By Andy May
Most agree that the Milankovitch cycles of eccentricity, obliquity, and precession drive long-term global and hemispheric climate changes, see figure 4 in this post for a brief description of them. The modern climate debate is about short-term climate change. The “consensus” says that human emissions have caused “the most rapid change” or “temperatures are the warmest in X years” (Lecavalier et al., 2017) and (IPCC, 2021, p. 8) with X varying from one thousand years to over 100,000 years. Obviously, we only have global instrumental data for the past 170 years or so, so any global or hemispheric data before then is either local or proxy temperature data.
The mainstream view is to ignore inconvenient data that shows CO2 and methane air concentrations do not correlate with temperature during the Holocene Epoch, or the past 12,000 years as shown in figure 4 here. Correlation is not causation, but the lack of correlation normally precludes causation. If changes in heat storage in the climate system are ignored, as is often done, then only outside forcing can cause climate change. Since recent climate changes (since 1950) have been too rapid to be caused by the Milankovitch orbital cycles, the only outside forces left are the Sun and greenhouse gases (GHGs). Since the oceans and atmosphere change the amount of heat they store, as opposed to emit to space, climate changes as climatic heat storage changes (Irvine, 2014). We can observe this in the 60-70-year climate or ocean oscillations, like the Atlantic Multidecadal Oscillation (AMO, see here and here).
The Sun and GHGs work differently. Solar radiation penetrates the ocean surface and warms the water at depth, storing heat in the ocean. GHGs absorb radiation emitted by Earth and mostly use it to warm gas molecules near them. Infrared emissions from GHGs cannot penetrate the ocean surface (Wong & Minnett, 2018). By warming the surface, they stimulate more evaporation sending a lot of the energy back to the atmosphere, although a small portion is circulated deeper by convection. Heat stored in the oceans stays in the climate system longer than storage in the atmosphere and change climate on decadal and century time scales (Irvine, 2014). This is seen in ocean oscillations. Changes in GHGs only affect the atmosphere and can only affect climate in the very short term. Theoretically temperature changes from the top of one 11-year solar cycle to the bottom is only about 0.02°C due to the direct change in radiation reaching the Earth. However, the actual observed change is five times higher or 0.1°C and the increase in the upper atmosphere is 0.3°C. This is discussed in more detail here and (Hoyt & Schatten, 1997), (Lean, 2017), and (Haigh, 2011).
The Neoglacial
The Neoglacial period is not formally defined and its onset (that is the beginning of glacial growth in the late Holocene) varies with location. It is a global glacial advance (with the possible exception of Antarctica, see figure 1 and here) from the end of the Holocene Climatic Optimum. The important point is that the Neoglacial onset is not synchronous around the world (McKay et al., 2018). Here we begin the Northern Hemisphere Neoglacial at roughly 3,800BC, just after the Mid-Holocene Transition (MHT) from the Holocene Climatic Optimum (HCO). The literature has the Neoglacial starting anywhere from 2,000BC to 3,000BC, so my pick is a little early, but not excessively so.
When the chosen Neoglacial period begins the average latitude of the Intertropical Convergence Zone (ITCZ ) shifts dramatically southward which initiates the desertification of the Sahara. The average ITCZ latitude responds strongly to interhemispheric temperature gradients and it shifts southward when the Northern Hemisphere cools as it did around 4,700BC (see figure 1 here). For more on this dramatic change in climate see here, as well as (Wanner & Brönnimann, 2012) and (DeMenocal et al., 2000).
Regardless of complaints from the “consensus,” the Neoglacial period may not have ended yet, it is still much colder today in the Northern Hemisphere than most of the Holocene as shown in the featured image of my previous post. Given the length, strength, and depth of the Neoglacial; it is hard to call its end after only seventy years of on-and-off warming. It will take another 100 to 200 years of warming to be sure we have really and truly ended the Neoglacial.
The first part of the Holocene, until around 4,000BC was quite warm, at least according to my favorite Northern Hemisphere proxies, the Vinther air temperature proxy (shown black in figure 1) and the Rosenthal Makassar Strait 500-meter proxy of Northern Pacific sea surface temperatures (SST, shown in blue). The lower part of figure 1 shows the number of global glacial advances from (Solomina et al., 2015) as a blue line and the central time and duration of solar grand minima (SGM, black dots) and solar grand maxima (SGMx, orange dots) from (Usoskin, 2017). Before the earliest SGMx shown (at 3860BC) there is not another until 6,120BC. Thus, the Holocene Climatic Optimum (HCO) is likely due to orbital cycles as long assumed and not due to solar maxima.
The Mid-Holocene Transition and the Neoglacial begin with a cluster of six SGMs and four SGMxs, so the sun was highly variable then. It might have played a role, along with the obvious orbital insolation forcings in the initiation of the Northern Hemispheric cooling, but the pattern is ambiguous as to its net effect on climate. Likewise, the 4.2 ka (thousand years ago) climate event does not correlate with the SGM before it or the SGMx after it, it must have other causes.
The overall picture of figure 1 shows a general decline in temperature as the number of glacial advances increases. The period from 2000BC to 500BC has little solar variability, but a strong 120-year SGM at 750BC and a dramatic increase in glacial advances. Right in the middle of these advances is the Bronze Age collapse in the eastern Mediterranean. The strongest SGM is centered on 1470AD and it is accompanied with the maximum number of glacial advances, these are both just before the deepest part of the Little Ice Age from 1500 to 1750AD.
The spectacular 1177BC Bronze Age collapse (Cline, 2014) follows the 70-year SGM at 1385BC by almost 200 years, so it is unclear how much influence it might have had on that climate catastrophe. The Bronze Age collapse of eastern Mediterranean civilization led to the Greek Dark Age, and it did not end until the Roman Warm Period (RWP) began around 300BC, (some place the beginning later around 250BC). The RWP does not end until 400-500AD.
The Roman Warm Period saw the rise of the Roman Empire, the unification of China by Ch’in in 221BC, and it began just after the death of Alexander the Great. It also saw the rise of India’s greatest ancient emperor, Ashoka the Great who unified India for the first time around 266BC. Ashoka converted to Buddhism and promoted the spread of the religion. This period also includes the life of Jesus of Nazareth and the rise of Christianity.
The Roman Warm Period is notable because it coincides with three consecutive solar grand maxima and contains no solar grand minima. It is also within one of the longest periods in the Holocene without an SGM. The other such long gap, from 1385 to 2450BC, essentially marks the peak of the Bronze Age.
The European Dark Age can be identified by lower temperatures in the Vinther record between 500 and 800AD and an SGM at 690AD. The Medieval Warm Period exists between the SGM at 690AD and one at 1030AD and is more of a transitional period into the Little Ice Age than a true warm period like the RWP. The Little Ice Age has no SGMxs and four SGMs, with an exceptionally long one at 1470AD. The Vinther record reaches its coldest point at 1700AD and the North Pacific Rosenthal record is coldest at about 1810AD, so 1750AD is a reasonable Northern Hemisphere date for the modern warm period to begin. The last SGM is centered on 1680AD and it lasts from 1640 to 1720AD.
Once the last SGM is done, the next solar event is the Modern Solar Maximum centered on 1970 and from 1930 to 2010. It is the longest solar maximum since 3,170BC and the first solar maximum since 505AD.
Discussion
I am definitely not saying that solar variability is the only thing causing climate change and I do not think it is stronger than the Milankovitch orbital cycles (see figure 4 here). But, when we came out of the Little Ice Age, the coldest period in the entire Holocene Epoch, and a period with no solar grand maxima and four solar grand minima, including the strongest SGM (as measured by duration) in the Holocene, one has to consider that solar variability contributed to the Little Ice Age.
Then we must consider the Modern Warming Period. It coincides with the first solar grand maximum in 1,465 years and the strongest in 5,140 years. It seems quite reasonable to conclude that the modern solar grand maximum contributed to the observed recent climate changes. Climate change is a complex combination of the Milankovitch cycles, solar cycles, and (maybe) anthropogenic factors. It does not have just one cause at any time scale.
Download the bibliography here.
From history, being afraid of warm periods is perverse.
After spending 10 years studying climate and civilization, I totally agree with you.
Being afraid of 500 or 600 ppm of CO2 is also perverse.
“Then we must consider the Modern Warming Period. It coincides with the first solar grand maximum in 1,465 years and the strongest in 5,140 years.”
Indeed, this is where our “hockey stick blade” comes from. On the graphic and in the article, I would have added that arguably the worst drought and natural disaster in US history was the 1930s Dust Bowl, right before the modern, beneficial, warming.
The “Dust Bowl” was not entirely a “natural disaster”:
The Worst Hard Time: The Untold Story of Those Who Survived the Great American Dust Bowl―(2006), by Timothy Egan
The dust part was a lot due to farming practices. The drought that caused crop failures was natural. The original prairie grass had roots 6, 7, 8 feet deep to survive droughts. Farming here on the plains started as “dry land” farming and was dependent on rain. Still a lot of it but irrigation has increased.
Johnesm:
As with ALL warming periods, the 1930’s warming was due decreases in the amount of SO2 aerosol pollution in the atmosphere, initially due to decreased industrial activity (a decrease of 9.9 million tons between 1929 and 1932), and, later, a stalled heat dome that allowed SO2 aerosol pollution to settle out of the atmosphere, after about a week, causing temperatures to rise, and another recession, with reduced industrial activity between May 1937 and June 1938 and, between May 1937 and Feb 1943, no VEI4 volcanic eruptions to maintain SO2 aerosol pollution of the atmosphere, and temperatures rose because of the cleansed air..
Between about 1950 and 1979, temperatures cooled down because of increasing industrial SO2 aerosol pollution of the atmosphere, peaking at 139 million tons in 1979.
The later “beneficial” warming began in 1980, due to American and European “Clean Air” legislation of the 1970’s, to reduce the amount of industrial SO2 aerosol pollution of the atmosphere.
Hmmmm, once the Palaeolithic people gave up their automobiles, coal electric plants, and factories to become Neolithic hunter-gatherers the air cleaned up enough to end the last glacial period. Thanks, I didn’t know that/sarc.
Andy May:
You gave a rather poor analogy–the last glacial period ended when there were fewer volcanic eruptions and less SO2 aerosol pollution of the atmosphere to dim the Sun’s rays..
The Roman Warm period, and the MWP occurred because there were very few volcanic eruptions during those periods. For example, there only 31 VEI4 or larger eruptions during the 300 year MWP, so that there were decades when the air was completely free of any volcanic SO2 aerosols, and temperatures necessarily soared. during those intervals.
There is no single cause.
Sparta Nova:
I have not found a single instance where a significant increase or decrease in average anomalous global temperatures cannot be attributed an increase or a decrease in the amount of SO2 aerosol pollution.
Sure looks like a single cause!
Sparta Nova:
I should have added “apart from albedo or seasonal changes”
Correlation is not causation.
SO2 has an influence, but it is not the primary driver, it is not the “control knob.”
Sparta Nova 4:
With 100% correlation, it IS the control knob, as it HAS to be for the premise to be correct.
Wrong. It does not work that way.
“Two-thirds of the global warming since 2001 is sulphur dioxide reduction rather than carbon dioxide increases.”
-Peter Cox, Professor of Climate System Dynamics at the University of Exeter
GeorgeinSanDiego:
Thanks for the reference.
It is irrefutable.
Two-thirds is an estimate and as such is refutable.
Sparta Nova 4:
Not if you look at the data
Not have a means to independently verify the data, I remain skeptical.
That aside, 2/3 not 33.3%? Suspicious.
Tyndall’s experiments show that reducing the amount of radiation reaching a thermometer by increasing the amount of CO2 or H2O vapour in the radiation transmission path, results in lower, not higher, temperatures.
Fact. Supported by observations – the hottest places on Earth have the least amounts of “GHG”s.
Peter Cox is a known klimate klown. Hardly a reliable source.!
Let’s look at SO2 measure over the USA , compared to temperature trends.
(ppb numbers are estimates from the chart below, amounts added from data from someone else, I can’t remember who).
From 174ppb in 1980 to 89ppb in 1998, (a decrease of about 14.7 million tons)
UAH USA48 shows no warming or cooling
.
SO2 dropped from 79ppb in 2005 to 24ppb in 2015.. (a decrease of about 8.1 million tons)
According to USCRN and UAH USA48 there was no warming or cooling.
—-
The SO2 cooling conjecture is not supported by measured evidence over the USA.
What say you, Burl?
Tom Abbott:
I am speaking of average anomalous global temperatures. Temperatures over the USA are part of that average.
And those USA data shows SO2 does NOTHING
Correct.
Blocking sunlight would have area affects unless SO2 is uniformly present in the atmosphere in which the US would track the rest of the world.
GAT is bogus.
bnice2000:
When the VEI6 eruption of Pinatubo occurred in June 1991, US average annual temperatures dropped from 53.4 Deg. F in 1990 to 50.8 deg F in 1993, recovering to 54.7 Deg F in 1994, after its SO2 aerosols had settled out of the stratosphere.
The temperature decrease was due to the injection of 18.2 million tons of volcanic SO2 aerosols into the stratosphere over the Philippine Islands.
So you lie when you say that SO2 does nothing!
So, if my neighbor warms his home to 78 F and I keep mine at 72 F we can conclude that every house is 75 F.
Do you not see that the average is meaningless?
These facts came out of CoPilot with little prompting. “When can you average intensive properties.”
The 1930s were some of the warmest years on record–in fact fully one third of high temperature records in the Kansas City area were set in the 1930s. Modern beneficial warming has not been as warm.
“During the 1930s, the coldest areas in the USA included the Midwestern states, particularly North Dakota, South Dakota, and Nebraska, which experienced some of the coldest temperatures on record. The winter of 1935/36 was notably severe, with many regions in the northern plains facing extreme cold and harsh conditions.”
So says the internet and the book mentioned at 11:01.
John,
So, you admit that extreme weather was higher than today in the 1930s, is that what I read? Some of the highest summer temperatures in Europe were during the Little Ice Age also.
Andy May:
Between about 1721 and 1740 there was period of no VEI4 or larger volcanic eruptions, and temperatures warmed up because there was no volcanic SO2 aerosol pollution of the atmosphere.
The period from 1720 to 1740AD saw a lot of very extreme weather in Europe.
The late 1720s saw harsh conditions contributing to famines (e.g., in Ireland 1728–1729, tied to poor yields from unusual temperature and precipitation). The most dramatic event was the winter of 1739/40 (starting late 1739), one of the coldest on record in Europe—often called the “Great Frost.” It rivaled or exceeded the severity of 1708/09, with temperatures ~4°C below modern averages in places. Rivers froze deeply (e.g., Thames frost fairs, Venice lagoon, Baltic Sea, Vistula >50 cm ice), livestock and fish died, and crops (especially potatoes) were destroyed.
There were a lot of floods in this period.
The 1730s stand out as one of the warmest decades in the Central England Temperature (CET) series,
This relative warmth ended sharply. The late 1730s transitioned into one of the most extreme cold events on record: the winter of 1739/40 (starting in late 1739) was exceptionally severe across Europe, with the entire year 1740 being the coldest in central Europe in at least 600 years (around 2°C below pre-industrial averages, or over 4°C below today after modern warming). This cold persisted into much of 1740, affecting agriculture, causing famines (e.g., in Ireland), and leading to frozen rivers and widespread hardship.
Bottom line: Cold periods bring extreme weather, warmer periods (such as today) milder weather.
Andy May:
There was a VEI5 volcanic eruption (Shikotsu, on Aug 19,1739, that was responsible for the severe weather of 1740, because of its insertion of SO2 aerosols into the stratosphere. It is located in Japan.
Andy, I suggest that science is about facts, rather than cunning debating tactics.
It makes no difference to a fact whether somebody “agrees” or “disagrees”. Wouldn’t you agree?
The record cold took place during the winter.
There was record hot temperatures the following summer.
This is caused by how the jet stream configures itself. Even during a period of high heat during the decade of the 1930’s, the jet stream can still bring record cold arctic air down into the United States during the winter.
A cold winter does not mean it wasn’t hot in the 1930’s.
Modern warming is anomalous relative to the Holocene.
Most of the Holocene has been warmer than now. The LIA was anomalously cold for this interglacial.
Even if were anomalous (which it isn’t) that wouldn’t make it bad, quite the contrary.
Absurd, we haven’t even warmed to the average temperature of the Holocene.
GISP shows MANY periods of warming and cooling which are just as steep, and much more prolonged, that the tiny insignificant warming since 1900
That graph doesn’t show any data since 1900!
So the climate scientists are wrong and it has warmed by more than 2.5C since 1900. :0
A meaningless assertion.
Andy made a number of salient points regarding solar forcing, and why people think it is so limited.
Orbitally induced insolation changes are the base layer underlying irregular solar cycle forcing.
Right after the v2 sunspot numbers (SN) were first published I calculated the Modern Maximum, which later became part of my 2018 AGU poster about solar irradiance ocean warming.
The Solar Modern Maximum was when sunspot numbers were 65% higher during the 70 years from 1935-2004 than during the previous 70 years, 108.5 v2 SN, vs 65.8 v2 SN annually from 1865-1934.
The solid red line in Fig. 16 from that poster (below) at 95 sunspot number is the sun-ocean decadal warming threshold I determined in 2014, a topic also covered in the 2018 AGU poster.
The mechanisms at play during the Modern Maximum were repeated the following two solar cycles, with a decadal warming step after sunspots exceeded 95 in each cycle, equivalent to 1361.25 W/m2 CERES TSI (SORCE TSI referenced). I expected this for solar cycle #25 beforehand.
It wasn’t luck in 2022 when I predicted this cycle would likely exceed the 1.5°C ‘limit’, which it did.
Decadal warming steps happen because of an indirect solar forcing mechanism occurring in concert with direct solar irradiance forcing of the ocean upper layer, synchronized to solar cycles, that links albedo to tropical changes induced from solar minimum to maximum and back to the next minimum.
The science and exact math for this is in a paper I’m currently writing regarding the recent warming.
Although there isn’t solar data for the Holocene climate optimum, it seems likely higher solar activity was also an important climate forcing factor along with orbital forcing in creating a fairly long-enduring warmer climate that eventually changed over time into the cooler Neoglacial, cooling probably from a combination of lower orbital forcing and solar activity.
Is the TSI in the graph for 1AU or Earth distance?
TSI at 1AU varies between approx. 1360-1364.
TSI at Earth distance varies between approx. 1310-1410.
I believe the solar forcing effect on ocean temperature should be measured at Earth distance?
My earlier TSI plot is 1 AU. I use TSI data in two ways. First by using CERES 1 AU TSI daily data for annual TSI changes; and secondly by using CERES EBAF-TOA gridded monthly cloud reflectance and solar irradiance data, which accounts for earth distance.
Strong sunlight caused the recent ocean warming, from TSI in combination with albedo as determined from cloud reflectance, as shown in the following graphic of ASR, absorbed solar radiation, ASR that was derived from those two properties.
Perihelion and aphelion affect TSI at Earth distance. This effect is only visible in daily Earth distance TSI.
Perihelion and aphelion move in time by about 1 day every sixty years.
Does this movement in time affect the sea temperature historically?
I don’t know anything about the cloud effect. I think water vapor and clouds balance the Earth’s temperature and prevent the Earth from getting too hot?
TSIS-1 TSI data file.
https://lasp.colorado.edu/tsis/data/
Absolute daily sea surface temperature varies throughout the year. These variations are not reflected in the daily sea surface temperature anomaly.
One variable must be the size of the sea surface (at zenith) relative to the Earth’s tilt?
Absolute daily sea surface temperature.
https://pulse.climate.copernicus.eu/
Bob Weber:
There is one FACT that you appear to be ignoring:
Every time there is a VEI4 or higher volcanic eruption, average anomalous global temperatures decrease because of their injection of dimming SO2 aerosols into the stratosphere.
Satellite measurements of the amount of SO2 aerosols injected is typically about 200 kilotons, and temperatures decrease by about 0.2 Deg. C for 14-16 months, until they settle out. and temperatures recover to pre-eruption levels, or normally somewhat higher.
Total BS, Hunga Tonga increased global temperatures for a few years and it was VEI5 or higher. Each volcanic eruption is different.
Andy May:
I was speaking of VEI4 eruptions, for which data is readily available.
UCLA –
Google AI claims both cooling and warming resulted –
Tyndall’s experience (backed up by his mountaineering observations), showed that more H2O in the atmosphere results in lower surface temperatures.
More shielding from sunlight, less sunburn. Fact.
Just think.
Semi-continents such as Canada would be almost unsurvivable for humans for most of the year in the not-so-distant past without the abundant fossil-fueled heating plant we have these days.
The whales must have all have squeaked “thank christ!” when they heard that first oil well gushing that black life-saving fluid from a hole in the ground.
(Life-saving for humans as well as whales).
Hydrocarbon based plastic has also replaced baleen in corset stays and other such uses.
Very nice Andy, well done.
Some years ago I spent considerable time and effort trying to understand whether variations in solar output had anything to do with climate change. The modern measurable variation is too small to have any discernible direct effect. The historic ‘naked eye’ observational record on solar ‘maxima’ and ‘minima’ is at best suspect.
There were then at least two theories about a possible indirect solar climate effect. One from Australia proved mathematically defective initially, plus its corrected ‘prediction’ has since been proven wrong by observation. The other, from Europe, seems plausible and is statistically coherent—but uses observational time frames too short to as yet be verified or falsified.
So unlike Andy, I do not think solar variability is a topic worth any serious consideration even as a minor contributor to whatever ‘real’ (mindful that surface temperature measurements are more than just problematic) climate change might be happening.
A robust separate general argument. We can easily qualitatively prove that ‘climate’ changes on multi-centennial (MWP and LIA) and multi-decadal (Arctic ‘Stadium Wave’) scales. Best to just admit we don’t know why. But those facts alone falsify any climate alarm based on models deliberately parameter tuned to best hindcast—which drags in the natural variation we qualitatively know exists but cannot explain.
Now there is a third indirect solar climate effect theory, mine, which I talked about earlier here, which is supported empirically over the past nine cycles, confirmed with the current solar cycle.
The combination of this aforementioned tropical albedo mechanism with irradiance change produces sufficient total ocean forcing to account for the observed temperature change, utilizing the Planetary Temperature Equation, which is based on the Stephan-Boltzmann Equation. Accumulating retained ocean heat content from solar cycle to cycle has driven the ocean’s warming trend.
It couldn’t happen without the albedo mechanism amplifying the ocean’s solar irradiance absorption.
Hi Rud,
Your opinion is shared by most people, but not by me. The direct radiative effect of solar output changes is small, but the temperature changes on Earth are much higher than calculated, as well explained by Judith Lean and Joanna Haigh (see references in the bibliography).
I do admit that “we don’t know why.” We don’t. However, the empirical evidence that solar variability affects climate (at least in the Northern Hemisphere), is very strong and should not be ignored. We do not know the physics behind it or how it works, but that does not mean it doesn’t happen.
We’ve seen a very powerful solar grand maximum in the past century, and it coincides with modern warming of ~1 deg. We saw 5 consecutive solar grand minima between 500AD and 1800AD and over a degree of cooling, that means something and it should not be brushed aside just because we do not understand how it works. We don’t even know how much to lag it.
Hi Rud, here’s something new to think about. I’ve found that climate largely repeats every 3560 years. This is easily most easily shown in Greenland data provided proxies from multiple sites aren’t combined. I found the 3560-year interval in the orbits of the Sun and Jovian planets.
If not variations in solar activity, how would you explain this result? Systemic error? Fast (sub 200-year) variations in Earth’s orbit? Variations in LOD? Other? I guess one could argue that the 3560-year repetition doesn’t exist, but it’s pretty easy to see in this data even without resorting to correlation, or other forms of statistical analysis. This is a serious question. I’m open to speculation (except CO2 as the resonant element in a time-keeping process).
Click to enlarge.
My apologies, Rud. As I read this again I realize that it sounds like I expect you to answer the questions; I don’t. I meant for the second paragraph to be addressed to everyone.
A robust argument, the AMO is always warmer during centennial lows in solar activity.
https://www.sciencedirect.com/science/article/pii/S1364682616300360
The Sun’s orbit that shifts its distance and declination with Earth and solar activity are not completely separate from each other.
Solar minimums occur when Neptune and Uranus oppose Saturn. That means the Sun’s orbit is primarily defined by just Jupiter; meaning it is almost circular and the velocity variation is small so the solar activity is low for one to three cycles depending on the alignment of Neptune and Uranus at opposition.
The last near perfect opposition was in 1649. But there were lesser alignments in opposition in 1826 and 2007. The next alignment in 2150 is not perfect either. The 2007 opposition was the reason SC24 had low activity.
The seasonal variation in solar intensity is much greater year-to-year due to the variations in Earth-Sun distance and declination than the CO2 jockeys would have you believe. And that variation is linked to some degree with the solar activity.
The JPL Horizons web site has a good solar system orbital viewer. Run it back in time till 1649 and you will observe the near perfect alignment of Neptune and Uranus in opposition to Saturn.
The attached is the image of the 1649 conjunction of Neptune and Uranus in opposition with Saturn.
It was taken from the Horizon Orbit viewer:
https://ssd.jpl.nasa.gov/tools/orbit_viewer.html
You might also consider using this solar-system simulator:
https://www.fourmilab.ch/cgi-bin/Solar
The graphics aren’t as sophisticated, but you can go much further back in time.
Which just reminds me the “Angular Momentum” idea from Theodor Lanscheidt.
Landscheidt, sorry
Climate scientists use the pre-industrial period 1850-1900 as a reference period for the Earth’s normal temperature.
Is the Little Ice Age still ongoing during the pre-industrial period?
“climate scientists” can’t seem to agree on what the “pre-industrial” is. Sometimes it is before 1750 and sometimes it is before 1850. Anyway, it is in the Little Ice Age under either definition. The western world was very industrialized by 1800AD, large scale industrialization started about 1700. The US transcontinental railroad was completed in 1869. The usual end of the Little Ice Age quoted in the literature is about 1850 +-.
You are correct in one respect, the data they use is from 1850-1900 for global temperature. They just assume that 1750-1850 is the same. More here:
https://andymaypetrophysicist.com/2024/03/15/the-holocene-climatic-optimum-and-the-pre-industrial/
Industrialization in the 18th century was primarily water powered. Steam power was mainly a 19th century phenomenon.
Estimates of British coal use in 1700 are around 2.5 million tons; at least 10 million in 1800 and up to 250 million tons in 1900.
Watt’s separate condenser was patented in 1769. By 1800, around 500 steam engines of his improved design were in use in Britain. By 1900, there were close to 10 million.
Sounds good to me. The Little Ice Age did not end until 1850, the industrial period began well before then.
“Climate scientists” can’t agree on what the optimum climate is.
Point in fact, there is no single global climate. Averaging all the micro climates provides nothing of value except more averaged numbers.
1859 is when the first oil well was drilled.
30 miles NW of where I was raised.
Don’t forget:
Coal mining in China began around 1000 BC.
The “Fountains of Pitch” in Hit, Iraq began to be used 4000 BCE.
Oil seeps in the Zagros Mountains of Iran were used for fuel in temples 6000 BC.
Egyptians and Greeks traded bitumen 3900 BC.
Mickey Mann shows the warming starting around 1900.
So using the1850-1900 period is the absolute COLDEST during the LIA.
Except for the 2-3 prior centuries.
This is a common misunderstanding and often abused application of statistics. It is not true that the lack of correlation precludes causation. There are many situations in which one variable can drive another, but there is little or even no correlation between variables. This oft cited phrase (or similar variations) is based on assumptions that are so constraining that it doesn’t often apply especially in complex non-linear systems.
It’s easy to falsify the hypothesis that a lack of correlation precludes causation with a trivial example. y = sin(x): In this case the correlation is R^2 = 0 for a sufficiently large range of x, but changes in y are indisputably caused by changes in x.
A practical or real world example would be TSI and UAH TLT. In that case R^2 = 0.02. A person who blindly follows the mantra might see this near 0 correlation and mistakenly conclude that TSI has no causative effect on atmospheric temperatures.
There are countless other examples both theoretical and practical that could be discussed. In the interest of brevity I present but one of each.
The point is that the mantra above is narrowly confined to physical systems that 1) behave linearly, 2) have no feedback loops, and 3) have no other factors that act opposite of the independent factor being analyzed. The climate system violates all of these constraints so even the qualification “normally precludes” does not apply.
I’m not saying your thesis here is misapplying the concept of correlation. In fact, I think you’ve done quite well to avoid hinting to your audience that correlation and causation is anything other than tricky, complex, and often not obvious with the statement “Climate change is a complex combination of the Milankovitch cycles, solar cycles, and (maybe) anthropogenic factors. It does not have just one cause at any time scale.”
I bring this up because it worthy of discussion, because I often see commenters here making statements equivalent to “the lack of correlation implies the lack of causation”, and because it is relevant to when analyzing past temperatures and trying to deduce causation using correlation.
TSI is NOT the most important part of solar energy..
The ABSORBED solar radiation is what is important, and it has been climbing.
I just put a post to bdgwx about this. You are correct.
The underlying assumption, but rarely explicitly stated, is that when talking about correlation, what is meant is the relative change between two first-order (linear) variables. The mathematics doesn’t work for trigonometric functions nor even for exponential functions without transforming.
The “driving” you are referring to implies that the independent variable (x) has a range that isn’t bounded by an amplitude as with a sine or cosine or a repeating interval. For a trigonometric function that repeats indefinitely, one can demonstrate a correlation by plotting all data with the same phase (sine Pi/2 to sine 3Pi/2 or some similar segment that is ascending or descending. In other words, using a time for a periodic function instead of the trigonometric angle is inappropriate for demonstrating correlation.
It is why periodic time steps may imply correlation, but will never provide a direct relationship. Similar behavior in time may be driven by entirely different mechanisms. One may surmise a that a similar driver is causing both, but further study is required to find the solution.
Glad to see that you have learned what a functional relationship between physical quantities is. It also applies to time vs temperature. That is a time series, not a functional relationship. Can you show us a functional relationship for CO2 vs global air temperature.
Actually TSI is not a direct cause of most atmospheric temperature. A small percent of TSI is absorbed by the atmosphere. TSI is a direct cause of surface warming, that is land and oceans. The land and ocean surfaces then warm the atmosphere vis conduction, convection, and radiation. Climate science will never discover a functional relationship without including all the processes and their connections that are driven by energy from the sun.
My proof?
Look closely. Maximum insolation occurs at 12:29 pm. Maximum temperature occurs at 3:39 pm, three hours later. That time lag can vary considerably. From 1.5 to 3 hours. TSI is not the primary driver of atmospheric temperature. There are other processes occuring. I have only begun to examine soil temperatures. There is a lag there also. I suspect diffusion (conduction) to deeper soil levels screws around with the actual surface temperature slowing it temperature rise.
Here is an important question. Why does climate science never discuss this? Why are gradients never calculated for intermediate processes and combined into a coherent system?
I see more of this type of research touted here on WUWT than I ever do in peer reviewed papers that concentrate on time series of temperature which will never show a direct causation.
Is there any change in air pressure during the day?
Is there any change in air pressure during the day?
Honestly, it is always changing, some days more than others. It depends on what low/high pressure systems are moving around.
Here is a shot from today.
Increasing air pressure increases the temperature (ideal gas law).
Is it increasing air pressure that causes the temperature to rise during the day?
Pressure changes are a small but noticeable part temperature change. Going from 29.85 mmHg to 30.15 mmHg at 298K results in about a 2°C difference. That means if the diurnal change is about 10°C then a pressure change could be about 20%. Makes you think about attribution?
Does this mean that 20% of the heat energy stored in the atmosphere during the day is stored in air pressure?
When the sun sets, the air pressure decreases and the stored heat energy in the air pressure disappear?
When the sun sets, the air pressure in the atmosphere decreases and the water vapor in the atmosphere falls to the ground and forms dew?
Remember, this is for an isolated system where all the variables can be constant except for pressure and temperature. A cubic meter of air at the surface is never isolated. You can read about the Gay-Lusac experiments that allowed the derivation. You will see lots and lots of assumptions and experimental requirements to acheive the results. Conditions that in free air are just not realizable.
Excellent points, bdgwx, and I would also add that weak causal relations between a system input and its output might not result in detectable correlation if there are many other factors which also affect the output.
But I do have a quibble about this bit:
“The point is that the mantra above is narrowly confined to physical systems that… 2) have no feedback loops…”
That’s too broad. There are few physical systems which have NO feedback loops, but having feedback loops does not necessarily invalidate “the mantra above,” except is certain cases. Modest feedbacks, or even very strong feedbacks, if they’re negative and/or roughly linear, do not prevent causation from resulting in correlation.
For example, consider the relationship between the temperature of an electric stove and the average voltage applied to its resistive heating element.
The relation is obviously causal: the higher the voltage applied, the higher the temperature (with a brief delay). Yet there are several very strong negative feedbacks at work (two of which also apply to Earth’s climate system).
The first and most obvious feedback loop in that example is the Stefan-Boltzmann relation: E = ε⋅σ⋅T⁴. As stovetop temperature rises, radiative cooling, E, increases proportionate to the 4th power of temperature, T. That is a very strong negative feedback. (In climate systems we call it “Planck feedback.”)
A second feedback loop in that example is convective cooling. As the stovetop temperature rises, convective cooling of the stovetop accelerates, roughly proportionally. (In climate systems we call this “convective cooling feedback.”)
A third feedback loop in that example is the effect of temperature on resistance in nichrome heating elements: as the temperature of the wire rises, the resistance goes up, which reduces current flow and heating effect.
There may also be feedbacks with humans “in the loop.” For instance, when the stovetop gets hot it may cause the chef to dial back the stove setting, or put a skillet on the stovetop, either of which would affect the stovetop temperature.
Yet, despite all those feedbacks, it’s nevertheless still true that causation between voltage and temperature generally results in correlation. (If that causation is absent, it probably means your stove is broken!)
In general, unless feedbacks are highly nonlinear, or so strong that they cause large oscillation or overshoot responses, or both positive and so strong that they cause “tipping points” (which is very unusual), feedbacks do not invalidate the “mantra” that causation results in correlation, so a lack of correlation suggests a lack of causation.
Yes! A functional physical relationship implies correlation in the variables. It may be positive (direct relation), negative (inverse relation), or neither (a constant). Your relationship of V=IR, is an example. The variables have a physical connection.
Unfortunately feedback is another of those terms that is conflated and abused.
Feedback is, in systems engineering, a control loop term.
The output of a system feeds energy back to sum with the energy input.
I would only change this.
The output of a system feeds energy back to sum “±” with the energy input.
“The output of a system feeds energy back to sum “±” with the energy input.”
Correct. Bad assumption on my part that readers would know sums can include plus and minus.
Yeah, only engineers have to learn about this. /sarc
No, it isn’t.
That is nonsense.
Any water warmed by sunlight becomes less dense (being warmer). Less dense water floats, and moves towards the surface, displacing cooler water, which sinks.
Any water on the surface at night, will radiate towards the colder outer space. This mechanism results in the densest water being on the bottom, and the least dense on the surface.
Heat is not “stored” in the oceans. Here’s one definition of heat –
Anything (water included) that is hotter than its environment will cool, radiating energy in accordance with known physical laws at a greater rate than energy being absorbed. “Climate scientists” must be thinking of heat as a fluid, as the natural philosophers of the late 18th century believed. Caloric theory proved to be wrong.
if you have any experimental support for your speculation that heat from the Sun can be “stored” in water, I would be surprised. As Fourier said, the Earth loses all the heat it receives from the Sun to outer space, plus a little internal heat. If you have any other explanation for the Earth’s surface no longer being molten, please let me know.
Climate is the statistics of weather observations, nothing more, nothing less. Weather changes continuously, being the outcome of chaotic atmospheric processes. Nobody can predict weather better than a reasonably intelligent 12 year old – regardless of how many billion dollar computers running AI are involved.
Are the following statements true?
More solar radiation creates warmer oceans.
Less solar radiation creates cooler oceans.
More water vapor evaporates from warmer oceans.
Less water vapor evaporates from colder oceans.
More water vapor in the atmosphere creates more clouds.
Less water vapor in the atmosphere creates fewer clouds.
Burl Henry:
All Correct!
Here is a useful site: tropicaltidbits.com/analysis/ocean/
Genuine question – why is internal energy (enthalpy) not heat?
Technically, heat only exists when thermal energy is being transferred from one body to another, but the phrase “Heat Transfer” is commonly used, which is redundant. In common English “heat” is often used to mean “thermal energy.”
So, enthalpy is commonly called heat content or thermal energy content, but in reality, thermal energy is just one component of enthalpy. The other components are the PV energy and the phase dependent energy (energy to condense the water vapor etc.).
I used to use the phrase thermal energy a lot because it is technically correct, but it confused people, so I switch to the colloquial “heat.” I sacrificed precision for clarity.
You “sacrificed precision for clarity”?
Are you applying for a position as a climate scientist? (humor intended)
I guess I am! But seriously, I’m trying to write clearly and accurately. It is so common to call thermal energy “heat,” I thought it would be OK. The difference is pretty subtle and in the context of this post not very important.
Andy, I was just trying to get a smile.
Michael, Would you agree that during a La Nina, thermal energy (aka “heat”) is stored in the Pacific Ocean and during an El Nino some of the stored energy is released into the atmosphere? On a longer time scale the same is true for the AMO.
One of the confusions arises from Specific Heat Capacity, which defines the joules required to raise the temperature 1C.
Heat is conflated with energy, temperature, IR, and is basically whatever whoever cares to have it mean.
The scientific definition is the rate of thermal energy flow via molecular kinetic interactions across a temperature gradient.
And of course through a vacuum, with no “molecular kinetic interactions” at all.<g>
All energy is transferred by radiation, at the base level. Many scientists, not just “climate scientists”, don’t seem to accept reality (or maybe they just regurgitated their texts without understanding the subject).
The Wikipedia article on the “double slit experiment” contains a lot of diversionary waffle, but at least says –
albeit somewhat grudgingly.
Sorry to be so wordy, but sometimes apparently complicated things can be explained simply, and sometimes apparently simple observations just are – and cannot be explained at all!
No it is not. Does the collision of two pool balls transfer kinetic energy through radiation?. Do two molecules attempting to occupy the same space transfer kinetic energy by “radiation”?
Yes it is. Why are you asking silly questions? Why would two molecules attempt to occupy the same space? Fermions obey the Pauli exclusion principle, photons do not.
Feynman stated that all physical processes in the universe, apart from nuclear processes and gravity, can be explained by three actions –
This seems fair to me. Experiment validates Feynman’s statements.
No mention of billiard balls or molecules. Photons and electrons. Radiation. That’s it.
I suppose radiation pressure keeps basketballs and tires inflated, right?
Read this university level instruction. A1LectureNotes.pdf
Right.
I stopped when the author said –
Why ignore facts? Worried that he doesn’t understand quantum physics well enough to teach facts rather than simplified “lies for children”? Good enough for people who believe that adding CO2 to air makes thermometers hotter, I suppose.
Did you read what the paper starts with?
Why didn’t you answer my question?
Give us a quantum mechanics reference that describes how radiation keeps your tire inflated. Remember, you are the one that said;
Hi Andy, these are really great posts. A very interesting and long overdue analysis. I think most authors avoid the Holocene because there are no easy answers. But I disagree with “Climate change is a complex combination of the Milankovitch cycles, solar cycles, and (maybe) anthropogenic factors.” The last major climate change – the last deglaciation – happened concurrently, globally and rapidly between 17-14 ka, and cannot be attributed to any of these three (Broecker & Denton, 1989). And if it was anybody other than Broecker you might be able to dismiss his ideas. B&D concluded that “Quaternary glacial cycles were dominated by abrupt reorganizations of the ocean-atmosphere [climate] system driven by orbitally induced changes“, but somewhat paradoxically also claim “the rapidity, near synchroneity [sic], and global extent of the events associated with the termination of the last glacial cycle cannot be explained by the conventional Milankovitch-ice sheet link”, that is they conclude that classic Milankovitch theory cannot explain deglaciations. And they also demonstrate it couldn’t have been due to CO2 changes. We’re missing something important.
Broecker & Denton suffer along with the rest of us from lack of early Holocene solar data.
The big thing people have missed in our time is the cumulative solar cycle warming/cooling effect.
Very good points. I agree, especially with your last point:
We do not completely understand how the dominant glaciation/deglaciation cycle works. I see how the Younger Dryas ended and the Holocene began, with regard to the Milankovitch Cycles, but when you go farther back in time it gets a lot more complicated.
Javier Vinos discusses the issues and a partial solution here:
https://judithcurry.com/2016/10/24/nature-unbound-i-the-glacial-cycle/
Obviously trending downwards.
“….the only outside forces left are the Sun and greenhouse gases (GHGs).”
Really?
What about geothermal ocean heating…..as contended by Joe Bastardi?
Possibly, but the data we have says this is very minor.
From here:
https://andymaypetrophysicist.com/2022/08/16/the-sun-climate-effect-the-winter-gatekeeper-hypothesis-iii-meridional-transport-the-most-fundamental-climate-variable/
Thanks for this.
I guess with all the possible sources of heat, what really makes the difference is the amount of anomalous heat coming from various sources.
Bastardi claims of course, that there has been more stress on the ocean floor in recent decades, which in turn has been the cause of more geothermal energy coming from the oceans.
Also, how is geothermal energy from the ocean floor measured? Surely, this is a bit of an unknown – there must be a fairly large potential error in the estimates.
Bastardi might well be backed up by Fourier, who said that the Earth loses all the heat it receives from the sun to outer space, plus a little internal heat.
This is borne out by observation. Temperature rises during the day, and falls during the night. The Earth’s surface is no longer molten, having gradually cooled over the past four and half billion years, in spite of having received four and a half billion years of continuous energy from the sun!
The oceans are warmed from beneath, as are ice caps.
How is geothermal energy measured? Apart from direct observation of glowing magma observed at mid-ocean ridges,
Once again, Fourier’s name bobs up! Actually Fourier, Lord Kelvin, and many others based estimates of the age of the Earth on measurements of heat flow through the crust. Unfortunately, these estimates were doomed to fail for a number of reasons – radiogenic heat was unknown, composition and structure of the interior was unknown, and so on.
Basic physics. Anything hotter than its surroundings cools.
Neutral1966:
Bastardi is wrong. It has never been observed..
The actual control knob for our climate is simply changing levels of SO2 aerosol pollution atmosphere, a simple fact beyond the ability of most posters on this site to understand.
“Likewise, the 4.2 ka (thousand years ago) climate event does not correlate with the SGM before it or the SGMx after it, it must have other causes..”
That was definitely a Grand Solar Minimum, starting around 2225 BC, it accelerated the expansion of the Sahara. Two centennial minimums later from around 2000 BC was another GSM, which caused regional aridity and population migrations.
“The spectacular 1177BC Bronze Age collapse (Cline, 2014) follows the 70-year SGM at 1385BC by almost 200 years, so it is unclear how much influence it might have had on that climate catastrophe. The Bronze Age collapse of eastern Mediterranean civilization led to the Greek Dark Age, and it did not end until the Roman Warm Period (RWP) began around 300BC, (some place the beginning later around 250BC). The RWP does not end until 400-500AD.”
There was a 4 solar cycle GSM from 1365 BC which saw some decline, then a 5 solar cycle GSM from 1250-1195 BC. 1177 BC would likely have been a critical year weather wise, but the collapse was ongoing over decades, it didn’t all happen in one year.
The Western Roman Empire begins to decline from around 350 AD, during the GSM which caused the Early Antique Little Ice Age.
Grand Solar Minima series return on average every 863 years (+/-20yrs), as from 2225 BC, 1365 BC, 500 BC, 350 AD, 1215 AD, the next series is from around 2095 AD.
Usoskin does not list an SGM at 2225BC, the nearest are at 1385BC and 2450BC. He does have a grand solar maximum at 2065BC.
He also does not list an SGM at 1250 to 1195BC.
When the Roman Empire’s decline began is a subject of great debate, perhaps as early as the rule of Commodus around 190AD. The actual fall is clearer, that was 476AD.
I’ve seen no clear cycle of SGMs, I’m not sure why they appear when they do.
My findings on the ordering of solar cycles and their variability show exactly why centennial minima vary in length over an 863 year cycle.
The GSM from 2225 BC and from 1250 BC produced two of the most notable aridity events of the Holocene. The Usoskin data is not very useful if it failed to capture them.
I’m curious, how does the Neoglacial Period relate to current climate trends? 🤔