Quanta Magazine has an article, where the writer, Howard Lee, tries to argue for human generated global warming being the main problem. But he does it in a subtle way, or is it the editor, by listing all the factors he can think of and adds to most points, how CO2 is important in that particular context and with the overall idea that since humans emitting CO2 everything is now different. In this thread, we suspect that the end result will be the return of an Ice Age, and Pierre makes the point of Global Cooling in chapter 24 of the Earth Changes and the Human-Cosmic Connection, but there are other chapters of relevance too.
Since one can encounter the points the Quanta article brings up in discussions in the public, I decided to go through the list and make a few comments based on what I knew, and what I learned in Pierre's books, including the latest Cometary Encounters.
Perhaps one could begin by mentioning a few factors that the author does not mention.
The Thermohaline Circulation
Thermohaline circulation (
THC) is a part of the large-scale
ocean circulation that is driven by global
density gradients created by surface heat and freshwater
fluxes.
[1][2] The adjective
thermohaline derives from
thermo- referring to
temperature and
-haline referring to
salt content, factors which together determine the
density of sea water.
Ocean Gyres
In
oceanography, a
gyre (
/ˈdʒaɪər/) is any large system of circulating
ocean currents, particularly those involved with large
wind movements. Gyres are caused by the
Coriolis effect; planetary
vorticity, horizontal friction and vertical friction determine the circulatory patterns from the
wind stress curl (
torque).
[1]
Gyre can refer to any type of
vortex in an
atmosphere or a
sea,
[2] even one that is human-created, but it is most commonly used in terrestrial
oceanography to refer to the major
ocean systems.
The Gulf Stream is one of the above ocean gyres.
The
Gulf Stream, together with its northern extension the
North Atlantic Drift, is a warm and swift
Atlantic ocean current that originates in the
Gulf of Mexico and stretches to the tip of
Florida and follows the eastern coastlines of the United States and
Newfoundland before crossing the Atlantic Ocean as the
North Atlantic Current.
The circulation of the ocean currents, and the Gulf Stream is described in Earth Changes and the Human-Cosmic Connection in chapter 27 and 28.
The North Atlantic Current
The
North Atlantic Current (
NAC), also known as
North Atlantic Drift and
North Atlantic Sea Movement, is a powerful warm
western boundary current within the
Atlantic Ocean that extends the
Gulf Stream northeastward.
[1]
The North Atlantic Oscillation
The
North Atlantic Oscillation (
NAO) is a weather phenomenon over the North Atlantic Ocean of fluctuations in the difference of
atmospheric pressure at sea level (SLP) between the
Icelandic Low and the
Azores High. Through fluctuations in the strength of the Icelandic Low and the Azores High, it controls the strength and direction of westerly
winds and location of
storm tracks across the North Atlantic.
[1] The NAO was discovered through several studies in the late 19th and early 20th centuries.
[2] Unlike the
El Niño–Southern Oscillation phenomenon in the Pacific Ocean, the NAO is a largely atmospheric mode. It is one of the most important manifestations of climate fluctuations in the North Atlantic and surrounding humid climates.
[3]
There are of course a number of other currents in the air and in the oceans, but the above gives an idea.
The article does also not mention comets, though he does mention asteroids. However, one important difference between an
asteroid and a
comet is that the former have low-eccentric orbits mostly within the orbits of Jupiter, and near the ecliptic plane, while comets have highly eccentric orbits that go beyond, even far beyond the orbit of Jupiter. The comets then can be much more of a surprise than the asteroids, which could be detected if we just zoomed in on the space near us, or not much beyond Jupiter. The comets include the
periodic comets, with orbits less than approximately 200 years,
long-periodic comets with orbits from 200 to 1000 years. These two groups are still more or less in the ecliptic, the disc like space where the planets also orbit the Sun. After long-period comets come
near-parabolic comets, which have periods above 1000 years followed by
hyperbolic comets which however move differently making it even more complicated to keep track of them all:
Many of these comets may come from the
Oort cloud, or perhaps even have
interstellar origin. The Oort Cloud is not gravitationally attracted enough to the Sun to form into a fairly thin disk, like the inner Solar System. Thus, comets originating from the Oort Cloud can come from roughly any orientation (inclination to the ecliptic), and many even have a
retrograde orbit.
[...]
Typically comets in the Oort Cloud are thought to have roughly circular orbits around the Sun, but their orbital velocity is so slow that they may easily be
perturbed by
passing stars and the
galactic tide. Astronomers have been discovering weakly hyperbolic comets that were perturbed out of the Oort Cloud since the mid-1800s.
How Earth’s Climate Changes Naturally (and Why Things Are Different Now)
Earth’s climate has fluctuated through deep time, pushed by these 10 different causes. Here’s how each compares with modern climate change.
I'll list them and add comments. The attention of the article lists many factors that affects the climate but weighs them in favor of CO2 emission being the main issue whenever possible. Even asteroid impacts are discussed with regard to CO2, but comets are not mentioned.
One could also say that the focus is kept on climate change, over which it is assumed we have control, rather than to enter into a discussion of Earth changes, over which we have no control.
Solar Cycles
Magnitude: 0.1 to 0.3 degrees Celsius of cooling
Time frame: 30- to 160-year downturns in solar activity separated by centuries
Every 11 years, the sun’s magnetic field flips, driving an 11-year cycle of solar brightening and dimming. But the variation is small and has a negligible impact on Earth’s climate.
More significant are “grand solar minima,” decades-long periods of reduced solar activity that have occurred
25 times in the last 11,000 years. A recent example, the Maunder minimum, which occurred between 1645 and 1715, saw solar energy
drop by 0.04% to 0.08% below the modern average. Scientists long thought the Maunder minimum might have caused the “Little Ice Age,” a cool period from the 15th to the 19th century; they’ve since shown it was
too small and occurred at the wrong time to explain the cooling, which probably had more to do with volcanic activity.
Pierre explains in his new book, Cometary Encounters, in the chapter Correlation between Cometary Activity and Volcanic Activity. page 170 how weak solar activity reduces the Earth's binding force, which loosens the tectonic plates, which then are more free to move. It is this movement that leads to earthquakes and volcanic eruptions. With more movement one will have the possibility of more eruptions. See also Earth Changes and the Human-Cosmic Connection chapter 20 and some of the subsequent chapters.
Volcanic Sulfur
Magnitude: Approximately 0.6 to 2 degrees Celsius of cooling
Time frame: 1 to 20 years
In the year 539 or 540 A.D., the
Ilopango volcano in El Salvador exploded so violently that its eruption plume reached high into the stratosphere. Cold summers, drought, famine and plague devastated societies around the world.
[...]
We know the above event, but there are other options than the Volcano, though there is more than one candidate, see https://en.wikipedia.org/wiki/Extreme_weather_events_of_535–536 In particular the volcano can't explain:
"In 2009,
Dallas Abbott of
Columbia University's
Lamont–Doherty Earth Observatory in New York published evidence from Greenland
ice cores that multiple
comet impacts may have caused the haze. The spherules found in the ice might originate from terrestrial debris ejected into the atmosphere by an impact event.
[1][26]"
A comet impact or even more, does not exclude volcanic activity. See also chapter 34 in Earth Changes and the Human-Cosmic Connection as well as chapters 20, 22 and 23. If we address the sulfur in general, there is a chapter on the subject in Cometary Encounters, it may not only have volcanic origin or originate with a comet, see p. 152-159. Venus is one example, see p. 193.
Short-Term Climate Fluctuations
Magnitude: Up to 0.15 degrees Celsius
Time frame: 2 to 7 years
On top of seasonal weather patterns, there are other short-term cycles that affect rainfall and temperature. The most significant, the El Niño–Southern Oscillation, involves circulation changes in the tropical Pacific Ocean on a time frame of two to seven years that strongly influence rainfall in North America. The North Atlantic Oscillation and the Indian Ocean Dipole also produce strong regional effects. Both of these interact with the El Niño–Southern Oscillation.
Orbital Wobbles
Magnitude: Approximately 6 degrees Celsius in the last 100,000-year cycle; varies through geological time
Time frame: Regular, overlapping cycles of 23,000, 41,000, 100,000, 405,000 and 2,400,000 years
Earth’s orbit wobbles as
the sun, the moon and other planets change their relative positions. These cyclical wobbles, called
Milankovitch cycles, cause the amount of sunlight to vary at middle latitudes by up to 25% and cause the climate to oscillate. These cycles have operated throughout time, yielding the alternating layers of sediment you see in cliffs and road cuts.
During the Pleistocene epoch, which ended about 11,700 years ago, Milankovitch cycles sent the planet in and out of ice ages. When Earth’s orbit made northern summers warmer than average, vast ice sheets across North America, Europe and Asia melted; when the orbit cooled northern summers, those ice sheets grew again. Since warmer oceans dissolve less carbon dioxide, atmospheric carbon dioxide levels rose and fell in concert with these orbital wobbles, amplifying their effects.
Today Earth is approaching another minimum of northern sunlight, so without human carbon dioxide emissions we would be
heading into another ice age within the next 1,500 years or so.
[There are illustrations of:
- changes in eccentricity as a 100,000 year cycle.
- axial precession as a 26,000 year cycle
- changes in obliquity as a 41,000 year cycle]
Three kinds of wobble: Earth undergoes cyclical changes in its orbit’s shape, known as eccentricity (top); variations in the direction of the rotational axis, known as precession (middle); and variations in the angle its rotational axis is tilted with respect to the orbital plane, known as obliquity (bottom).
Above, it is interesting that he links to a paper that suggests an ice age within the next 1500 years, if it wasn't for the importance attributed to human generated CO2 emissions that will prevent this ice age. In Cometary Encounters, Pierre argues in part 1, in the chapters on "Wandering Geographic Poles" and "Location of Geographic North Pole before Impact" (p37-44) that the positions of the geographic poles are less stable than usually assumed.
Faint Young Sun
Magnitude: No net temperature effect
Time frame: Constant
Though the sun’s brightness fluctuates on shorter timescales, it
brightens overall by 0.009% per million years, and it has
brightened by 48% since the birth of the solar system 4.5 billion years ago.
[...]
These days, the alleged brightness is of less use, considering articles like
Dark days: Earth has 'dimmed' by 0.5% since 2017 and scientists aren't sure why. Next the story that CO2 is the main driver. They clearly operate on the premise that changes are slow, while ignoring any recent cataclysmic events. Both of Pierre's books have comments on CO2 if one checks the index.
Carbon Dioxide and the Weathering Thermostat
Magnitude: Counteracts other changes
Time frame: 100,000 years or longer
The
main control knob for Earth’s climate through deep time has been the level of carbon dioxide in the atmosphere, since carbon dioxide is a
long-lasting greenhouse gas that blocks heat that tries to rise off the planet.
Volcanoes, metamorphic rocks and the oxidization of carbon in eroded sediments all emit carbon dioxide into the sky, while chemical reactions with silicate minerals remove carbon dioxide and bury it as limestone.
The balance between these processes works as a thermostat, because when the climate warms, chemical reactions become more efficient at removing carbon dioxide, putting a brake on the warming. When the climate cools, reactions become less efficient, easing the cooling. Consequently, over the very long term, Earth’s climate has remained relatively stable, providing a habitable environment. In particular, average carbon dioxide levels have
declined steadily in response to solar brightening.
However, the weathering thermostat takes hundreds of thousands of years to react to changes in atmospheric carbon dioxide. Earth’s oceans can act somewhat faster to absorb and remove excess carbon, but even that takes millennia and can be overwhelmed,
leading to ocean acidification. Each year, the burning of fossil fuels emits
about 100 times more carbon dioxide than
volcanoes emit — too much too fast for oceans and weathering to neutralize it, which is why our climate is warming and our oceans are acidifying.
Plate Tectonics
Magnitude: Roughly 30 degrees Celsius over the past 500 million years
Time frame: Millions of years
The rearrangement of land masses on Earth’s crust can slowly shift the weathering thermostat to a new setting.
The planet has generally been cooling for the last 50 million years or so, as plate tectonic collisions thrust up
chemically reactive rock like basalt and volcanic ash in the warm, wet tropics, increasing the rate of reactions that draw carbon dioxide from the sky. Additionally, over the last 20 million years, the building of the Himalayas, Andes, Alps and other mountains has
more than doubled erosion rates, boosting weathering. Another contributor to the cooling trend was the drifting apart of South America and Tasmania from Antarctica 35.7 million years ago, which initiated a
new ocean current around Antarctica. This
invigorated ocean circulation and carbon dioxide–consuming plankton; Antarctica’s ice sheets subsequently grew substantially.
Earlier, in the Jurassic and Cretaceous periods, dinosaurs roamed Antarctica because
enhanced volcanic activity, in the absence of those mountain chains, sustained carbon dioxide levels around
1,000 parts per million, compared to 415 ppm today. The average temperature of this ice-free world was
5 to 9 degrees Celsius warmer than now, and sea levels were around
250 feet higher.
And now the elephant in the room, as some of the climatologists clearly do not seem to communicate well with the geologists that have done research into cometary impacts. Below is an example of how an impact is translated mainly into something about CO2.
Asteroid Impacts
Magnitude: Approximately 20 degrees Celsius of cooling followed by 5 degrees Celsius of warming (Chicxulub)
Time frame: Centuries of cooling, 100,000 years of warming (Chicxulub)
The
Earth Impact Database recognizes 190 craters with confirmed impact on Earth so far.
None had any discernable effect on Earth’s climate except for the Chicxulub impact, which vaporized part of Mexico 66 million years ago, killing off the dinosaurs. Computer modeling suggests that Chicxulub blasted enough dust and sulfur into the upper atmosphere to dim sunlight and
cool Earth by more than 20 degrees Celsius, while also
acidifying the oceans. The planet took centuries to return to its pre-impact temperature, only to warm by a further 5 degrees Celsius, due to carbon dioxide in the atmosphere from vaporized Mexican limestone.
How or whether volcanic activity in India
around the same time as the impact exacerbated the climate change and mass extinction
remains controversial.
Next
Evolutionary Changes
Magnitude: Depends on event; about 5 degrees Celsius cooling in late Ordovician (445 million years ago)
Time frame: Millions of years
Occasionally, the evolution of new kinds of life has reset Earth’s thermostat. Photosynthetic cyanobacteria that arose some 3 billion years ago, for instance, began terraforming the planet by emitting oxygen. As they proliferated,
oxygen eventually rose in the atmosphere 2.4 billion years ago, while methane and
carbon dioxide levels plummeted. This plunged Earth into a
series of “snowball” climates for 200 million years.
[...]
One question to the above model of ancient Earth is: how did the cyanobacteria "arise", not to mention more complex life forms? While CO2 may have been important, given what we know about comets, it would seem, their influence ought to be factored in as well. I also wonder if the Earth has always been in the present orbit around the Sun? Has it always been this close or this far away?
Large Igneous Provinces
Magnitude: Around 3 to 9 degrees Celsius of warming
Time frame: Hundreds of thousands of years
Continent-scale floods of lava and underground magma called large igneous provinces have ushered in many of Earth’s mass extinctions. These igneous events unleashed an arsenal of killers (including acid rain, acid fog,
mercury poisoning and
destruction of the ozone layer), while also warming the planet by dumping huge quantities of methane and carbon dioxide into the atmosphere more quickly than the weathering thermostat could handle.
In the end-Permian event 252 million years ago, which
wiped out 81% of marine species, underground magma
ignited Siberian coal, drove up atmospheric carbon dioxide to 8,000 parts per million and
raised the temperature by between 5 and 9 degrees Celsius. The more minor Paleocene-Eocene Thermal Maximum event 56 million years ago
cooked methane in North Atlantic oil deposits and funneled it into the sky, warming the planet by 5 degrees Celsius and acidifying the ocean; alligators and palms subsequently thrived on Arctic shores. Similar releases of fossil carbon deposits
happened in the end-Triassic and the
early Jurassic; global warming, ocean dead zones and ocean acidification resulted.
The above point is of volcanic nature, and the underlying causative mechanisms mentioned earlier in connection with "volcanic sulfur" should apply. In the excerpt there is mention of mercury, which also is dealt with in Cometary Encounters p. 139-141 and again p. 150.
writing about such (pseudo) events; Up like a sun - falling flat like a pancake. 
But I can’t speak for China because I am not familiar with their weather patterns and do not wish to utter things without basis.
47news.ru
