THE DEMISE OF SUNSPOTS—DEEP COOLING AHEAD?
Don J. Easterbrook, Professor of Geology, Western Washington University, Bellingham, WA
The three studies released by NSO’s Solar Synoptic Network this week, predicting the virtual vanishing of sunspots for the next several decades and the possibility of a solar minimum similar to the Maunder Minimum, came as stunning news. According to Frank Hill,
“the fact that three completely different views of the Sun point in the same direction is a powerful indicator that the sunspot cycle may be going into hibernation.”
The last time sunspots vanished from the sun for decades was during the Maunder Minimum from 1645 to 1700 AD was marked by drastic cooling of the climate and the maximum cold of the Little Ice Age.
What happened the last time sunspots disappeared?
Abundant physical evidence from the geologic past provides a record of former periods of global cooling. Geologic records provide clear evidence of past global cooling so we can use them to project global climate into the future—the past is the key to the future. So what can we learn from past sunspot history and climate change?
Galileo’s perfection of the telescope in 1609 allowed scientists to see sunspots for the first time. From 1610 A.D. to 1645 A.D., very few sunspots were seen, despite the fact that many scientists with telescopes were looking for them, and from 1645 to 1700 AD sunspots virtually disappeared from the sun (Fig. 1). During this interval of greatly reduced sunspot activity, known as the Maunder Minimum, global climates turned bitterly cold (the Little Ice Age), demonstrating a clear correspondence between sunspots and cool climate. After 1700 A.D., the number of observed sunspots increased sharply from nearly zero to more than 50 (Fig. 1) and the global climate warmed.
The Maunder Minimum was not the beginning of The Little Ice Age—it actually began about 1300 AD—but it marked perhaps the bitterest part of the cooling. Temperatures dropped ~4º C (~7 º F) in ~20 years in mid-to high latitudes. The colder climate that ensued for several centuries was devastating. The population of Europe had become dependent on cereal grains as their main food supply during the Medieval Warm Period and when the colder climate, early snows, violent storms, and recurrent flooding swept Europe, massive crop failures occurred. Winters in Europe were bitterly cold, and summers were rainy and too cool for growing cereal crops, resulting in widespread famine and disease. About a third of the population of Europe perished.
Glaciers all over the world advanced and pack ice extended southward in the North Atlantic. Glaciers in the Alps advanced and overran farms and buried entire villages. The Thames River and canals and rivers of the Netherlands frequently froze over during the winter. New York Harbor froze in the winter of 1780 and people could walk from Manhattan to Staten Island. Sea ice surrounding Iceland extended for miles in every direction, closing many harbors. The population of Iceland decreased by half and the Viking colonies in Greenland died out in the 1400s because they could no longer grow enough food there. In parts of China, warm weather crops that had been grown for centuries were abandoned. In North America, early European settlers experienced exceptionally severe winters.
So what can we learn from the Maunder? Perhaps most important is that the Earth’s climate is related to sunspots. The cause of this relationship is not understood, but it definitely exists. The second thing is that cooling of the climate during sunspot minima imposes great suffering on humans—global cooling is much more damaging than global warming.
Global cooling during other sunspot minima
The global cooling that occurred during the Maunder Minimum was neither the first nor the only such event. The Maunder was preceded by the Sporer Minimum (~1410–1540 A.D.) and the Wolf Minimum (~1290–1320 A.D.) and succeeded by the Dalton Minimum (1790–1830), the unnamed 1880–1915 minima, and the unnamed 1945–1977 Minima (Fig. 2). Each of these periods is characterized by low numbers of sunspots, cooler global climates, and changes in the rate of production of 14C and 10Be in the upper atmosphere. As shown in Fig. 2, each minimum was a time of global cooling, recorded in the advance of alpine glaciers.
The same relationship between sunspots and temperature is also seen between sunspot numbers and temperatures in Greenland and Antarctica (Fig. 3). Each of the four minima in sunspot numbers seen in Fig. 3 also occurs in Fig. 2. All of them correspond to advances of alpine glaciers during each of the cool periods.
Figure 4 shows the same pattern between solar variation and temperature. Temperatures were cooler during each solar minima.
What can we learn from this historic data? Clearly, a strong correlation exists between solar variation and temperature. Although this correlation is too robust to be merely coincidental, exactly how solar variation are translated into climatic changes on Earth is not clear. For many years, solar scientists considered variation in solar irradiance to be too small to cause significant climate changes. However, Svensmark (Svensmark and Calder, 2007; Svensmark and Friis-Christensen, 1997; Svensmark et al., 2007) has proposed a new concept of how the sun may impact Earth’s climate. Svensmark recognized the importance of cloud generation as a result of ionization in the atmosphere caused by cosmic rays. Clouds reflect incoming sunlight and tend to cool the Earth. The amount of cosmic radiation is greatly affected by the sun’s magnetic field, so during times of weak solar magnetic field, more cosmic radiation reaches the Earth. Thus, perhaps variation in the intensity of the solar magnetic field may play an important role in climate change.
Are we headed for another Little Ice Age?
In 1999, the year after the high temperatures of the 1998 El Nino, I became convinced that geologic data of recurring climatic cycles (ice core isotopes, glacial advances and retreats, and sun spot minima) showed conclusively that we were headed for several decades of global cooling and presented a paper to that effect (Fig. 5). The evidence for this conclusion was presented in a series of papers from 2000 to 2011 (The data are available in several GSA papers, my website, a 2010 paper, and in a paper scheduled to be published in Sept 2011). The evidence consisted of temperature data from isotope analyses in the Greenland ice cores, the past history of the PDO, alpine glacial fluctuations, and the abrupt Pacific SST flips from cool to warm in 1977 and from warm to cool in 1999. Projection of the PDO to 2040 forms an important part of this cooling prediction.
Figure 5. Projected temperature changes to 2040 AD. Three possible scenarios are shown: (1) cooling similar to the 1945-1977 cooling, cooling similar to the 1880-1915 cooling, and cooling similar to the Dalton Minimum (1790-1820). Cooling similar to the Maunder Minimum would be an extension of the Dalton curve off the graph.
So far, my cooling prediction seems to be coming to pass, with no global warming above the 1998 temperatures and a gradually deepening cooling since then. However, until now, I have suggested that it was too early to tell which of these possible cooling scenarios were most likely. If we are indeed headed toward a disappearance of sunspots similar to the Maunder Minimum during the Little Ice Age then perhaps my most dire prediction may come to pass. As I have said many times over the past 10 years, time will tell whether my prediction is correct or not. The announcement that sun spots may disappear totally for several decades is very disturbing because it could mean that we are headed for another Little Ice Age during a time when world population is predicted to increase by 50% with sharply increasing demands for energy, food production, and other human needs. Hardest hit will be poor countries that already have low food production, but everyone would feel the effect of such cooling. The clock is ticking. Time will tell!
References
D’Aleo, J., Easterbrook, D.J., 2010. Multidecadal tendencies in Enso and global temperatures related to multidecadal oscillations: Energy & Environment, vol. 21 (5), p. 436–460.
Easterbrook, D.J., 2000, Cyclical oscillations of Mt. Baker glaciers in response to climatic changes and their correlation with periodic oceanographic changes in the Northeast Pacific Ocean: Geological Society of America, Abstracts with Programs, vol. 32, p.17.
Easterbrook, D.J., 2001, The next 25 years; global warming or global cooling? Geologic and oceanographic evidence for cyclical climatic oscillations: Geological Society of America, Abstracts with Programs, vol. 33, p.253.
Easterbrook, D.J., 2005, Causes and effects of late Pleistocene, abrupt, global, climate changes and global warming: Geological Society of America, Abstracts with Programs, vol. 37, p.41.
Easterbrook, D.J., 2006, Causes of abrupt global climate changes and global warming; predictions for the coming century: Geological Society of America, Abstracts with Programs, vol. 38, p. 77.
Easterbrook, D.J., 2006, The cause of global warming and predictions for the coming century: Geological Society of America, Abstracts with Programs, vol. 38, p.235-236.
Easterbrook, D.J., 2007, Geologic evidence of recurring climate cycles and their implications for the cause of global warming and climate changes in the coming century: Geological Society of America Abstracts with Programs, vol. 39, p. 507.
Easterbrook, D.J., 2007, Late Pleistocene and Holocene glacial fluctuations; implications for the cause of abrupt global climate changes: Geological Society of America, Abstracts with Programs, vol. 39, p.594
Easterbrook, D.J., 2007, Younger Dryas to Little Ice Age glacier fluctuations in the Fraser Lowland and on Mt. Baker, Washington: Geological Society of America, Abstracts with Programs, vol. 39, p.11.
Easterbrook, D.J., 2007, Historic Mt. Baker glacier fluctuations—geologic evidence of the cause of global warming: Geological Society of America, Abstracts with Programs, vol. 39, p. 13.
Easterbrook, D.J., 2008, Solar influence on recurring global, decadal, climate cycles recorded by glacial fluctuations, ice cores, sea surface temperatures, and historic measurements over the past millennium: Abstracts of American Geophysical Union Annual Meeting, San Francisco.
Easterbrook, D.J., 2008, Implications of glacial fluctuations, PDO, NAO, and sun spot cycles for global climate in the coming decades: Geological Society of America, Abstracts with Programs, vol. 40, p. 428.
Easterbrook, D.J., 2008, Correlation of climatic and solar variations over the past 500 years and predicting global climate changes from recurring climate cycles: Abstracts of 33rd International Geological Congress, Oslo, Norway.
Easterbrook, D.J., 2009, The role of the oceans and the Sun in late Pleistocene and historic glacial and climatic fluctuations: Geological Society of America, Abstracts with Programs, vol. 41, p. 33.
Eddy, J.A., 1976, The Maunder Minimum: Science, vol. 192, p. 1189–1202.
Hoyt, D.V. and Schatten, K.H., 1997, The Role of the sun in climate change: Oxford University, 279 p.
Svensmark, H. and Calder, N., 2007, The chilling stars: A new theory of climate change: Icon Books, Allen and Unwin Pty Ltd, 246 p.
Svensmark, H. and Friis-Christensen, E., 1997, Variation of cosmic ray flux and global cloud coverda missing link in solar–climate relationships: Journal of Atmospheric and SolareTerrestrial Physics, vol. 59, p. 1125–1132.
Svensmark, H., Pedersen, J.O., Marsh, N.D., Enghoff, M.B., and Uggerhøj, U.I., 2007, Experimental evidence for the role of ions in particle nucleation under atmospheric conditions: Proceedings of the Royal Society, vol. 463, p. 385–396.
Usoskin, I.G., Mursula, K., Solanki, S.K., Schussler, M., and Alanko, K., 2004, Reconstruction of solar activity for the last millenium using 10Be data: Astronomy and Astrophysics, vol. 413, p. 745–751.
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UPDATE: Bob Tisdale has posted a rebuttal. Here is what he has to say via email.
Hi Anthony: The following is a link to my notes on the Easterbrook post:
We should have progressed beyond using outdated TSI datasets, misrepresenting the PDO, and creating bogus global temperature graphs in our arguments against AGW.
I’ve advised Easterbrook, and we’ll see what he has to say – Anthony
Smokey said:
And John B’s psychological projection, calling the posting of more than a half dozen charts from different sources “cherry picking” is a failed tactic that can be applied to any chart. That is why I post so many different charts; so people can make up their minds based on plenty of evidence.
Just because you have a large bowl of cherries to pick from does not stop them being cherries. You post 7 cities, I post the Northern Hemisphere. You post 8 years, I post 1000. See the difference? So, then you start saying that everything I posted was “lying”. Only I didn’t get them from my only personal bowl of cherries, they all came straight from their respective sources.
And then, having happily claiming significance for a chart showing about 200 days (for Pete’s sake), you say that the satellite record of Arctic ice extent from 1979 to 2011 is not enough to show a trend. I quote you, “Thus, your extremely short ‘record’ is meaningless.” Amazing!
And you never actually said what was wrong with this:
http://www.ncdc.noaa.gov/paleo/ei/ei_image/highlat.gif
You muttered something about Mann, but what is actually wrong with the chart? It shows a 50-year running average, which is a lot more honest than your poorly fitted linear trend. Or does it only look that way to me because I am a “true believer”?
I am confused. Are you ideologically driven to convince yourself and others that the science is flawed because you don’t like the perceived political outcomes, or do you really believe what you are saying?
“So, there is good evidence that the UV and TSI was not significantly lower during the Maunder Minimum.”
I note the word ‘significantly’ which rather neatly avoids the issue.
All that is neceesary is to shift the net balance of ozone creation/destruction above 45 Km so as to raise or lower the atmospheric heights. Such a raising or lowering alters the surface pressure distribution, cloudiness and albedo.
I see no assessments as to what would be ‘significant’ in such a scenario.
We are here dealing with a set of finely balanced chemical processes and NOT radiative physics.
Smokey says
“There is a deliberate international plan to eliminate most of the terrestrial temperature recording stations”
I also picked up something strange as well.
There is no way the Gibraltar (UK) results that I got can be correct if you carefully compare it to the results of two neighbouring Spanish weather stations and the Moroccan station opposite the strait.
http://www.letterdash.com/HenryP/what-hanky-panky-is-going-on-in-the-uk
The Gibraltar station shows no incease in maxima whereas the other three stations show an average increase of 0.04 degrees C/ annum in the maximum tempratures.
I cannot come to no other conclusion but that the data from Gibraltar must have been manipulated.
Henry@Stephen Fisher
thx for your prompt reply!
I have printed your article. Give me some time on that.
Stephen Wilde says:
June 18, 2011 at 9:15 am
“So, there is good evidence that the UV and TSI was not significantly lower during the Maunder Minimum.”
I note the word ‘significantly’ which rather neatly avoids the issue.
It means that there is no significant difference, and we therefore can’t even say if it is lower or higher. It could even be a tad higher during the MM [e.g. with no sunspots to take a bite out of TSI].
I see no assessments as to what would be ‘significant’ in such a scenario.
If TSI and UV were higher during MM, what would that do to your model?
HenryP says @ur momisugly June 18, 2011 at 8:54 am “In this game, who will always win in the end? The truth or the lies?”
Sorry – but I do not understand how that answers the question. Maybe the question wasn’t clear – just in case here it is again.
HenryP – Do you believe that only land based weather stations should be used for drawing conclusions?
What do you think Smokey?
Smokey says @ur momisugly June 18, 2011 at 9:11 am “There is a deliberate international plan to eliminate most of the terrestrial temperature recording stations”
Wow – that sounds like really unscientific plan. I’d like to read more about that. Maybe we can start with your citation of the NOAA plan that maps out their stated policy to “eliminate most of the terrestrial temperature recording stations”.
Thanks in advance for the citation, should be an interesting read.
Henry@moderaterepuclan
I think I would also (desperately) want to look at the places that record the temps of the oceans at the same place and depth every day (going back 40 years in time) . Can you help as to where to find these records?? Anyone?
John B says:
“I am confused.”
Truly. The hokey stick chart John B posted is simply wrong. Here is the radiosonde record. And monthly global temperatures are not changing. Further, the recent trend is down.
John B also complained that the charts I posted were more recent – forgetting that those charts come from alarmist sources. So he’s complaining about people who believe what he believes.
Since John B wants charts with a longer time line, he should study these:
click1
click2
click3
click4
click5
click6
click7
click8
click9
click10
As the last chart shows, there is nothing unusual about the current global temperature. A mild rise of 0.7°C over a century and a half is well within the parameters of normal climate variability. The coincidental rise of CO2 has been seized upon by vested interests to claim that CO2 is the cause. But that spurious relationship has consistently broken down, as the past decade’s falling temperatures make clear.
Finally, JB’s linked version of Michael Mann’s debunked hokey stick chart is simply a copy of the chart that the IPCC can no longer use, because McIntyre and McKittrick have effectively falsified it – to the the extent that Nature was forced to issue a correction.
Of course, John B will accept none of this because his mind is clouded by the cognitive dissonance of a true believer. But others can look at these charts from various sources and make up their own minds.
“If TSI and UV were higher during MM, what would that do to your model?”
That depends on HOW the solar changes alter the chemical balances.
The limited evidence currently available suggests that a more active sun depletes ozone above 45Km and a less active sun allows it to recover.
The actual balance and mix of wavelengths and particles required to achieve that outcome is currently not known.
So if one accepts ANY difference in the mix between MM and now then that difference can account for the differing vertical atmospheric temperature profiles.
HenryP says @ur momisugly June 18, 2011 at 9:56 am “I think I would also (desperately) want to look at the places that record the temps of the oceans at the same place and depth every day (going back 40 years in time) . Can you help as to where to find these records?? Anyone?”
Wow – my keyboard must be showing very different words that what you are seeing because your response looks to be avoiding answering a simple question. Hopefully the words I am typing here will read more clearly this time.
HenryP – Do you believe that only land based weather data should be used for drawing conclusions?
Yes or no?
Moderate Republican,
Do your own homework, I don’t accept assignments from people whose minds are made up and closed tight. I gave you solid evidence that temperature stations are being rapidly eliminated, leaving most stations in UHI environments. That is more than enough evidence of a deliberate plan for normal folks.
Smokey says @ur momisugly June 18, 2011 at 10:16 am ” I gave you solid evidence that temperature stations are being rapidly eliminated, leaving most stations in UHI environments. That is more than enough evidence of a deliberate plan for normal folks.”
Sorry Smokey – I must be missing a couple things here. Supporting assertions made here wouldn’t see to be an assignment would it? I mean when you ask for evidence from people you cannot be making an assignment to them right, otherwise you would be behaving in a totally hypocritical way an goodness knows that would not be something you do.
Given your no doubt studied conclusion there had to be multiple plans including that from NOAA that documents their stated policy to “eliminate most of the terrestrial temperature recording stations.
Given your conclusion, which clearly had to be based on facts, surely you have citations handy, no? I am sure you are very busy so why not start with just NOAA as part of the international effort to do this.
Thanks again for sending those along, they should be interesting reading and help inform the discussion here,
Moderate Republican says:
Do you believe that only land based weather data should be used for drawing conclusions?
Can I ask you first
What conclusion(question) do you want (answered)?
Stephen Wilde says:
June 18, 2011 at 10:01 am
That depends on HOW the solar changes alter the chemical balances.
The actual balance and mix of wavelengths and particles required to achieve that outcome is currently not known.
So, your model does not know what the outcome will be.
So if one accepts ANY difference in the mix between MM and now then that difference can account for the differing vertical atmospheric temperature profiles.
ANY? how about an increase during MM of UV of 0.000000000000000000000000000000001 %?
Moderate Republican,
I post what I want, not for you – you are a crank – but for others who are easily convinced by relevant facts.
The issue of declining temperature stations has been thoroughly discussed here at WUWT. It is not my job to bring you up to speed on the subject. There is an archive search feature for that. Do your own homework.
“So, your model does not know what the outcome will be.”
On the limited data available the outcome is less ozone above 45Km when the sun is active and more when the sun is inactive. The bit that is not known is the combination of circumnstances (beyond the simple level of activity) from which that outcome is derived.
“ANY? how about an increase during MM of UV of 0.000000000000000000000000000000001 %?”
If that is all it takes then so be it. However I think you have chosen a daft figure just to serve up a meaningless debating point.
@Smokey
I looked at your 10 charts. Here is my assessment:
click1 – unlabeled, can’t comment
click2 – unlabeled, can’t cpmment
click3 – ~10 years (cherry-pick)
click4 – USA only (cherry-pick)
click5 – ~10 years (cherry-pick)
click6 – at best cherry-picked, at worst manipulated (2010 was a statistical tie with 2005 in HadCRUT)
click7 – USA only (cherry-pick)
click8 – actually does show the trend, though the cock-eyed y-axis tries to hide it
click9 – actually shows the trend quite well
click10 – shows that the shaft of the hockey stick is pretty flat (as every hockey stick shows), but does not address the period of the instrumental record, i.e. the blade
Apologies in advance if I am “off by one” or anything, but you get the idea.
And on Mann vs. M&M, read the literature. The “correction” they offered was to expand ther methodological details, to stop M&M incorrectly reworking their analysis. And, as it says in the Heartland Institute article you link to (no politics there, then), “None of these errors affect our previously published results.” Of course, M&M contested that, but my question is to you is, why are you not skeptical of M&M?
Like I said before, if you don’t like Mann, look at another hockey stick. I would be more skeptical of Mann if there weren’t plenty of other studies saying the same thing. But they all do say the same thing. What does that tell you?
http://noconsensus.files.wordpress.com/2008/09/mann-graph.jpg?w=762&h=708
(wish I could find my original link, this one is to a contrarian blog, but the image is the same)
And so what if your charts “come from alarmist sources”? A cherry picked from your neighbours garden is still a cherry.
Smokey says @ur momisugly June 18, 2011 at 10:55 am “I post what I want, not for you – you are a crank – but for others who are easily convinced by relevant facts.”
I must be missing something, because this kinda looks like you don’t actually have the citations from NOAA and others that there is a deliberate plan “eliminate most of the terrestrial temperature recording stations.” And without citations it is kinda just an unsupported assertion.
All I am asking for is the relevant facts – not sure why that makes anyone simply asking for a citation a crank.
Stephen Wilde says:
June 18, 2011 at 10:55 am
“So, your model does not know what the outcome will be.”
On the limited data available the outcome is less ozone above 45Km when the sun is active and more when the sun is inactive. The bit that is not known is the combination of circumnstances (beyond the simple level of activity) from which that outcome is derived.
The more important thing that is not known is a quantification of your ‘model’. It is not known [you don’t now] how big the effect [a number] will be for active [a number] or inactive [a number] sun and how much less or more ozone is required. So you do not know whether the MM would be any different from today and how much.
If that is all it takes then so be it.
No, because you are assuming that the MUST be an effect no matter how small the stimulus is [your ANY]. I’m saying that below a certain stimulus there will be no observable [i.e. significant] effect.
Just to come back to the sun though
(thank God for WUWT where we are allowed to stray a bit!!!!)
HenryP says:
June 17, 2011 at 9:02 am
I think we can survive another little ice age… I think it is just a matter of us making sure that earth will not get “too white” (no racist pun intended). We can do that in the same way as they are removing snow in the nordic countries (salt) or employiing more and better laser beam technology directed to melt snow layers in areas where there are largely thin layers of snow (by using aeroplanes)
==================================================
Somebody (difficult name) answered :
That would have very little impact on growing seasons or desertification. Those issues would still exist, millions if not billions would perish. We live in a very populated world with JIT supply chains. There is no buffer.
—————————————————————————————-
My point here was that the “ice age trap” is simply that too much light is reflected off from earth because of there being too much snow (and white ice) present which in turn makes it even cooler still. It becomes a circle of being caught in snow and ice because the fainter sun has initially produced more snow and ice. That being the case, I think modern man can think of preventative measures to ensure that earth does not fall back into that trap of an ice age.Just don’t let it get too white. Let’s keep it blue and green, shall we?
Am I crazy or what?
HenryP says @ur momisugly June 18, 2011 at 10:32 am “Can I ask you first What conclusion(question) do you want (answered)?”
No conclusion in mind obviously, since having a conclusion in mind and then backing into that via selective data is a huge no-no, isn’t it?
So here is the question again since it seems to not be showing clearly on your screen. (which is just weird).
Do you believe that only land based weather data should be used for drawing conclusions? Yes or no?
@Mod Rep and Smokey:
I think this explains it…
http://www.ncdc.noaa.gov/crn/programoverview.html
Sorry MR
I don’t have time for playing games. I am going to bed.
If you don’t know what you want I cannot help you.
If you want to know as to how my investigations progessed (and are still progressing) after watching Al Gore’s movie “An inconvenient truth” and deciding to check it out,
just go ahead and read it all here:
http://www.letterdash.com/HenryP/more-carbon-dioxide-is-ok-ok
I am sure there is something that you can learn.
If you have still have questions after that, I am sure you can leave it there.
Moderate Republican,
I note that you consistently ignored my repeated requests to produce testable, measurable, empirical evidence, per the scientific method, showing global harm due specifically to CO2. And after ignoring those requests, you then demand that I must produce for your edification what is in the WUWT archives. Projection, much? The fact is that you can not produce real world evidence of global damage from CO2, because there is no such evidence.
And since there is no evidence of global harm from CO2, then reasonable people will conclude that CO2 is harmless. But you cannot admit that fact, because your entire belief system is based on the nonsense that CO2 is harmful. Without “carbon” to demonize, the whole CO2=CAGW conjecture comes apart at the seams, and your religion has lost it’s demon. And with nothing to hate and fear, your CAGW religion is rapidly losing converts.
# # #
John B:
You post one link to a chart — and then you label my dozens of charts, from numerous sources in multiple posts, covering numerous different time frames — as cherry picking??? If it wasn’t for psychological projection, you wouldn’t have much to say. You are just like another poster who argued that some charts I linked to were not convincing. So I posted FIFTY charts, mostly peer reviewed and all showing the same thing. He responded just like you: he found fault with all 50 charts. Your mind is hopelessly closed to any facts which contradict your belief system. The planet could plunge into the next great Ice Age, with glaciers moving south of the Great Lakes, and you would still be trying to convince us that runaway global warming is right around the corner.
And MBH98 has been completely debunked. Whining about the Nature Correction being reported by Heartland is merely an ad hominem avoidance of the fact. The UN/IPCC can no longer use Mann’s chart. So they use very similar charts fabricated on the same bad data, which show almost no LIA, and an artificially reduced MWP. I have posted several charts based on peer reviewed data showing that the MWP was warmer than today. The chart you posted was an outright fabrication; a lie. And of course they don’t dare show the prior Holocene warming episodes, which were even warmer than the MWP. Really, if you believe the crap you posted, you will believe anything.