papers are still on my list and will never be removed unless they get retracted. Any new peer-reviewed papers of his will be added in future updates.
http://www.populartechnology.net/2009/10/peer-reviewed-papers-supporting.html
E.M.Smith (The Chiefio) also thinks we may be overdue for a severe bout of cooling. See http://chiefio.wordpress.com/2012/12/29/annoying-lead-time-graph/
Spectacularly OT – but most important nonetheless (at least, that’s what it is for me…):
Thanks a million times for your good advise on efficient [breathing], Willis.
At first I was a sceptical, when I read what you were proposing the other day, umm: Thread. But then I gave it a try, just out of curiosity – and experienced a truly SPECTACULR success.
i am a big, heavy guy – I am six feet, two inches tall, and my weight exceeds 300 ponds easily – but I am not only fat. In my younger years, I did lots of competitive Judo and weight-lifting, but failed to train down properly after I had to stop my sporting activities. So yes, under the fat there’s still lots of muscles which are greedy for oxygen,whenever I start to move.
Now in my early Fifties, I was quite short on breath already, as soon as I started walking fast or, God forbid, running. But owing to you advise to EXHALE properly, instead of concentrating on breathing IN as much as I can, I have almost DOUBLED the distance I can walk/run/climb stairs until I finally run out of breath INSTANTLY.
This, in turn, means, that walking/running/climbing stairs for me finally is FUN again, and will help reduce my weight to sensible levels, now that i know how to breathe to not run out of breath the next moment, whenever I start moving.
Thanks again, Willis. Your advise helped improve my life 100 percent!
But why don’t they teach stuff like this at school…?
Ulric Lyons says:
October 20, 2013 at 3:37 pm
Reduced sea-ice cover and extreme Arctic penetration of warm North Atlantic waters takes negative Arctic and North Atlantic Oscillation conditions, the opposite of what would happen in the warmest periods.
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Ulric, I was not learned in/on what said A&NA Oscallations were …. so I had to “read up” on said ……. and what I found is contrary to what you stated above, to wit:
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Global Patterns – Arctic & North Atlantic Oscillations (AO & NAO)
The Arctic Oscillation (AO) is a climate index of the state of the atmospheric circulation over the Arctic. It consists of a positive phase, featuring below average geopotential heights , which are also referred to as negative geopotential height anomalies , and a negative phase in which the opposite is true.
In the negative phase, the polar low pressure system (also known as the polar vortex) over the Arctic is weaker, which results in weaker upper level winds (the westerlies). The result of the weaker westerlies is that cold, Arctic air is able to push farther south into the U.S., while the storm track also remains farther south.
The opposite is true when the AO is positive: the polar circulation is stronger which forces cold air and storms to remain farther north. The Arctic Oscillation often shares phase with the North Atlantic Oscillation (NAO) (discussed below), and its phases directly correlate with the phases of the NAO concerning implications on weather across the U.S
http://www.nc-climate.ncsu.edu/climate/patterns/NAO.html
In reference to what …………
O H Dahlsveen says:
October 20, 2013 at 6:51 pm
The following was exerted from: http://en.wikipedia.org/wiki/Tropic_of_Cancer
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Tropic of Cancer
The Tropic of Cancer currently (Epoch 2012) lies 23° 26′ 16″ [2] north of the Equator. Its position is not fixed, but varies in a complicated manner over time. It is presently drifting south at the rate of almost half a second (0.47″) of latitude per year (it was at exactly 23° 27′ in year 1917).
Carretera 83 (Vía Corta) Zaragoza-Victoria, Km 27+800. In all crossings of the Tropic of Cancer with Mexican federal highways, this is the only place where the latitude is marked with absolute precision and where the annual drift between 2005 and 2010 can be appreciated.
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Click link below to see photo of that “yearly drift” southward.
http://en.wikipedia.org/wiki/File:Tr%C3%B3pico_de_C%C3%A1ncer_en_M%C3%A9xico_-_Carretera_83_(V%C3%ADa_Corta)_Zaragoza-Victoria,_Km_27%2B800.jpg
@Samuel C Cogar
With negative AO/NAO conditions there are increased surface winds in the Arctic causing ice beak up and drift. And of course with a weaker vortex and incursions of Arctic air southwards, warmer air from the mid latitudes exchanges with it into the arctic. Nothing you quoted is contrary to what I said, though it is incomplete. And it is estimated that ~60% of increased sea ice loss is due “extreme Arctic penetration of warm North Atlantic waters”, that occurs consistently with negative Arctic and North Atlantic Oscillation conditions.
“So … would it not be truly ironic if pollution, in the form of soot and brown carbon, were all that has been holding off another ice age?”
http://climal.com/previous-story-1.php
mogamboguru says:
October 21, 2013 at 6:41 am
Many thanks, mogamboguru. I put it out there and said it wouldn’t help some people, but others might just get the amazing benefits I got from it … and I’ve taken some stick out there on the intarwebs for doing so, people claiming I was out of line, or that I was doing it for some egotistical reason.
But I did it for a simple reason—I’d gotten huge benefit from it, and I thought others might as well.
So thank you kindly for letting me know that it has worked for you. I don’t know of anything I have to give away that’s more valuable than that, I’m stoked that you’ve gotten so much out of it.
Regards,
w.
Willis Eschenbach says: October 19, 2013 at 10:02 pm
I do not know why Poptech has taken such bitterness and enmity upon himself towards me. I’m sorry to see it, and if it is for some slight or humiliation that I’ve put upon him, he has my apologies…………………………….So I’m not opposed to Poptech agitating to correct what he sees as mis-statements. I don’t see them as that, but I’m not concerned about his doing it, I don’t see it as a problem. A google search on “willis eschenbach” brings up a quarter million pages, so it is going to be a long task.
__________________
I’m a nobody on this blog but I read here every day and occasionally post. I very much appreciate Willis and the WUWT community.
I’m not sure what the reasonings are for not banning Poptech. My inclination is to trust the judgment of WUWT…..frankly I wonder if Poptech’s threats have something to do with this. I bet I’m not alone in wondering if WUWT is intimidated by Poptech’s threats.
I freely assert that Poptech has a horrible, reprehensible reputation on the web. He’s revealed himself here to be a threatening stalker. His rep is worse……… EVERYWHERE. Google him and you will very quickly learn who and what he is as if his antics and threats here have not already convinced you. IMO he’s bad for skeptics and really no better than slayers or Dr. Mann. It’s past time to police our own and shun Poptech. Poptech has been banned and shunned all over the web…..It’s time to kick him to the curb here IMO unless or until he apologizes to Willis and the WUWT community.
[trimmed. Mod]
@ Ulric Lyons
You sure confused me with this statement of …. “there are increased surface winds in the Arctic ……[snip]…… and incursions of Arctic air southwards, warmer air from the mid latitudes exchanges with it into the arctic.”
That sounds like you got the surface air going both directions at the same time.
Ulric, all I can say is, …. click this link and read the abstract yourself, to wit:
http://www.sciencedirect.com/science/article/pii/S0033589499921233
Samuel C Cogar says:
“That sounds like you got the surface air going both directions at the same time.”
Precisely, exchange of Arctic and Temperate air occurs with weak polar vortex conditions.
OK, thanks to the explanation at this link, to wit:
http://www.aer.com/science-research/climate-weather/climate-dynamics/polar-vortex-impact-winter-weather
I now understand what you are saying.
And I think it also explains an event that bedazzled me when it occurred some 40 years ago.
At the time I was living in upstate NY on top of a hill overlooking the City of Utica. I had a wood burning cook stove in the kitchen, against the wall, on the North end on the house which was used for both cooking and keeping that end of the house warm. In the winter time I would wake up at 1 or 2 am and stoke the fire up to keep it going.
One morning when it was like -10 F degrees outside I was doing my chore and just when that added firewood started burning good ….. “WHOOOOOSH”, ….. smoke started pouring out of every crack, crevice and opening in that stove and quickly filled up the kitchen area. I shut the air input and flue pipe dampers off but that that didn’t help much. Anyway, I was forced to open the door to the outside to get rid of the smoke knowing full well that at -10 F and a fairly strong wind blowing that it would “kick” my oil-fired furnace into high-gear to warm the house back up.
But, “WOW”, when I stepped outside to get a breath of fresh air is was like 45 F degrees and that strong wind was coming directly out of the South and across the top of my house. Now that explained the “down pressure” causing my stove to smoke like a heavy hauling coal fired RR locomotive going upgrade ……. but I never ever bothered to figure out what caused that Warm Front to push directly North.
Now I think I know.
Cheers, Sam C