Idosyncratic Isochrons, and the Cretaceous Normal Superchron

The magnetic lineations in the ocean floor were first discovered using magnetometers designed for submarine detection. These isochrons are tenets of our notion of plate tectonics, yet many isochron patterns are inexplicable by our current tectonic model.

We have previously explored The Pacific Triangle, Charybdis and the Oldest Ocean Floor, and The Ring Around Antarctica. I had occasion to be perusing the Beaufort Sea Floor recently and discovered yet another astonishing set of discordant isochrons:

The geographic North Pole is just below and to the right of the only IODP drill site at the top of the image.

The shapes of isochrons are determined by the patterns of new ocean crust formation and crystallization. The sizes of isochrons depend on both the rate of magma extrusion and the time interval between geomagnetic reversals. Realistically, the magnetic data is messy a fair amount of interpolation goes into the even spacing of isochrons. For example, it is well known that between 83 and 121 million years ago, the longest known interval without a geomagnetic reversal took place. This is known as the Cretaceous normal superchron. If you look at this interval around the globe, you will see an even spacing of isochrons. The isochrons do not represent reversals.

What we see on the floor of the Beaufort Sea is two different systems of extrusion that took place immediately before the Cretaceous superchron. To the north is a small piece of typical seafloor extrusion between transform faults. This was very slow spreading compared with the Pacific ocean floor during this period. If we zoom in and add color we see something very strange going on.

North Beqaufort Isochrons

The lightest color is 120mya ocean floor, the next lightest blue is 125mya, and so on in 5mya increments. There were multiple parallel extrusion fins, each its own miniature mid ocean ridge spreading both directions. This pattern held for 120mya, 125mya, 130mya, and less predominantly 135mya; before the transition to more rapid extrusion 140mya.

While this was going on in the North Beaufort Sea and Arctic Ocean, the South Beaufort shows its own weird extrusions roughly parallel to the North Beaufort.

In the center part of a system with more “normal” progression, there is a series of fins even more tightly packed than to the north. They are less linear, and more like individual plutons. Note the tiny sliver of 120mya to the right against the continental shelf.

There are no trenches up here to relieve the pressure.

Zooming out to where the modern spreading ridge ends unceremoniously in the Laptev Sea, we can see that this perpendicular system is discontinuous in a line of seamounts to the left that must have been a trench. This view is basically looking straight down on the North Pole.

The green to blue color contrast basically separates extrusion before and after the Cretaceous Superchron. Very little, if any, extrusion took place at the North Pole during this interval.

 

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Radiation vs the Adiabat

Amongst those who have come to realize that climate models based on radiative transfer are running too hot, there is disagreement as to whether the hot bias results from emergent complexity the radiative transfer equations have yet to include; or the irrelevance of the radiative model.

Several people, including Ned Nikolov, have impressively modeled the atmospheric profiles of the earth and other planets using only atmospheric pressure and completely ignoring radiative effects.

As discussed before, atmospheric pressure effect warming is called adiabatic warming. It literally means “without the devil”. For our purposes here, the “devil” may be thought of as radiation.

Adiabatic warming is well known in meteorology. It includes the increased surface temperatures when atmospheric pressure is high, and the warming of “Foehn” winds as they fall from higher elevation plateaus. Such winds are the root of the disastrous fire season this year in California.

Ultimately, the adiabatic effect is due to gravity.We had not found an analysis from physical first principles so we offer the following:

Note: Gordon Dressler was kind enough to point out that the diminution of gravity begins at the center of the earth rather than the surface. Accordingly, the original graphic has been replaced by the corrected one above.

 

It can be seen that gravity approximates the density and pressure profiles of the atmosphere, but that there is significant divergence between about 3 and 20 kilometers above 5 kilometers altitude. This divergence is greatest at the tropopause, 11 kilometers in the US Standard Atmosphere. about 25 kilometers and converges somewhat thereafter.

We wondered about entropy. Noting the density curve above, we find the following:

Entropy by Density

The entropy of the atmosphere (the number of ways the molecules can be rearranged without changing properties) correlates very well with atmospheric density, and very poorly with gravity.

We conclude that gravity may well be the predominant factor in the atmospheric profile, but that other factor(s) must be in play. Very likely radiation is one of these factors. Seemingly, the devil remains ensconced in the details.

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Is the Saturation of CO2 Logarithmic?

It is generally agreed by both the red and blue teams in the climate debate that the incremental effects of increasing atmospheric CO2 diminish with increasing concentration. It is often said that the reduction of effect with increasing concentration is logarithmic.

If this is the case, where we fall on the curve at ~400ppm is critical information. If we are on the steep part of the curve, additional CO2 is far more important than if we are on the long tail.

MODTRAN offers a way to evaluate the questions of whether the diminishing effect is actually logarithmic, and where on the curve we fall at 400ppm.

Logarithmic

What we did here is scale and invert MODTRAN W/m2 looking up (for downwelling) at one meter and looking down (for upwelling) from 70 km. A simple base 10 log of ppm is added for comparison. Clearly, the logarithm is a very good approximation of the energy reaching 70 km as a function of ppm. The downwelling at one meter falls off far, far more rapidly.

The data was parsed tediously by noting the values for tropical atmosphere “full bore” (with all the other variables at default values) and varying only CO2. The one meter downwelling varies in “steps” of increasing length, resulting in the increasing sparseness of the data points. Seventy kilometer upwelling shows much more subtlety with every ppm having a different value, at least up to 20 ppm, where we switched to 10ppm increments to save time.

So, is the saturation of CO2 logarithmic or not?

Yes, and no…

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The Fire Came in the Night

The deadly fires come in the night, with the swoosh of the wind. Fingers of fire, almost liquid, reaching forward just above the ground; fireballs of mistletoe sailing high in the sky; sparks flying everywhere between.

Entropy unleashed. Potential energy gone wild. Or…simply the dragon’s breath.

Who are we to comprehend this, let alone prevent it?

A hunter’s cigarette, bad hot tub wiring, a windblown tree crashing through power lines. Errors of humans, acts of God, does it matter? The same errors or acts, absent the blow torch wind, have no issue.

That wind, and the issue have visited before.

Credit Mike Hargreaves. Only details changed since 1964. Ignition near Calistoga in Napa County, transit across the Mayacamas Mountains to Santa Rosa…if a wild assed fire chief had not stolen a bulldozer and cut broad fire breaks through what would have been houses this year, the hospital would have burned in 1964. He was lucky. The blow torch wind stopped.

The New York Times did an interesting timeline map:

NYTimesMap

By 3:AM fire trucks from Berkeley and San Francisco arrived to slow the fire’s progress at the bottom of the map…and the blow torch wind slowed. Almost on cue.

Fifty-three years is over half a human lifetime, a very long time for modern cultural memory to hold.

We built plywood houses in the dragon’s breath.

 

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River of Time

I’ve been rowing the Grand Canyon for about a month. Sixteen of us were on the river for 20 days. It takes a couple days to drive there and a couple more to drive back. It takes a day to rig and much of another to unrig.

I used to write poems more often when I was younger. Much younger.

This is what I wrote on the trip:

River of Time

When I close my eyes I see the water,
Pulsing, swirling,
Chaotic to me,

When I look up between the canyon walls,
I see the sky,
Pulsing, swirling,
Water as white clouds,
Wind that presses,

The water in the sky and in the river yearns for the ocean,
From whence it came,

We have sprung from the water,
And share the yearning,
We dance the pulses and swirls in bright artifacts,

We feel the pull of the final destination,
We know the water will reclaim us,
But we have learned that the river is the arrow of time,

We must take our temporary leave,
To dance another day.

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Socrates Died for our Sins

Was Socrates a troll? Maybe. He was not a diplomat. He sought no consensus.

Still, hemlock?

Given the chance to recant or drink, he drank.

Human superstition is boundless. We are not enlightened beings.

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Barefoot Gophernating

Barefoot gophernating is one of those senseless acts of beauty.

First of all, it requires an illegal fuel-air bomb assembly a la Caddyshack. Actually, it is not illegal as a welding rig. Mine uses a standard torch handle and propane rather than the traditional acetylene as the solvent gas. Many ironworkers use propane for cutting as well. It is cheaper and has more BTU’s.

Whenever the neighbors complain, I point to my welding rig and explain that sometimes it makes a pop.

If you have ever watched a tomato plant disappear from your garden, pulled to the subterranean netherworld by these nefarious creatures, you will understand.

This sort of terrorism demands revenge.

Enter the illegal by various Torts of nuisance gophernator.  You can blow fifty feet of gopher tunnel ten feet in the air. Even if you miss the gopher, it is enormously satisfying.

It is dangerous, like many satisfying things in life. The barefoot thing is extra spice. The directions admonish you to wear sturdy shoes. It is like brazenly standing on the second step of a three step ladder that says, “This is not a step”.

Have a great Fourth of July. My fireworks will be underground.

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