Reader “Markx” writes in Tips and Notes on a paper I hadn’t noticed before (because it was published before WUWT was born). Of course it only works if CO2 has a long residence time and/or our elevated emission levels continue. We need at least 3x more CO2 to pull off the delay.
A movable trigger: Fossil fuel CO2 and the onset of the next glaciation. David Archer and Andrey Ganopolski
Published in G3 Geochemistry Geophysics Geosystems Research Letter Volume 6, Number5 5 May 2005
Abstract:
The initiation of northern hemisphere ice sheets in the last 800 kyr appears to be closely controlled by minima in summer insolation forcing at 65N. Beginning from an initial typical interglacial pCO2 of 280 ppm, the CLIMBER-2 model initiates an ice sheet in the Northern Hemisphere when insolation drops 0.7 s (standard deviation) or 15 W/m2 below the mean. This same value is required to explain the history of climate using an orbitally driven conceptual model based on insolation and ice volume thresholds (Paillard, 1998). When the initial baseline pCO2 is raised in CLIMBER-2, a deeper minimum in summertime insolation is required to nucleate an ice sheet. Carbon cycle models indicate that 25% of CO2 from fossil fuel combustion will remain in the atmosphere for thousands of years, and 7% will remain beyond one hundred thousand years (Archer, 2005). We predict that a carbon release from fossil fuels or methane hydrate deposits of 5000 Gton C could prevent glaciation for the next 500,000 years, until after not one but two 400 kyr cycle eccentricity minima. The duration and intensity of the projected interglacial period are longer than have been seen in the last 2.6 million years.
Some excerpts:
“Models require some amplifying feedback, from sea ice … or the terrestrial biosphere ….to nucleate on the basis of insolation forcing, but insolation is always the primary driver.”
and
An anthropogenic release of 300 Gton C (as we have already done) has a relatively small impact on future climate evolution, postponing the next glacial termination 140 kyr from now by one precession cycle.
Release of 1000 Gton C … is enough to decisively prevent glaciation in the next few thousand years, and given the long atmospheric lifetime of CO2, to prevent glaciation until 130 kyr from now.
If the anthropogenic carbon release is 5000 Gton or more….[…]… The model predicts the end of the glacial cycles, with stability of the interglacial for at least the next half million years…
Figure 3. Effect of fossil fuel CO2 on the future evolution of climate. Green represents natural evolution, blue represents the results of anthropogenic release of 300 Gton C, orange is 1000 Gton C, and red is 5000 Gton C. (a) Past and future pCO2 of the atmosphere. Past history is from the Vostok ice core [Petit et al., 1999], and future anthropogenic perturbations are from a carbon cycle model [Archer, 2005]. (b) June insolation at 65N latitude, normalized and expressed in s units. 1 s equals about 20 W m2. Green, blue, orange, and red lines are values of the critical insolation i0 that triggers glacial inception. The i0 values are capped at 3 s to avoid extrapolating beyond model results in Figure 3; in practice, this affects only the 5000 Gton C scenario for about 15 kyr. (c) Interglacial periods of the model. (d) Global mean temperature estimates.
Not having mile thick ice sheets crush northern hemisphere cities is a good thing, don’t you think?
Full PDF here: http://geosci.uchicago.edu/~archer/reprints/archer.2005.trigger.pdf
I have just taken my Playtex 24hr girdle off, if I start laughing now…well it will just get ugly!
Wow! To think that me and my BBQ are holding back the miles of ice that should be crushing New York and with it Jim Hansen’s office under miles of grinding ice.
I am awesome!
ferdberple says (April 27, 2013 at 7:35 am): “Otherwise, we are left with the 1950′s alternative. Building thousands of nuclear power plants to heat the oceans, and/or thousands of gigantic solar reflectors in space to warm the land.”
Or dusting the ice & snow with black carbon…
“…pCO2 of 280 ppm…” What is “p” CO2?
pCO2 is the negatve log (10) of the CO2 concentration in water in moles per liter
ppm ((=mg per kg) is not the right dimension for this
Just as I thought!
According to Berger and Loutre 2002, the next Ice age is not due until 50.000 years from now.
An Exceptionally Long Interglacial Ahead?
A. Berger and M. F. Loutre
Today’s comparatively warm climate has been the exception more than the rule during the last 500,000 years or more. If recent warm periods (or interglacials) are a guide, then we may soon slip into another glacial period. But Berger and Loutre argue in their Perspective that with or without human perturbations, the current warm climate may last another 50,000 years. The reason is a minimum in the eccentricity of Earth’s orbit around the Sun.
Science 23 August 2002:
Vol. 297. no. 5585, pp. 1287 – 1288
DOI: 10.1126/science.1076120
ftp://ftp.soest.hawaii.edu/engels/Stanley/Textbook_update/Science_297/Berger-02.pdf
Earth: 26% clouds, 0.65 cloud albedo, 341.5 W/m2 TOA TSI: 57.7 W/m2 reflection. 15 W/m2 increase in cloud reflection , is 32.8% cloud cover Earth.
What would that take?
A strange rehash of Berger and Loutre(2003). “An Exceptionally Long Interglacial Ahead”- Science. Also, the resolution in Fig 3 does not show the proper decline in June insolation at 65N
over the next few thousands of years.
C’mon folks, this is a trap. Our dear David Archer is a true believer in CAGW. It only takes a couple moments to google this ‘clever’ professor’s name. He’s such a twit he actually believes that we’re at a tipping point of, sinister drum beat please, no return. Our weekend frolic with industrialization turned into a weekend of sheer, pee in the pants, terror. You know the rest. In fact, our bearded (in which case I’ve got them all beat) professor seems to occupy a place at Real Climate. Now, I don’t wish to get down on the University of Chicago (since most of the virtual army of doctors I see practice there) but our current frowning POTUS, Mr. Barack Obama was one of the visiting, wink, wink, scholars there and Mr. Archer still comfortably resides there. Make no mistake, he’s quite familiar with the ‘Chicago Way.’ If anybody believes his paper, and he’s hoping skeptics will, he’ll do a switharoo.
Ray
“Not having mile thick ice sheets crush northern hemisphere cities is a good thing, don’t you think?”
Think of all the shoveling we would save…
We could do some strategic shovelling in order to improve the lives of hundreds of millions. Give Washington (DC) and Brussels a miss perhaps?
From NASA Earth Fact Sheet Mass of atmosphere ~ 5.1 * 10^18 kg
The EIA shows CO2 emissions from energy use from 1980 through 2011 as 753,896.0782 million metric tons.
The Mona Loa CO2 measurements are
2011 391.62 ppm
1980 338.68 ppm
This is a change of 52.94 ppm
Using the 5.1 * 10^18 kg for atmosphere we get an increase of 2.7 * 10^14 kg of CO2.
This is 270,000 million metric tons, but we emitted 753,896 million metric tons.
That leaves 483,896 million metric tons or about 64% that must have gone somewhere.
The models call for
“The equilibrium partitioning of a slug of new CO2
between the atmosphere and the CaCO3-buffered
oceans is such that, in the absence of natural CO2
forcing such as glacial inception, approximately
7% of the CO2 remains in the atmosphere 100 kyr
after the perturbation,…”.
If the process is linear, this would be a time constant of about 37,000 years, so in the 31 years,
assuming that it had all been dumped in in 1980, we should have had about 621 million metric tons taken up in the by the modeled process. This leaves about 483,275 million metric tons which went somewhere.
It would take some very persuasive arguments in a fairly concise form before I would consider it worthwhile to look closely at their models for the lifetime of atmospheric CO2.
Donald Mitchell
Henry@donald
I know where the missing 60% went
namely
everyone wants more trees, more lawns
they also want more wine, more crops,
and then God decided to give it to them
and He makes it from water and CO2……
mostly..
God bless you all here!
“If Humanity can Geo-engineer so readily, Why not turn Mars into Hawaii.
The hubris, it burns.”
For all those people rabbiting on about how close we are to terraforming other worlds, I ask why not turn the rest of Earth into Hawaii? Forget Mars! I say, “Earth First!”
It’s doubtful that CO2 has enough influence to stop an ice age but the ready availability of fossil fuels and nuclear power may well help the human race survive it.
Just 2 points:
1) Did you forget water vapour? The most powerful greenhouse gas.
2) “It stands to reason that the “right” amount of CO2, at the right time, could keep us out of another ice age….”
Oh really! Click here and look at the later half of the Cretaceous and start of the Tertiary.
It would be wonderful if it were true, but,
RGB@Duke eloquently reminded us some time ago, that we entered a glaciation during the Ordovician period when co2 was at 7000 ppm and that glaciation continued through much of the Silurian period when co2 never dropped below 4000 ppm.
Clearly co2 plays no part in preventing glaciations. The authors haven’t done their homework.
I reckon Jasper Kirkby and or Svensmark might well have a good idea about the answer. Perhaps an examination of Livingston & Penn (& recently Svalgaard) might also lead to some conclusions.
And even IF
(just for the sake of argument) CO2 could prevent glaciations, the amount of CO2 emitted by NON-human sources would still be FAR AND AWAY the controlling causation of any (just for the sake of argument) warming.
[Just a non-scientist wanting to reinforce the politically (and given that people are dying due to fantasy science policies), VITALLY) essential fact that HUMANS CAN DO NOTHING ABOUT the EFFECTIVE level of CO2 in the atmosphere.]
William Astley says:
April 27, 2013 at 8:32 am
“There are burn marks on the surface of the planet that correlate with Younger Dryas abrupt cooling period (the duration of the Younger Dryas cooling event is roughly 1000 years). There are burn marks on the planet’s surface that correlate with other geomagnetic excursions.”
This bit is tucked in between “a restart of the solar magnetic cycle after it has been interrupted” and “massive discharge from the sun”, such that one might get the idea that something has been scorched by the Sun. Either that or there has been something left out while doing a hurried cut and paste construction.
The Carolina Bays . . .
http://en.wikipedia.org/wiki/Carolina_Bay
. . . have been cited as “burn marks” although these seem explainable by known terrestrial processes. So, if such as these are what you mean by “burn marks”, perhaps you can explain what did cause them. If you have some other set of features in mind – what are they?
We are still at the mercy of the sun, super volcanoes, meteors, cosmic radiation from super novas and some event we do not know of yet.
William Astley says:
April 27, 2013 at 8:32 am
===================================
Bravo!
Milankovitch holds but one seat on the glacial/interglacial board of directors and Carbon dioxide is a minor stockholder.
As we congratulate ourselves with our 75% correlation understanding of the twitters of glacial/interglacial oscillations, we must remember that behind this looms the task of explaining why the last session of tweets ended in the early Permian about 250 million years ago, and the entire interval from then to the Pleistocene, including many orbital cycles, and including the “nuclear winter” of the Club Med impact, was much warmer than today with no ice sheets to recede or advance.
It’s clear we have to act immediately. We must make that movie about modern climate science while Jerry Lewis is still alive.
If I remember well, according to models based on radiative forcing, the cooling after Younger dryas did not happen. It is present in the ice core record, but according to the models it did not happen, since radiative forcing in computer model says it could not happen.
Canman says:
April 27, 2013 at 7:18 am
In his book, “Coal Trains of Death” Hansen says that the output from a single chlorofluorocarbon plant is enough to prevent an ice age.
Would that be before or after the oceans boil?
🙂