
Paleoclimatology: Explaining the Evidence (2006) - DrScump
https://earthobservatory.nasa.gov/Features/Paleoclimatology_Evidence/
======
phkahler
My favorite reading on ice ages was the theory that the cycle all started when
a tectonic plate rose in Panama and joined north and south America. This
blocked the connection of the Atlantic and Pacific oceans which changed global
circulation patterns. If that is true, then the way to prevent another
glaciation is not to pump carbon into the atmosphere but the nuclear
excavation of Panama :-)

~~~
bradyd
> the nuclear excavation of Panama

This has been considered in the past.
[https://en.wikipedia.org/wiki/Project_Plowshare](https://en.wikipedia.org/wiki/Project_Plowshare)

~~~
phkahler
Yeah, but the idea here isn't to make a canal for ships, but to have a
significant flow between the oceans. My vague memory is that someone suggested
a channel 600 feet deep and a mile wide. I don't have a reference for this
unfortunately.

------
DrScump
(2006 paper)

Related paper from 2010:

[https://www.sciencedaily.com/releases/2010/04/100406133707.h...](https://www.sciencedaily.com/releases/2010/04/100406133707.htm)

------
posterboy
I found striking the line up of the mediteranean, the black sea and the
caspian sea, even further the aral sea and I was wondering if this line was on
the aequator before. So if it was, I would wonder, what's the significance of
this? Tidal and centrifugal forces influencing the tectonic movement and vice
versa, changing water movements influencing the rotation.

~~~
anvandare
You're right about water influencing the rotation, in a way: increasing
drought in the Indian subcontinent and Caspian Sea caused the rotational axis
to stop moving towards Hudson Bay and start moving toward the British Isles
around 2000[1]. But the Axial tilt of the Earth (and thus the "change in
latitude of the Equator") always stays within 2° of 23°.[2] So no, that line
was never on the Equator.

Those seas were formed by tectonic movement and are not (directly) related to
each other. The Caspian and Black Sea are remnants of the Parathetys Ocean[3]
while the Mediterrean is a remnant of the Tethys Ocean. The driving forces of
plate tectonics aren't completely understood yet, but the Earth's rotational
axis (probably) doesn't play a large part.

[1] [https://www.nasa.gov/feature/nasa-study-solves-two-
mysteries...](https://www.nasa.gov/feature/nasa-study-solves-two-mysteries-
about-wobbling-earth)

[2]
[https://en.wikipedia.org/wiki/Axial_tilt#Long_term](https://en.wikipedia.org/wiki/Axial_tilt#Long_term)

[2]
[https://en.wikipedia.org/wiki/Paratethys](https://en.wikipedia.org/wiki/Paratethys)

~~~
posterboy
> The driving forces of plate tectonics aren't completely understood yet, but
> the Earth's rotational axis (probably) doesn't play a large part.

that's a paradox thing to say. at least, it doesn't have to play a large part,
anyway the effect could be large and largely chaotic.

~~~
posterboy
PS: I was thinking the closing of the thetys would stop the water circulation
through it and that should have a huge effect.

What is understood about the driving force of tectonics at all, by the way?
Subcutan magma flows are important, I guess.

~~~
anvandare
I see what you mean by paradox. It's definitely chaotic in that the system
loops back on itself, but the main component of tectonics are (supposed to be)
mantle cells due to heat difference between the core and the crust.[1] There
are Euler poles (also confusingly named poles of rotation - but they're
unrelated to the axis of rotation or the poles of the Earth) involved in plate
tectonics, but for describing how they move relative to each other.[2]

[1]
[https://en.wikipedia.org/wiki/Earth%27s_internal_heat_budget](https://en.wikipedia.org/wiki/Earth%27s_internal_heat_budget)

[2]
[https://www.usna.edu/Users/oceano/pguth/md_help/geology_cour...](https://www.usna.edu/Users/oceano/pguth/md_help/geology_course/euler_poles.htm)

