Based on the most up to date understanding, Richard Alley explains the fascinating interplay between geologic and chemical forces and how that directly influences our atmosphere's greenhouse properties and thus controls what will thrive in Earth's biosphere.
There are so many folds within folds of complexity that a talk or two doesn't do the topic justice, so I'm going to continue focusing on Deep-time and the evolution of Earth's atmosphere. Here I present an excellent talk by Professor Alley, who earned his PhD in 1987. Since then he’s established himself as a giant in the field of ice core studies and Paleoclimatology, having written over 240 refereed scientific publications, along with countless articles, and by now probably hundreds of engaging talks sharing his ever growing understanding with the lay public.
This one was given at the National Academy of Sciences 152nd Annual Meeting and Symposium—Earths, Moons, Mars & Stars. Below the fold I include notes and post many of his slides to help you fully appreciate the Professor's story.
There are so many folds within folds of complexity that a talk or two doesn't do the topic justice, so I'm going to continue focusing on Deep-time and the evolution of Earth's atmosphere. Here I present an excellent talk by Professor Alley, who earned his PhD in 1987. Since then he’s established himself as a giant in the field of ice core studies and Paleoclimatology, having written over 240 refereed scientific publications, along with countless articles, and by now probably hundreds of engaging talks sharing his ever growing understanding with the lay public.
This one was given at the National Academy of Sciences 152nd Annual Meeting and Symposium—Earths, Moons, Mars & Stars. Below the fold I include notes and post many of his slides to help you fully appreciate the Professor's story.
National Academy of Science's member Richard Alley presents
On 4.6 Billion Years of Earth’s Climate History: The Role of CO2
Published on Jun 1, 2015
Professor Richard Alley:
“You will meet people who say, ‘we are just telling stories,’ and no we aren’t.
We actually will generate hypotheses, that lead to new measurements,
that lead to new samples, that are taken specifically for hypothesis testing.”
We actually will generate hypotheses, that lead to new measurements,
that lead to new samples, that are taken specifically for hypothesis testing.”
Dr. Alley presents the scientific process in action,
developing an internally consistent understanding:
Professor Alley begins by outlining what Paleoclimatologists are striving to learn:
Click on images for clearer viewing.
2:10 - "We have this amazing range of indicators across physics, chemistry, biology, isotopes, and more, that actually do give us a picture of how the world changed with a great amount of confidence."
3.00 - "Things that change Earth’s climate."
3:20 - "It’s a fascinating thing when the Sun changes fast the climate immediately knows when the Sun changes slow, the climate beats it, and I'll show you this stabilizer it's a fascinating thing …"
Besides the sun, other influences from space?
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A look at Cosmic Rays' impact on climate change.
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Note the Cosmic Ray Spike at 38-40 thousand years ago,
there is no discernible impact on climate.
07:50 - "You’ll notice that the climate record ignored it now this does not prove that cosmic rays are zero but the climate record ignored it. It's not a big deal.
So we actually get to this sort of fascinating thing that walking through what can change the climate we come down to the greenhouse effect fairly quickly as a big deal and now this will be a big deal as I'm going to show you, …”
08:30 - "I wish I had the time to tell you just how much cleverness is in here:"
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Faint Sun Paradox
Given dimmer sunshine (70% of today's), why wasn’t early Earth frozen?
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Atmosphere, greenhouse gases, rocks, chemical reactions,
the "Rock-Weathering Thermostat."
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Exploring a concept, long term stabilizer (slow defense) vs. the fast break.
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Map of glacial evidence for snowball Earth
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Massive lime stone deposits above glacial deposit.
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12:45 - "There are these certain special times that the Earth seems to have turned into a snowball, that might be consistent with our idea of a big slow powerful defense. Now if you make a snowball and cover the earth in ice it is very reflective it takes a long time to build up enough volcanic CO2 to make it warm again. Then that volcanic CO2 should make it really warm. We should see an immense amount of rock weathering taking CO2 down, and you should see immense amount of inorganic equivalents of shells.
So there's a prediction here which is that if this CO2 mechanism is working the end of a snowball should see huge amounts of CO2 turning to rock after making it warm and melting the snowball."
14:00 - "CO2 is a big deal in a lot of Earth's history…”
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Earth’s Thermostat and things that impact it
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15:20 - "Because of our understanding of these stabilizers, it is not the case that warmth made CO2 high, it is the case that CO2 made warmth. Because our understanding of the physics chemistry of the system gives you the direction of the arrow. This actually works pretty well and so in point of fact what you see is the thermostat being reset and the climate history looking like the CO2 history."
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Paleocene-Eocene Thermal Maximum (PETM)
Incidentally,
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18:10 - "The ice ages recently the ice ages recently are not caused by CO2 but right ok so here's here's a climate record..."
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Milankovirtch Predicted this,
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50 years later the observations confirm him.
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20:00 Global Heat and Moisture Distribution Engine in action
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20:35 - “… because the whole world changes together even though the sunshine is doing seesaws. When you ask, why is that, the only successful explanations that have ever been generated are this red curve above it (CO2) …”
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Time for a moment of reflection:
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and it really does care about almost everything, and be honest …
… the history of climate looks more like greenhouse gases than anything else and of those greenhouse gases it looks like CO2 has been the biggest control on it.
And this is an emerging picture that has come out in my career but I think we were surprised. I think we expected other things to be more important but what we see is CO2 mattering. A lot.
22:50 - Ok and the big changes of the past we could do something similar if we burn it all, only we'll do it faster than basically everything except the meteorite that killed the dinosaurs. …
People say, oh climate’s always change so we don't need to worry about changing the climate, right. I have had elected officials tell me that. The logic is fantastic, right, it is equivalent to nature's always cause fires, so we do not need to worry about arson.
It is exactly the same logic right we’ve always died so we don't need to worry about investigating murders. I'm sorry, this is sort of crazy. But when you look back (in Earth’s geology) they drew those lines where things died. And we could do things that big, and we might do them faster.
I scare students with this, and then I leave them with this one, which is the big smile - is that, we're the first generation in history that can look at each other with a straight face and say we know how to get off of this treadmill we do know how to build an energy system that will be sustainable. But the one we got isn’t."
Professor Richard Alley
PennState University
Professor Richard Alley
PennState University
{Got that Scott Pruitt???}
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To OMAK March12, 2020,
What if wishes were Leer Jets? And gravity was optional?
Then even beggars could fly.
What if you actually learned about the topic and the geophysical facts? Then you would appreciate how utterly insane William Happer's claims are!
But then, I imagine you aren't ready to discuss it in any detail, since I'll bet you know nothing of the details to begin with. No, sorry, parroting FOX headlines won't be of help if you want to discuss the actual science of manmade global warming.
Oh and if you want to debate Happer, please do come on down:
What if both Professor Alley's theory and Professor William Happer's argument on saturation effect with rising CO2 are true, which says that doubling from 400 ppm to 800 ppm will be almost negligeable ?
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