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What caused global temperatures to fall in the past?
Posted: 27 July 2017 10:35 AM   [ Ignore ]   [ # 16 ]
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JohnH - 26 July 2017 11:49 AM

Yes Mike, but efforts to reliably relate climate change to Milankovitch cycles haven’t been particularly successful.

 
Good question. The answer is that we need the computer models to accomplish the task. Before the models can work we need to establish reliable data. That is where we are at now, building the system to collect reliable data. Just this week the news is that the energy coming from the sun to the earth was wrong. And new figures are now available for use. Basically, all past reports using the sun’s energy is now considered wrong. The point being, like CC stated that weather is the combination of earth’s reaction to the energy from the sun. That energy is constantly changing with the Milankovitch cycles, the sun’s eleven-year solar cycles and solar flares.   
 

How are they linked to fluctuations in atmospheric carbon dioxide?


The Ice Cores show that the Milankovitch cycles warms and cools the earth. The carbon dioxide follows the warm and cool cycles of the Global Warming. But, the Climate Change has broken the standard Global Warming cycle. We are in new territory with Climate Change caused by huge amounts of anthropogenic gases.
//www.ipcc.ch/publications_and_data/ar4/wg1/en/faq-6-1.html
My choice is to choose factual science over consensual science. The problem is factual science takes time. Consensual science is what we have today. I have been backing the direction of the IPCC. The problem is that the IPCC is getting a lot more political pressures than it should. 
 
 

The worrisome issue to me isn’t the accuracy of the simulated carbon dioxide effect but the recognition that past climate cycles resulted in global mean temperatures higher than current temperatures. That means maximum temperatures were even higher, though I haven’t encountered estimates for maximum temperatures. Essentially, that means current concerns are over potential global temperatures that have been found to occur in the natural climate changes of the past. That history suggests that our efforts to “normalize” atmospheric carbon dioxide levels may not hold global temperatures below that which is currently considered to be problematic. That isn’t to deny that current levels of anthropogenic greenhouse gas emissions may add an additional, perilous variable to climate dynamics and that it should be reversed but I worry that the challenge will turn out to be more complex than just greenhouse gases alone.

 
You’re not alone. I got the same worries.

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Posted: 27 July 2017 10:24 PM   [ Ignore ]   [ # 17 ]
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CC, the reason I ignore you is that you approach debate in a hostile, obnoxious manner, responding more to your perceptions of disagreement rather than issues raised, presumably triggered by prejudices you cannot control. As a consequence, you have disrupted rather than contributed to substantive debate. Your debating style is contrary to forum rules (for example, personal attacks, suggesting I’ve joined the fools bandwagon or describing my comments as “bullshit” without any convincing explanation why. Even starting new threads in an effort to bait me.). So, yes, I choose for the most part to ignore you.
For anyone with a more level-headed interest here is an image relating several climate variables.dn11640-1_800.jpg
You may note that insolation is not well correlated with other changes. As far as I understand, attempts to incorporate Milankovitch cycles into climate simulations (climate models) have not provided a good fit with real data. If I am mistaken, references to reports of the success of such simulations will be much more convincing than simply characterizing my comments (possibly based on ignorance) as “bullshit” without any real evidence to back up the accusation. That is a violation of forum rules.
You may note that recent temperatures (the red line at the left side of the graph) have fluctuated within a 2 degree range for the last 10,000 years. About 20,000 years ago temperatures were 8 degrees cooler than those recent temperatures. The Little Ice Age occurred a few hundred years ago and isn’t even noticeable in the recent temperature fluctuations, so no, my focus isn’t the little ice age.
At least one of the temperature spikes at 125,000 240,000 and 320,000 years ago is higher that the IPCC projection for 2050. Other graphs show it more clearly, for example the Wikipedia paleoclimate entry. This is the source of my concern that natural climate changes may have the apparently unrecognized potential to add even more to our global warming problem. This isn’t denying or minimizing anthropogenic warming - it is a concern that we could be facing a double-whammy that we don’t seem to be prepared for.
You may also note the similarities between carbon dioxide and temperature changes in the last 4 temperature cycles. This means that carbon dioxide levels fell (naturally?) In previous climate cycles. The simple question in the OP to this thread was if anyone can point to what triggered this reversal. A further question may be what sources existing to support any explanations. By that I mean hard evidence along the lines of GCMs, not arm-waving generalities or opinion pieces by, for example a cognitive science graduate in a Department of Communication as is John Cook who runs the skeptical science website.
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Posted: 27 July 2017 11:45 PM   [ Ignore ]   [ # 18 ]
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JohnH - 27 July 2017 10:24 PM

CC, the reason I ignore you is that you approach debate in a hostile, obnoxious manner, responding more to your perceptions of disagreement rather than issues raised, presumably triggered by prejudices you cannot control. As a consequence, you have disrupted rather than contributed to substantive debate. Your debating style is contrary to forum rules (for example, personal attacks, suggesting I’ve joined the fools bandwagon or describing my comments as “bullshit” without any convincing explanation why. Even starting new threads in an effort to bait me.). So, yes, I choose for the most part to ignore you.
For anyone with a more level-headed interest here is an image relating several climate variables.dn11640-1_800.jpg
You may note that insolation is not well correlated with other changes. As far as I understand, attempts to incorporate Milankovitch cycles into climate simulations (climate models) have not provided a good fit with real data. If I am mistaken, references to reports of the success of such simulations will be much more convincing than simply characterizing my comments (possibly based on ignorance) as “bullshit” without any real evidence to back up the accusation. That is a violation of forum rules.
You may note that recent temperatures (the red line at the left side of the graph) have fluctuated within a 2 degree range for the last 10,000 years. About 20,000 years ago temperatures were 8 degrees cooler than those recent temperatures. The Little Ice Age occurred a few hundred years ago and isn’t even noticeable in the recent temperature fluctuations, so no, my focus isn’t the little ice age.
At least one of the temperature spikes at 125,000 240,000 and 320,000 years ago is higher that the IPCC projection for 2050. Other graphs show it more clearly, for example the Wikipedia paleoclimate entry. This is the source of my concern that natural climate changes may have the apparently unrecognized potential to add even more to our global warming problem. This isn’t denying or minimizing anthropogenic warming - it is a concern that we could be facing a double-whammy that we don’t seem to be prepared for.
You may also note the similarities between carbon dioxide and temperature changes in the last 4 temperature cycles. This means that carbon dioxide levels fell (naturally?) In previous climate cycles. The simple question in the OP to this thread was if anyone can point to what triggered this reversal. A further question may be what sources existing to support any explanations. By that I mean hard evidence along the lines of GCMs, not arm-waving generalities or opinion pieces by, for example a cognitive science graduate in a Department of Communication as is John Cook who runs the skeptical science website.
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what response did you get when you when you posted your question on global warming scientific forums such as skeptical science because we can see how concerned on getting an educated answer.

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Posted: 28 July 2017 06:59 AM   [ Ignore ]   [ # 19 ]
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JohnH, I don’t expect you to get an answer that is agreed upon by the consensual scientists. This question has been around for some time and there have been warnings from several scientists about how the lags and jumps work. But, no reaction or responses from the Global Warming movement. I have read that even Al Gore has taken the famous carbon following the heat details out if his charts he is using now. Point being, that if Al Gore can’t give an answer, then he doesn’t have the answer or the answer does not agree with his claims on how the CO2 works. A question that has not been answered is does the CO2 blanket only heat to a given point, no matter how much CO2 is in the air. During snowball earth, the C02 levels were said to be 300 times greater than today’s levels. Therefore, the computer models are the key to solving the questions of how and what we must do to make sure we save mankind.

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Posted: 28 July 2017 09:29 AM   [ Ignore ]   [ # 20 ]
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JohnH - 27 July 2017 10:24 PM

CC, the reason I ignore you is that you approach debate in a hostile, obnoxious manner, responding more to your perceptions of disagreement rather than issues raised, presumably triggered by prejudices you cannot control. As a consequence, you have disrupted rather than contributed to substantive debate. Your debating style is contrary to forum rules (for example, personal attacks, suggesting I’ve joined the fools bandwagon or describing my comments as “bullshit” without any convincing explanation why. Even starting new threads in an effort to bait me.).

Oh but you believe you have the right to slander and libel scientists and their science???
Then not support your slander and we are supposed to accept that???

JohnH - 27 July 2017 10:24 PM

describing my comments as “bullshit” without any convincing explanation why.

Really, really  blank stare  can you explain why this is unconvincing?

Also see
Archive, Hanscom AFB Atmospheric Studies,
Cambridge Research Lab

http://whatsupwiththatwatts.blogspot.com/2016/02/archive-usaf-atmospheric-studies-afcrl.html
~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~

The increase in atmospheric concentration of CO2 since preindustrial times is a given. Understand that the radiative physics of greenhouse gases are very well-understood.

Consider heat seeking missiles flying through different altitudes searching for a heat source who’s signature is changing with altitude.  In order to program the computer, the programmer must know how to accurately compensate for the changing signature.  It requires a complete knowledge of the radiative properties of all the gases in the atmosphere, or all that hardware is for naught.

{Incidentally, there is not one contrarian “theory” or challenge to the physics that hasn’t been looked at by informed individuals.  You’ll find that contrarian errors, omissions, and falsifications have been clearly explained.  Don’t believe me, check it out for yourself:
http://www.skepticalscience.com/argument.php?f=taxonomy
Continue for the list of CO2 dependent modern marvels:
~ ~ ~ ~ ~ ~ ~
* Weather satellites that can image heat and moisture and wind’s effects into comprehensible images.
~ ~ ~ ~ ~ ~ ~
* Precipitable water. Contrast brightness temperatures measured via oxygen emissions and via H2O emissions to back calculate how much water is present.
~ ~ ~ ~ ~ ~ ~
* Heat seeking air to air missiles, they would not function if those guidence computers didn’t have a complete description of how heat moves through the atmosphere.
~ ~ ~ ~ ~ ~ ~
*  Lasers wouldn’t work if we had radiative physics wrong.
~ ~ ~ ~ ~ ~ ~
* Early-Warning satellites.  How are they going to distinguish between a missile launch from lightning, over Siberia?  Better look at IR in DETAIL!  (There’s much more)

Spectroscopic Databases such as HiTran and Geisa have military origins. Going back to WWII and the desire to do Night Bombing better. Then this continued during research programs in the 50’s & 60’s, with a lot of it through the Cambridge Research Laboratory.

The program ModTran that is an example of a narrow band Radiative Transfer Code, for calculating radiative transfer. Half the patents for this are held by the Pentagon. The company that develops it - Spectral Sciences Inc - does so under license to the United States Air Force.
http://modtran5.com/
http://www.spectral.com/MODTRAN.shtml
http://climatemodels.uchicago.edu/modtran/

For 20 years developments to ModTran were signed off by the Commandant of the USAF GeoPhysics Laboratory, Hanscom AFB, Ma. These days it is the responsibility of the Commandant, the USAF Laboratory, Kirtland AFB, NM.
~ ~ ~ ~ ~ ~ ~

*  The detection of specific chemicals in the atmospheres of exoplanets:
By modeling the gases at high pressures, you can produce an expected absorption for infrared from the planet and compare the model to the spectra recorded by the Spitzer space telescope.
~ ~ ~ ~ ~ ~ ~

*Spectroscopy includes measurement of absorption of IR wavelengths
eg measurement of CO2 levels in the atmosphere and ice cores relies on IR absorption. (that would make using ice core records to “prove” GHE doesn’t exists amusing)
“Each sample has a volume of 4~6 cm3. CO2 concentration was measured with IR tunable diode laser spectroscopy, scanning a single vibrational-rotational absorption line.”  https://nsidc.org/data/docs/agdc/nsidc0202_wahlen/
~ ~ ~ ~ ~ ~ ~

*  And it’s not just physics of the standard GH gases.
Microwave emissions of oxygen molecules gives us satellite temperature sensing of the atmosphere.
Nitrogen - Nitrogen collisions form part of the basis of the GH effect on places like Saturn’s moon Titan.
~ ~ ~ ~ ~ ~ ~

*  Getting out of the IR range, but the Dobson spectrophotometer designed in 1924 to measure ozone (and the standard instrument for doing so, for many years) is based on the application of Beers Law. Using two close wavelengths that differ mainly in their O3 absorption coefficients, total column O3 is determined by the difference in transmission (sun view).
Careful selection of wavelengths allows measurement of many atmospheric gases.
IR instruments for CO2 and H2O are off-the-shelf items.
~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~

But wait, there’s more . . .
Check out this power point for a complete review of what scientists understand, it’s first class - perhaps the best summation for nonscientists I’ve seen:

Greenhouse Gas and Climate Science Measurements
The SIM Metrology School October 28 – November 1, 2013

James Whetstone
Special Assistant to the Director for Greenhouse Gas Measurements
National Institute of Standards and Technology, USA
http://www.nist.gov/iaao/upload/SIM_School_Climate_Final_James_Whetstone.pdf

Outline
• The Sun and The Earth–Protection Mechanisms for Life on the Surface
• Properties of Earth’s Atmosphere–Earth’s energy budget and greenhouse mechanisms – Greenhouses
~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~

Atmospheric Propagation and Effect
The Atmospheric Propagation and Effect department focuses on laser applications in the open atmosphere. Main topics are the use of laser radiation over long distances, such as optical energy transmission (laser power beaming, laser-based air defence) and the remote detection of pollutants and hazardous substances.

Home:  Institute:Departments:Atmospheric Propagation and Effect
http://www.dlr.de/tp/en/desktopdefault.aspx/tabid-2789/
~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~

“CHRONOLOGY From the Cambridge Field Stations to the Air Force Geophysics Laboratory 1945-1985”.
Liebowitz, Ruth P.  |  Hanscom Air Force Base Geophysics Laboratory.
Bedford, Massachusetts

(For highlights link to http://whatsupwiththatwatts.blogspot.com/2016/02/archive-usaf-atmospheric-studies-afcrl.html)
~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~

The Rise and Fall of Air Force Cambridge Research Laboratories.
Edward E. Altshuler |  January 2, 2013.
http://www.amazon.com/Rise-Force-Cambridge-Research-Laboratories/dp/1481832514
~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~

https://en.wikipedia.org/wiki/Infrared_homing
~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~

History of Australian research into Airborne Laser weapons systems
HIGH ENERGY LASER WEAPONS
Australian Aviation & Defense Review
by Carlo Kopp, December, 1981
http://www.ausairpower.net/AADR-HEL-Dec-81.html
~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
http://whatsupwiththatwatts.blogspot.com/2016/12/co2-science-just-facts.html

And yes you damned well bet I am livid with the decades of easy acceptance of slander and lies and the deliberate misrepresentation of what the serious science is telling us.

Okay time to get to the rest of what promises to be your most interesting post.

Edit - S.N., finally let me back in to do a couple fixes

[ Edited: 30 July 2017 09:31 AM by Citizenschallenge-v.3 ]
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Posted: 28 July 2017 10:48 AM   [ Ignore ]   [ # 21 ]
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JohnH - 27 July 2017 10:24 PM

As far as I understand, attempts to incorporate Milankovitch cycles into climate simulations (climate models) have not provided a good fit with real data. If I am mistaken, references to reports of the success of such simulations will be much more convincing than simply characterizing my comments (possibly based on ignorance) as “bullshit” without any real evidence to back up the accusation.

But wait a minute - you (and others) haven’t presented any references to support your claim to begin with!
Cough it up.

Also one reason I come off as so hostile is because all it takes is a quick google search, I typed in
“incorporate Milankovitch cycles into climate simulations”

Glacial Cycles and Milankovitch Forcing - Minnesota Journal of ...
https://mjum.math.umn.edu/index.php/mjum/article/download/13/22/

We incorporate Milankovitch cycles into a recent conceptual climate model of ... The resulting simulations exhibited glacial cycles and also exhibited the skipped ...
Milankovitch Cycles — OSS Foundation
ossfoundation.us › Projects & Resources › Environment › Global Warming

Our current climate forcing shows we are outside of that natural cycle forcing range. ... Oeschger Events · Earth’s Radiation Budget · Empirical: Modeling v. ... The Milankovich cycles are caused by changes in the shape of the Earth’s orbit around ... factors can help push the climate system into ice ages, when the this cycle is ...

Milankovitch Cycles and Glaciation
http://www.indiana.edu/~geol105/images/gaia_chapter_4/milankovitch.htm
It is of primary importance to explain that climate change, and subsequent periods of ... The first of the three Milankovitch Cycles is the Earth’s eccentricity.
Missing: incorporate ‎simulations

Milankovitch Tutorial - sciencecourseware.org
http://www.sciencecourseware.org/eec/GlobalWarming/Tutorials/Milankovitch/

These Milankovitch Cycles. are named ... Milankovitch, who used them to explain the advance ... believe these cycles play a role in the Earth’s climate. In this ...
Temperature response of Mars to Milankovitch cycles - Schorghofer ...
onlinelibrary.wiley.com/doi/10.1029/2008GL034954/full
by N Schorghofer - ‎2008 - ‎Cited by 18 - ‎Related articles

Sep 23, 2008 - [3] The orbital elements of Mars are known to about 20 Ma into the ... almost quasi-periodic manner analogous to the Milankovitch cycles of Earth ... forms a seasonal CO2 cover; this is also incorporated in the model. .... Lebofsky, L. A., and J. R. Spencer (1990), Radiometry and thermal modeling of asteroids ...
Chapter 12 Cyclostratigraphy and Milankovitch Cycles - ScienceDirect
http://www.sciencedirect.com/science/article/pii/S0070457108704278

197 Chapter 12 CYCLOSTRATIGRAPW AND MILANKOVITCH CYCLES But to ..... MILANKOVITCH THEORY orbital control, from estuarine into anti-estuarine circulation. ... The climatic simulations show that the change between the two states is ... of sedimentation to climate and because they can integrate climatic variables ...
[PPT]Simulating Milankovitch Cycles
antipasto.union.edu/engineering/Archives/.../2005/CS…/Fox_Derek_Presentation.ppt

Milankovitch Cycles – How Does it Affect Climate? ... Implement Milankovitch mathematics to visually simulate how solar insolation varies as the three cycles change ... Easier to color by breaking the polygon into smaller, 4-sided polygons. ... I accomplished what I set out to do and incorporated the features requested.
Generalized Milankovitch Cycles and Longterm Climatic Habitability
https://arxiv.org/pdf/1002.4877
by DS Spiegel - ‎2010 - ‎Cited by 66 - ‎Related articles

Jun 7, 2010 - snow and ice, susceptibility to falling into snowball states might be a generic feature of water-rich planets with the ... Earth’s eccentricity Milankovitch cycle ( though the ef- fects of the other ..... are possible. The climate simulations described in D10, .... tems, we integrate the orbit-averaged rates of change.

Milankovitch cycles include all of the following, except: .... increased temperatures can only be simulated by models when increased atmosphere CO2 ... assemble global instrumental surface temperature data into models showing global ..... Which of these was a new element incorporated into the models used for the 2007 ...

etc.

Google Scholar search would probably provide overwhelming papers on the topic, all of which the ‘skeptics’ chose to ignore.

The few I looked at quickly sure don’t support your assertion - how about you taking a look and see if you can find something that supports for your assertion.  Then lets look at what the scientists have to say about it.

So how about it can you offer any evidence to support your claim?  cheese

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Posted: 28 July 2017 11:27 AM   [ Ignore ]   [ # 22 ]
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Oh incidentally John, any reason why you didn’t share the source of your graph?
Do you have some citation to support your warmer than today claim or are we suppose to take your word for it?
rather than vaguely tossing a link to the ten year old IPCC why not cite what you think we should look at, it is a mighty long report?

Incidentally,

http://www.ipcc.ch/pdf/assessment-report/ar5/wg1/WG1AR5_Chapter05_FINAL.pdf (2013)

5.3.2 Glacial–Interglacial Dynamics
5.3.2.1 Role of Carbon Dioxide in Glacial Cycles
Recent modelling work provides strong support for the important role of variations in the Earth’s orbital parameters in generating long-term climate variability. In particular, new simulations with GCMs (Carlson et al., 2012; Herrington and Poulsen, 2012) support the fundamental premise of the Milankovitch theory that a reduction in NH summer insolation generates suf cient cooling to initiate ice sheet growth. Climate–ice sheet models with varying degrees of complexity and forced by variations in orbital parameters and reconstructed atmospheric CO2 concentrations simulate ice volume variations and other climate characteristics during the last and several previous glacial cycles consistent with paleoclimate records (Abe-Ouchi et al., 2007; Bonelli et al., 2009; Ganopolski et al., 2010) (see Figure 5.3).

There is high confidence that orbital forcing is the primary external driver of glacial cycles (Kawamura et al,. 2007; Cheng et al., 2009; Lisiecki, 2010; Huybers, 2011).

However, atmospheric CO2 content plays an important internal feedback role. Orbital-scale variability in CO2 concentrations over the last several hundred thousand years covaries (Figure 5.3) with variability in proxy records including recon- structions of global ice volume (Lisiecki and Raymo, 2005), climatic conditions in central Asia (Prokopenko et al., 2006), tropical (Herbert et al., 2010) and Southern Ocean SST (Pahnke et al., 2003; Lang and Wolff, 2011), Antarctic temperature (Parrenin et al., 2013), deep-ocean temperature (Elder eld et al., 2010), biogeochemical conditions in the North Paci c (Jaccard et al., 2010) and deep-ocean ventilation (Lisieckiet al., 2008). Such close linkages between CO2 concentration and climate variability are consistent with modelling results suggesting with high confidence that glacial–interglacial variations of CO2 and other GHGs explain a considerable fraction of glacial–interglacial climate variability in regions not directly affected by the NH continental ice sheets (Timmermann et al., 2009; Shakun et al., 2012).

[ Edited: 28 July 2017 11:45 AM by Citizenschallenge-v.3 ]
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Posted: 28 July 2017 04:34 PM   [ Ignore ]   [ # 23 ]
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Citizenschallenge-v.3 - 28 July 2017 11:27 AM

Oh incidentally John, any reason why you didn’t share the source of your graph?
Do you have some citation to support your warmer than today claim or are we suppose to take your word for it?
rather than vaguely tossing a link to the ten year old IPCC why not cite what you think we should look at, it is a mighty long report?

Incidentally,

http://www.ipcc.ch/pdf/assessment-report/ar5/wg1/WG1AR5_Chapter05_FINAL.pdf (2013)

5.3.2 Glacial–Interglacial Dynamics
5.3.2.1 Role of Carbon Dioxide in Glacial Cycles
Recent modelling work provides strong support for the important role of variations in the Earth’s orbital parameters in generating long-term climate variability. In particular, new simulations with GCMs (Carlson et al., 2012; Herrington and Poulsen, 2012) support the fundamental premise of the Milankovitch theory that a reduction in NH summer insolation generates suf cient cooling to initiate ice sheet growth. Climate–ice sheet models with varying degrees of complexity and forced by variations in orbital parameters and reconstructed atmospheric CO2 concentrations simulate ice volume variations and other climate characteristics during the last and several previous glacial cycles consistent with paleoclimate records (Abe-Ouchi et al., 2007; Bonelli et al., 2009; Ganopolski et al., 2010) (see Figure 5.3).

There is high confidence that orbital forcing is the primary external driver of glacial cycles (Kawamura et al,. 2007; Cheng et al., 2009; Lisiecki, 2010; Huybers, 2011).

However, atmospheric CO2 content plays an important internal feedback role. Orbital-scale variability in CO2 concentrations over the last several hundred thousand years covaries (Figure 5.3) with variability in proxy records including recon- structions of global ice volume (Lisiecki and Raymo, 2005), climatic conditions in central Asia (Prokopenko et al., 2006), tropical (Herbert et al., 2010) and Southern Ocean SST (Pahnke et al., 2003; Lang and Wolff, 2011), Antarctic temperature (Parrenin et al., 2013), deep-ocean temperature (Elder eld et al., 2010), biogeochemical conditions in the North Paci c (Jaccard et al., 2010) and deep-ocean ventilation (Lisieckiet al., 2008). Such close linkages between CO2 concentration and climate variability are consistent with modelling results suggesting with high confidence that glacial–interglacial variations of CO2 and other GHGs explain a considerable fraction of glacial–interglacial climate variability in regions not directly affected by the NH continental ice sheets (Timmermann et al., 2009; Shakun et al., 2012).

Great points

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Posted: 29 July 2017 08:53 PM   [ Ignore ]   [ # 24 ]
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JohnH - 20 July 2017 11:17 AM

The little ice age occurred only 400 years ago accompanied by a temperature fall of less than 1 degree. I’m talking about events that happened more than 100,000 years ago and involved temperatures dropping 5 degrees. There doesn’t seem to be solid explanations why that happened.

Actually there is a well established explanation for the changes of climate from glacial and inter-glacial periods.

http://www.indiana.edu/~geol105/images/gaia_chapter_4/milankovitch.htm

The episodic nature of the Earth’s glacial and interglacial periods within the present Ice Age (the last couple of million years) have been caused primarily by cyclical changes in the Earth’s circumnavigation of the Sun. Variations in the Earth’s eccentricity, axial tilt, and precession comprise the three dominant cycles, collectively known as the Milankovitch Cycles for Milutin Milankovitch, the Serbian astronomer and mathematician who is generally credited with calculating their magnitude. Taken in unison, variations in these three cycles creates alterations in the seasonality of solar radiation reaching the Earth’s surface. These times of increased or decreased solar radiation directly influence the Earth’s climate system, thus impacting the advance and retreat of Earth’s glaciers.

It is of primary importance to explain that climate change, and subsequent periods of glaciation, resulting from the following three variables is not due to the total amount of solar energy reaching Earth. The three Milankovitch Cycles impact the seasonality and location of solar energy around the Earth, thus impacting contrasts between the seasons.

We already have mike yohe here to play the idiot when it comes to climate change, we really don’t need another

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Posted: 29 July 2017 09:20 PM   [ Ignore ]   [ # 25 ]
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JohnH - 27 July 2017 10:24 PM

CC, the reason I ignore you is that you approach debate in a hostile, obnoxious manner, responding more to your perceptions of disagreement rather than issues raised, presumably triggered by prejudices you cannot control. As a consequence, you have disrupted rather than contributed to substantive debate. Your debating style is contrary to forum rules (for example, personal attacks, suggesting I’ve joined the fools bandwagon or describing my comments as “bullshit” without any convincing explanation why. Even starting new threads in an effort to bait me.). So, yes, I choose for the most part to ignore you.
For anyone with a more level-headed interest here is an image relating several climate variables.dn11640-1_800.jpg
You may note that insolation is not well correlated with other changes. As far as I understand, attempts to incorporate Milankovitch cycles into climate simulations (climate models) have not provided a good fit with real data. If I am mistaken, references to reports of the success of such simulations will be much more convincing than simply characterizing my comments (possibly based on ignorance) as “bullshit” without any real evidence to back up the accusation. That is a violation of forum rules.
You may note that recent temperatures (the red line at the left side of the graph) have fluctuated within a 2 degree range for the last 10,000 years. About 20,000 years ago temperatures were 8 degrees cooler than those recent temperatures. The Little Ice Age occurred a few hundred years ago and isn’t even noticeable in the recent temperature fluctuations, so no, my focus isn’t the little ice age.
At least one of the temperature spikes at 125,000 240,000 and 320,000 years ago is higher that the IPCC projection for 2050. Other graphs show it more clearly, for example the Wikipedia paleoclimate entry. This is the source of my concern that natural climate changes may have the apparently unrecognized potential to add even more to our global warming problem. This isn’t denying or minimizing anthropogenic warming - it is a concern that we could be facing a double-whammy that we don’t seem to be prepared for.
You may also note the similarities between carbon dioxide and temperature changes in the last 4 temperature cycles. This means that carbon dioxide levels fell (naturally?) In previous climate cycles. The simple question in the OP to this thread was if anyone can point to what triggered this reversal. A further question may be what sources existing to support any explanations. By that I mean hard evidence along the lines of GCMs, not arm-waving generalities or opinion pieces by, for example a cognitive science graduate in a Department of Communication as is John Cook who runs the skeptical science website.
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Another obvious climate change denier which means a total intellectual fraud.

I’m blocking this latest attempt to kill us all by blocking the actions needed to mitigate the very real threat of human forced climate change.

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Posted: 29 July 2017 11:18 PM   [ Ignore ]   [ # 26 ]
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CC, why do you beat around the bush? Having trouble answering JohnH question directly? What you seem to want to play here is a game of look what I can post. You win. You always win when it comes to who can post the most links. With over 10,000 papers on climate change filed each year. You can find backing for any idea you want. For example, DougC claims that climate change is created by the rich and the tobacco industry. Then when Trump was elected, he is creating climate change.
 
There is nothing wrong with saying, “We don’t really know for sure”.
 
Point being. In today’s news, this article by an atmospheric scientist about how the models can’t yet explain how clouds work. And yet I can find thousands of articles explaining how the clouds work. Yet this atmospheric scientist claims that “People have been guessing for years, but not everybody agrees”. Meaning that the data for how clouds work needs to be established before the computer models can work.
Cloud physics could be the key to understanding climate change
qz.com/1034370/the-weather-in-dominica-isnt-as-it-appears-and-the-clouds-that-form-there-could-change-our-predictions-of-climate-change/
 
Most people of knowledge understand that when people resort to name-calling they are propagandists who use this technique hoping people will reject ideas base on the negative remarks instead of looking at the evidence with logic.

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Posted: 30 July 2017 07:30 AM   [ Ignore ]   [ # 27 ]
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MikeYohe - 29 July 2017 11:18 PM

CC, why do you beat around the bush? Having trouble answering JohnH question directly?

What direct question?
http://www.centerforinquiry.net/forums/viewthread/19424/#234548
I also directly responded to his opening queries with explanation about the fact that Atmospheric physics has been nailed -
Where the confusion comes in is in measuring how its being circulated and stored around our planet.
I explained some of the main factors at play.
What more do you want?

Citizenschallenge-v.3 - 20 July 2017 07:36 PM
JohnH - 20 July 2017 11:17 AM

The little ice age occurred only 400 years ago accompanied by a temperature fall of less than 1 degree. I’m talking about events that happened more than 100,000 years ago and involved temperatures dropping 5 degrees. There doesn’t seem to be solid explanations why that happened.

The hell there aren’t, you just haven’t tried finding anything and seriously learning about it.

Plus you delude yourself into thinking you can skip the physics of greenhouse gases and still arrive at any satisfactory answers about paleoclimatology.
Can’t be done.  That only works in the Alt-reality of politically passionate liars.

IPCC - 5th assessment - Climate Change 2013: The Physical Science Basis
Information from Paleoclimate Archives
http://www.ipcc.ch/pdf/assessment-report/ar5/wg1/WG1AR5_Chapter05_FINAL.pdf

The Discovery of Global Warming          
A hypertext history of how scientists came to (partly)(that’s science speak for there’s always more to learn) understand what people are doing to cause climate change.
https://history.aip.org/climate/index.htm

If you think I’m doing a shit job of answering, then be more specific and less devious in your own utterances and supposed questions.
Oh and also respond as though you actually spent a moment consider what I’m sharing.
 
Because I am doing my best to explain in a good faith manner - intellectual honesty and better understanding our planet is what’s paramount,
it’s not about me or my course grain.
that’s why I’ve dedicated my entire life to learning about this wonderful planet, it’s history and it’s reality.

[ Edited: 30 July 2017 10:17 AM by Citizenschallenge-v.3 ]
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Posted: 30 July 2017 10:02 AM   [ Ignore ]   [ # 28 ]
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This response is actually intended more for any students of the Tactics of Denial, rather than this disingenuous crazy-maker who avoids every serious point made with smoke screens of distractions all intended to raise uncertainty and confusion, rather than to resolve better understanding.

Considering contrasts between a Constructive Debate v Destructive Debate.

In a Constructive Debate each side stakes their positions, then offers up citations or links to substantive sources of information.
Because the object is to help further educate each other, thereby raising the general communal aware.

In a Constructive Debate we listen to our opponents arguments, look at their evidence, evaluate it as objectively as possible in light of one’s own experiences and understanding.

Once we digest our opponents position and evidence, then we respond by first,
Honestly retelling and representing your opponents position, then,
responding to your opponents stated position and facts, rather than distracting with emotionalizing rhetoric.

MikeYohe - 29 July 2017 11:18 PM

CC, why do you beat around the bush?  Having trouble answering JohnH question directly? 

Beating around the bush?  Pray tell please do explain.

If I have been unclear, a serious debater would enunciate my failings - offer specific critique and further questions.
Instead, you offer up another rhetorical slap in the face and then proceed straight back to your Dog-Chasing-Tail game.

Here we see MikeYohe, et al.‘s Big Lie in action:
If having 95% accurate/complete understanding is the best we can hope for and if we have only achieved 90% understanding - they believe they have a right to ridicule, dismiss and ignore all that scientists have gotten an extremely excellent understanding of.  That’s dishonest in the extreme.

MikeYohe - 29 July 2017 11:18 PM

What you seem to want to play here is a game of look what I can post. You win. You always win when it comes to who can post the most links. With over 10,000 papers on climate change filed each year. You can find backing for any idea you want.

Providing links to resources that explain why scientists have an exquisite understanding of atmospheric GHG physics, ...
Providing links to resources that explain why scientists have a damned clear understanding of paleoclimate and causes of various fluctuation to an amazing resolution, sure not perfect - but life has never ever ever behaved that why what the hell gives the GOP et. al state demanding absolutely complete and perfect understanding of every nuance and detail of our climate engine.

Providing links that explain that it’s more than “The Sun” and minor variations in insolation -
it’s also about heat distribution and the many factors that play a hand in that,
the Earth’s atmosphere, oceans, cryosphere, landmasses.

MikeYohe - 29 July 2017 11:18 PM

For example, DougC claims that climate change is created by the rich and the tobacco industry. Then when Trump was elected, he is creating climate change.

This is funny, notice how Mike waltzes right past the fact that there is mountains of evidence, proof, supporting those claims and assertions.  Why refuse to digest that reality???
Fact isn the conceivers of the Tobacco PR game switched to Anthropogenic Global Warming (and “environmentalism” among others.) (That’s what we called it back when most folks still had their feet planted on the ground, rather than lost in cyber-space of self-inflicted fantasy, as we are these days.) 

It is solid reality with plenty of a solid evidence adding up to overwhelming proof.

Talk by the Harvard Historian, Naomi Oreskes - about her book Merchants of Doubt
Published on Apr 16, 2012 - Pirate Television:
https://www.youtube.com/watch?v=LNPRgR-2o-A

Political sectors that do not support the concerns of global warming emphasize scientific uncertainty and insist there is no consensus about global warming. Scientific communities since 1995 have claimed the balance of evidence suggests a discernible human impact on global climate. Doubt mongering that was used in the tobacco industry is now used on environmental issues as a way to make the science on global warming look unsettled. Around 700 billion dollars annually is spent to bailout fossil fuel industries.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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Posted: 30 July 2017 10:03 AM   [ Ignore ]   [ # 29 ]
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(One of these days gonna have to watch the documentary, I did read the book wink)

Stunning film exposes climate sceptics #MerchantsOfDoubt
Climate State - Published on Aug 30, 2016
https://www.youtube.com/watch?v=pRenGy0cg5s&t=319s

Merchants of Doubt is a 2014 American documentary film directed by Robert Kenner and inspired by the 2010 book of the same name by Naomi Oreskes and Erik M. Conway. The film traces the use of public relations tactics that were originally developed by the tobacco industry to protect their business from research indicating health risks from smoking. The most prominent of these tactics is the cultivation of scientists and others who successfully cast doubt on the scientific results. 

Yes, and as Doug pointed out the future exacerbation of our global warming crisis into an even faster growing and more hideously disruption and degradation of our biosphere, that we’ll be able to lay at the Trump Puppet’s feet - though he’s only a figure head for other sinister forces.

There is nothing wrong with saying, “We don’t really know for sure”.

The fuk there isn’t,if you are lying about all that is know,... 
If you are setting impossible expectations, ...
If that “for sure” becomes a justification for doing nothing in the face of overwhelming evidence both physical and theoretical, ...
Then yes that is wrong as hell.

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Posted: 31 July 2017 10:09 AM   [ Ignore ]   [ # 30 ]
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Citizenschallenge-v.3 - 30 July 2017 10:03 AM

(One of these days gonna have to watch the documentary, I did read the book wink)

Stunning film exposes climate sceptics #MerchantsOfDoubt
Climate State - Published on Aug 30, 2016
https://www.youtube.com/watch?v=pRenGy0cg5s&t=319s

Merchants of Doubt is a 2014 American documentary film directed by Robert Kenner and inspired by the 2010 book of the same name by Naomi Oreskes and Erik M. Conway. The film traces the use of public relations tactics that were originally developed by the tobacco industry to protect their business from research indicating health risks from smoking. The most prominent of these tactics is the cultivation of scientists and others who successfully cast doubt on the scientific results. 

Yes, and as Doug pointed out the future exacerbation of our global warming crisis into an even faster growing and more hideously disruption and degradation of our biosphere, that we’ll be able to lay at the Trump Puppet’s feet - though he’s only a figure head for other sinister forces.

There is nothing wrong with saying, “We don’t really know for sure”.

The fuk there isn’t,if you are lying about all that is know,... 
If you are setting impossible expectations, ...
If that “for sure” becomes a justification for doing nothing in the face of overwhelming evidence both physical and theoretical, ...
Then yes that is wrong as hell.

You are all hype. It is more about Trump than science for you.
 
If there is overwhelming physical and theoretical evidence. Then what are you waiting for? Why don’t they just shut down the IPCC? After all, you have all the answers, all world has to do is ask you, and you will tell them.
   
It has been established that the problem is caused by over population.  Something that you never talk about. Trump, yes, every chance your get. Solution to the problem, never.

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