"Why did the Earth's ancient oceans disappear? " Topic

"We think of oceans as being stable and permanent. However, they move at about the same speed as your fingernails grow. Geoscientists at CEED, University of Oslo have found a novel way of mapping the Earth's ancient oceans…"
See here

link

Amicalement
Armand

Must have been warming. Of the globe. :)

Dan
For Doggerland!
TMP link

Dan,

That should be our battle cry.

FOR DOGGERLAND! DOGGERLAND FOREVER! DOGGERLAND UBER ALLES!

LOL. I love it!

VIVA DOGGERLAND!!!

Dan

Wow, the hilarity ensues!

Of greater interest is that shortly after the "Big Thwack" (the collision with Thea that created the Moon), the Earth was a waterworld with no continents or land masses. Presumably, the extra water came from sub mantle water deposits hidden after the Hadean era. What happened to all that water?

Scientists suspect that water recyles between the surface and the transitional zone of the mantle. The actual temperature of the crust, and outlines of the changing water levels are only a miniscule part of the story of water on the earth. And hardly an argument and indictment against AGW.

I'm geeking out by taking a course on the rock and mineral evolution of the Earth. I was listening to the course on my 18 hour drive to and from Fall-In.

Of course, it's hard to launch an indictment against an unproven theory.

Aliens came and stole 'em all. 'Cause it's easier to travel half-way across the galaxy to take our water than to mine their own local space for it.

Of course, it's hard to launch an indictment against an unproven theory.

Proofs only exist in mathematics. There is no proof in science. I'll let Popper explain,

"In the empirical sciences, which alone can furnish us with information about the world we live in, proofs do not occur, if we mean by 'proof' an argument which establishes once and for ever the truth of a theory."

The Open Society and Its Enemies, Karl Popper

AGW is the current best explanation to describe the observations, the same way evolution is the best theory to explain biodiversity, and plate tectonics is the best theory to explain the movement of the continents. When something better comes along, we''ll all know.

In fact, if AGW was such a very poor explanation, then we should have a lot of observations and findings that contradict it. Not only that, but these contradictory observations should be pointing towards a clearly defined alternative. The latter is a very important point. This is the conciliation of the evidence. None has been shown yet.

I don't object to the idea of global warming. What I find very disturbing is the lumping if figures for our continuing natural post-Ice Age warming period together with what mankind might be contributing to it.

In other words, what should be our Normal sea level rise rates?*. What has it been, annually, since 16,000 BCE? More importantly, what should the natural rise continue to be for the next few thousands of years?

how much of the warming and glacial melt is NOT reversible despite our best efforts, and is NOT our responsibility to control (but instead adapt to, as we have had to since the Ice Age "ended"), because it is simply part of our planet's natural and continuing warming trend?

For once I would love to see reports that read "our natural annual sea level rise should be XX, but we are possibly adding YY to that sea level rise". But that's simply not how it is being presented to the public. I view that as potentially misleading and manipulative, which hints at agendas and unified efforts to control our national and global priorities.

I hope I made sense above. I don't know how else to word it at this moment.

Dan
VIVA DOGGERLAND!
* TMP link

I don't object to the idea of global warming. What I find very disturbing is the lumping if figures for our continuing natural post-Ice Age warming period together with what mankind might be contributing to it.

You're not going to see this in the popular press any more than a nuanced discussion on the different trade-offs involved in NATO standards.

In other words, what should be our Normal sea level rise rates?*. What has it been, annually, since 16,000 BCE? More importantly, what should the natural rise continue to be for the next few thousands of years?

Judging by our location in the Milankovitch cycle, we're starting a cooling period, with a full on glaciation due in a bout 7000 years. Cooling would lower sea level as the H2O gets stuck in the snow and ice in the polar regions.

Say I wave a magic wand, and CO2 concentrations stay at 405ppm – that's Pliocene levels and we're looking at another 75 feet of sea level rise until the earth reaches long-term equilibrium in about 300 years. In other words, all of that warming is on us and our ancestors.

Lol. Seriously? The warming period that we were told in college we were still in the middle of suddenly ended, without sending out a memo, just as we are told that we are the cause of the global warming!

Does everyone agree we have now entered a cooling period? But yet everyone agrees that we are the cause of most of the warming, and that we should put all other priorities second.

Man, the head-scratching just never ends, does it? Do you see why it's so hard for some thinking people to jump in head first?

Dan
PS. On a lighter note, that's even better news than I thought. If we have really begun a new cooling period, then I guess man-made global warming is what will save us from that full-on glaciation 7000 years from now! Our gases are the only thing standing in the way of a new Ice Age. :)
VIVA DOGGERLAND!

We are currently in an inter-glacial period (warm part) during an ice age that has been going on for the past 2.588 million. Technically speaking we're still in an ice age because extensive ice sheets still exist near the poles.

As to whether we have pumped enough CO2 in the atmosphere to end the current geological period and start the Anthropocene, neither the International Commission on Stratigraphy nor the International Union of Geological Sciences has yet officially approved the term as a recognized subdivision of geological time, but the term is working it's way though various committees for adopting the term.

Does everyone agree we have now entered a cooling period? But yet everyone agrees that we are the cause of most of the warming, and that we should put all other priorities second.

Absent of human intervention? Yes. If you subtract all of the forces with human fingerprints from the climate record, the earth would be in a very moderate cooling trend and on it's way to another glaciation. However, the warming forces more than make up for it.

Man, the head-scratching just never ends, does it? Do you see why it's so hard for some thinking people to jump in head first?

It's only "hard" because some want it to be hard. Climate science has been remarkably consistent in the past years, and especially since the mid 80s. Like I've suggested before, you'll be amazed at the consistency between the first IPCC report in 1990 and the 5th IPCC that came out 2014. Most of the changes are due to tightening of error bars, and going from we might see these climate phenomina, to these climate phenomena are likely due to increased GHG concentrations, but we as of yet – can't say conclusively that they are caused by increased GHG concentrations. Considering that the 5th IPCC report was a synthesis of the best scientific scholarship prior to 2011, the field has moved on tremendously since then.

So Marty, where did all the water go? Subduction into the mantle?

And will I see you gaming on Saturday?

Do you see why it's so hard for some thinking people to jump in head first?

Sure do, Dan. But in my experience, the "thinking people" don't have a hard time with AGW or Evolution because the topic is difficult to understand (it is). The difficulty comes when the science interferes with pre-existing religious and political viewpoints and biases.

That's why the theory of evolution gets more static than the atomic theory. No ones preconceptions are being affected. Your second last sentence from your 1:49pm, Nov 16 entry proves that.

Just saw a news piece on CBS. They went to a NASA organization. That thru satellite imagery and tracking for the last 20 years. They showed a pattern of the planet is getting warmer.

I'm not a big global warming guy, but the science seemed pretty solid according to NASA.

So what does that mean ?

Well I guess:

1) The planet is getting warmer
2) Can we really do something about it ?

I'm not a NASA "Rocket Scientist" so … I'm leaving that up to those smarter than I. Which are "legion", i.e. very many and then some.

But from what I can tell, like many things. It all revolves around/comes down to money and in turn politics. 'nuff said …

I read this as mapping areas of sea floor getting subducted away. The main driver of sea level is the amount of ice at the poles.

As for water getting subducted, that's nothing new. That's how geologist think certain gold deposts are created in the bowels of mountain ranges.

That 140 to 100 million year ago range is interesting, because that's when the Pangea breakup went into overdrive.

If it subducted, we might see it come back. Or perhaps we already are.

Dan

Yes we are. The water cycle is much more complex than ground water -> surface water -> evaporation -> atmospheric water -> rainfall. Add to that traveling to the edge of the mantle and then back up to the surface.

"Add to that traveling to the edge of the mantle and then back up to the surface."

That's the water I was referring to.

Dan

I know. It's all the same water.

The water that's falling on you today may have been bounds to hydrated crystals, such as wadsleyite and ringwoodite, hundreds of millions of years ago, within the transition zone of the Earth's mantle. These crystals are all versions of magnesium silicates, each formed depending on the surrounding pressures. Scientists estimate that wadsleyite, if saturated with water, can hold up to 20 times the surface water in all the oceans, all within the mantle.

Sorry, I'm still taking a course on mineral evolution, so excuse the geeking out. Here is a good term paper that explains things in an easy to understand manner:

PDF link

Again, as Martin indicates, this cycling process is too slow and gradual to affect ocean levels. Even when one considers steam venting from the mantle out through the crust. The oceans water levels are driven by surface water conditions, namely the state of the polar ice caps.

Brontosaurus pee, I am drinking it
Old brontosaurus pee.
And the reason I am drinking it
Is very clear to me
Every drop of moisture in the atmosphere
Is older than B.C.
What was once in that old dinosaur
Will turn to pee in me.

I any of you have the chance, take a look at Rise of Continents hosted by Dr Sir Ian Stewart on BBC 2. (I saw it on Netflix Canada). If nothing else, the cinematography is very good.

Brontosaurus pee, I am drinking it………..

Yep, we all are. But the water we are drinking existed even before the Earth did. The first stars fused all their hydrogen into helium. Once the hydrogen is all gone, the helium fuses into oxygen, among other more massive elements. These first stars already existed about 200 million years after the Big Bang. Water could be as old as 10 billion years.

At any rate the cycle of water on the Earth from mantle to surface is so long that the entire history of dinosaurs could exist within a one cycle.

Martin, the first episode is on YouTube too I think.

youtu.be/FYfuI2uZLmg

Martin, the first episode is on YouTube too I think.

link

That's a different series.