Author: Kirby Schlatter
Is there a periodicity in ancient climate?
Does the following climate model (Figure 6) represent a real climate cycle that repeats every 675 million years? If so, could the galactic spiral structure and its accompanying cosmic radiation be the culprit? Is the spiral structure of the Milky Way “stable” such that we encounter the same spiral arms and inter-arm regions over and over again as we orbit the Milky Way's gravitational center?
climate change story The concept of atmospheric ionization based on the formation of aerosols and clouds induced by high-energy cosmic rays. This causes the Earth to warm or cool. This cloud albedo effect (Svensmark) is the first part of the story on climate change (https://thestoryofclimatechange.substack.com). Galactic cosmic rays (mainly high-energy protons) play a central role in this process, ionizing atmospheric gases as they descend into the lower troposphere. Radio observations of exo galaxies have shown that cosmic rays are polarized in the plane of the galaxy and are localized in the spiral arm structure. This means that the cosmic ray flux will be modulated as our solar system passes through the spiral arms of the Milky Way. High flux levels during arm crossings result in cloudy and cooler climates, whereas lower flux levels during inter-arm space crossings result in less cloudy and warmer climates. We might call these geological icehouse and hothouse periods. The galactic orbit of our planetary system is circular but oscillates in-plane and out-of-plane, exhibiting secondary high-frequency cosmic ray flux modulation. This resulted in a 30 million year periodic warming-then-cooling cycle (Veizer, Shaviv). These overlapping drivers can be visualized in my 675-million-year climate cycle, based on a billion-year mosaic of Veizer and Halverson isotope proxies (Part 1, https://thestoryofclimatechange.substack.com/p/the-story-of -climate-change-part-0fd ).
what does that mean?
As our solar system continues to orbit the galactic center, we seem to encounter the same spiral arms and inter-arm regions again and again. If this process affects climate, it should reveal the cyclic nature of paleoclimate. Assuming that the nearly 13 billion-year-old Milky Way structure is generally stable, at least since the birth of our system – about 5 billion years ago – we will continue to repeat the same patterns and periodicities of climate conditions well into the distant future. From our perspective, the Milky Way's spiral arms are spinning, but at a slightly different rate than other stars in the disk, such as the Sun. From the Sun's perspective, we appear to be at rest while the galactic structures move past us and slowly recede in our wake. It is estimated that our system orbits the galactic center approximately every 225 million years. Our story suggests that our three galactic orbits will result in a complete spiral transit – once every 675 million years.
How does this pattern of stars, dust, gas, and energy persist if objects in a galaxy move along their unique orbital paths with their unique orbital periods? Is this “spiral” an illusion or does this phenomenon have a physical explanation? Why are cosmic rays mainly concentrated in the spiral arm structure and not in the inter-spiral arm region? Do the spiral arms actually exist discretely as rotating resident gravity waves, or are they a function of rotating density waves propagating through the stellar disk, constantly updating their inventory of spiral arm stellar masses? This is a mystery to me and the second part of the climate change story. However, we do live in a metaphorical world. We do a lot of things and think about a lot of ideas because we believe the statement that carbon dioxide is a climate driver is true. We can play in that game too. Should we assume that the climate change story is also true? Beautiful stories may not be entirely true, but they can inspire us to venture beyond the ordinary—and now is when the real fun begins.
Let’s imagine…
Let's imagine the near future, say 10,000 to 20,000 years from now. I think we might assume that humans will remain the dominant species on Earth, just as they have been since we left Mother Africa some 70,000 years ago. Should we consider the future climate landscape if anthropogenic carbon dioxide forces the planet into a new greenhouse environment that is 5 to 10 degrees Celsius warmer than today? Can you imagine that in 10,000 years our climate will be similar to the greenhouse Cretaceous period about 75 million years ago? Dinosaur climate. Will we see polar ice caps, sea levels 300 to 600 feet higher than today, carbon dioxide concentrations as high as 2,000 parts per million (5 times higher than today), and Antarctic forests? If we do go into a greenhouse, how long will it last? Will the greenhouse end on its own? However, the true patterns and periodicity of paleoclimate change do not appear to be well explained by cycles of weathering, subduction, and volcanism throughout Earth's geological history
Of course, we won't be forced into a new greenhouse. Remember, the greenhouse is represented by the space travel between the arms of our galaxy's orbit. Our planet will remain within the cold Sagittarius Arm for about 120 million years, causing the climate to become darker and cooler. In cloudy and cool climates, we will remain in the plane within this arm for another 2 to 3 million years. Milankovitch's planetary orbital period could then show its influence by driving the climate to oscillate between cold glacial expansions and warm interglacial periods.
Where are we now? First, we are exactly in the same plane as the Milky Way and experience the greatest cosmic radiation and the greatest potential for aerosol and cloud formation. We have been in the Pleistocene Ice Age for about 3 million years. We are in the middle of the last 20,000-year interglacial period. Ten thousand years from now, just 300 generations later, we will be at the lowest planetary tilt and slip into the next 80,000-year period of glacial expansion. Just a few hundred years after the glaciers formed, high latitudes would become uninhabitable as sea ice expanded massively onto the continents in the form of glaciers. As the ice expands, it makes our planet's albedo more reflective—returning more sunlight into space, further cooling the object. This is the ice albedo feedback in action. Runaway ice albedo processes are thought to explain the Snowball Earth scenario of the glaciation 640 million years ago. In 600 generations, 20,000 years from now, we will be in the frigid depths of an expanding ice age. About 100,000 years ago, when both inclination and eccentricity became higher, the Milankovitch cycle would resonate, providing more sunlight to high latitudes. This breaks the ice albedo feedback loop, reversing ice expansion and initiating the next warm interglacial period.
Over the next 3 million years, as the planetary system's out-of-plane orbital motion reduces cosmic radiation, cloud cover will decrease, causing temperatures to rise. This Pleistocene ice age would eventually dissipate, leaving behind these glacial-interglacial oscillations for the time being. What goes up must come down. In about 15 million years we will reach our maximum out-of-plane position, accompanied by the warmest temperatures. Our star system once again returns to the galactic plane, cooling the Earth. In 30 million years, as we travel deeper into the Sagittarius spiral arm, we will once again receive the highest cosmic ray fluxes entirely in-plane, resulting in more ionization and the greatest tendency for cooling clouds and glaciers to return. This will mark the beginning of the next ice age. Because our climate is cyclical, past climates will repeat themselves—the Marino Ice Age of 640 million years ago will repeat itself.
The big wheel keeps turning
In about 120 million years, we will finally cross the Sagittarius spiral arm. We will leave this igloo with periodic ice ages, enter the space between the next greenhouse spiral arms, and enter the next spiral arm area – the Perseus Arm. We go round and round.
With this knowledge and climate foresight about a cooling, freezing world, what do we do? It's hard to imagine, but we could organize this superorganism we call humanity and implement a plan to adapt to the coming cold snap. Albedo modifications, space-based sunglasses driving away continents and sea ice termini, and increases in carbon dioxide emissions may not be enough to be powerful climate weapons against Mother Nature. But maybe then, climate alarmists will warn us of the real problem. However, humans are notoriously short-sighted—like the proverbial frog in a slowly freezing pond—and before we know it, the brutal physics of the cold finally catch up with us.
Relevant
