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Tom Mazanec
2017-Aug-16, 07:48 PM
Say global warming continues until all geological carbon fuel is burned and the feedbacks run around, making the tropics uninhabitable and melting all the glacial ice, and finally heating up the oceans.
IIRC, ice melt will raise sea level 60 or 70 meters.
HOWEVER, the oceans will also rise from thermal expansion of the sea water. How much will this contribute?
How long will the rise take?

Squink
2017-Aug-21, 10:54 PM
World's largest volcanic range may lurk beneath Antarctic ice (https://www.sciencedaily.com/releases/2017/08/170814092735.htm)
Does not answer your question, but it's a lovely new addition to worst case scenario.

Scientists found 91 previously unknown volcanoes, ranging in height from 100 to 3850 metres. The peaks are concentrated in a region known as the West Antarctic Rift System, spanning 3,500 kilometres from Antarctica's Ross Ice Shelf to the Antarctic Peninsula.

publiusr
2017-Aug-25, 09:57 PM
CO2, shoggoths--now this...

On a serious note--it is easy to imagine Antarctica as nothing but a flat plain with some mountains--with nothing but ice. But it is a continent--with varied terrain like any other--we just can't see it.

BigDon
2017-Aug-30, 03:42 PM
Hey Tom, here's one for you.

Don't you know that that *dropping* sea levels are also caused by global warming?

https://phys.org/news/2017-08-caspian-sea-evaporating-temperatures.html

Swift
2017-Aug-30, 05:38 PM
Hey Tom, here's one for you.

Don't you know that that *dropping* sea levels are also caused by global warming?

https://phys.org/news/2017-08-caspian-sea-evaporating-temperatures.html
First sentence from the linked article (I added the bold):

Earth's largest inland body of water has been slowly evaporating for the past two decades due to rising temperatures associated with climate change, a new study finds.

Unless the Caspian Sea is fed by melting glaciers or a melting ice cap, it seems completely unsurprising to me that if the temperature is higher, there would be more evaporation and water levels would drop.

However, the "not fed by melting glaciers or a melting ice cap" criteria would not apply globally to the oceans.

Squink
2017-Oct-30, 12:14 AM
Glacial cliffs of over 100 meters seem to collapse quickly when they hit the sea: New science suggests the ocean could rise more — and faster — than we thought (https://www.washingtonpost.com/news/energy-environment/wp/2017/10/26/new-science-suggests-the-ocean-could-rise-more-and-faster-than-we-thought/?utm_term=.02cad1430a0a)
Pretty little piece of work, and on the drowned reefs too.

Robert Tulip
2017-Nov-01, 10:35 PM
Say global warming continues until all geological carbon fuel is burned and the feedbacks run around, making the tropics uninhabitable and melting all the glacial ice, and finally heating up the oceans.
IIRC, ice melt will raise sea level 60 or 70 meters.
HOWEVER, the oceans will also rise from thermal expansion of the sea water. How much will this contribute?
How long will the rise take?

In that hypothetical event, the transfer of all carbon into the atmosphere and oceans, Jim Hansen calculated from his study of Venus at NASA that the runaway greenhouse effect would cause the sea to boil (https://www.skepticalscience.com/Venus-runaway-greenhouse-effect.htm). As a result, all the water would convert to steam, and the sea level would fall by an average of four kilometres.

The biggest immediate risk though may be a repeat of the Permian Great Dying caused by ocean stratification. https://www.earth-syst-dynam.net/8/1/2017/esd-8-1-2017.pdf states "the largest mass extinction of ocean biota within the Phanerozoic epoch, during the Permian–Triassic transition, was induced by high temperatures as a consequence of elevated CO2 levels, which induced the change from a well-mixed oxic to a stratified euxinic–anoxic ocean (Kaiho et al.,2016 (http://www.heliyon.com/article/e00137))."

Tom Mazanec
2017-Nov-05, 01:00 PM
In that hypothetical event, the transfer of all carbon into the atmosphere and oceans, Jim Hansen calculated from his study of Venus at NASA that the runaway greenhouse effect would cause the sea to boil (https://www.skepticalscience.com/Venus-runaway-greenhouse-effect.htm). As a result, all the water would convert to steam, and the sea level would fall by an average of four kilometres.

The biggest immediate risk though may be a repeat of the Permian Great Dying caused by ocean stratification. https://www.earth-syst-dynam.net/8/1/2017/esd-8-1-2017.pdf states "the largest mass extinction of ocean biota within the Phanerozoic epoch, during the Permian–Triassic transition, was induced by high temperatures as a consequence of elevated CO2 levels, which induced the change from a well-mixed oxic to a stratified euxinic–anoxic ocean (Kaiho et al.,2016 (http://www.heliyon.com/article/e00137))."

I had a very intelligent and experienced friend named Ed Langley (died Sep 2001) and I posed the "Venusification" of Earth as a possible end result of Fossil Fuel Burning. He replied "If the impossible can happen, then the impossible can occur." ie he did not believe it.
Maybe he was wrong.

Robert Tulip
2017-Nov-05, 04:01 PM
I had a very intelligent and experienced friend named Ed Langley (died Sep 2001) and I posed the "Venusification" of Earth as a possible end result of Fossil Fuel Burning. He replied "If the impossible can happen, then the impossible can occur." ie he did not believe it.
Maybe he was wrong.
Your opening post presented a hypothetical scenario of the shift of all carbon from the crust to the atmospheric system of our planet. That scenario would produce a runaway greenhouse effect.

However, it is impossible because the world economy would collapse long before such a dire result. The economic collapse would remove the ability and incentive to shift ever more carbon into the air.

Just the proven reserves of oil and gas companies were calculated (http://www.rollingstone.com/politics/news/global-warmings-terrifying-new-math-20120719) as five times more than the emission limit needed for a two degree warmer world back in 2012, so the potential damage of continued emission is high, even if your scenario is impossible.

If people work out how to mine carbon from the air then the carbon carrying capacity of the atmosphere will not be relevant to any realistic prognosis.

publiusr
2017-Nov-08, 08:36 PM
I had a very intelligent and experienced friend named Ed Langley (died Sep 2001) and I posed the "Venusification" of Earth as a possible end result of Fossil Fuel Burning. He replied "If the impossible can happen, then the impossible can occur." ie he did not believe it.
Maybe he was wrong.

I see a return to the Carboniferous, yes--but not "Venusification"

Ara Pacis
2017-Nov-15, 04:11 AM
Say global warming continues until all geological carbon fuel is burned and the feedbacks run around, making the tropics uninhabitable and melting all the glacial ice, and finally heating up the oceans.
IIRC, ice melt will raise sea level 60 or 70 meters.
HOWEVER, the oceans will also rise from thermal expansion of the sea water. How much will this contribute?
How long will the rise take?

All you really need is here (https://water.usgs.gov/edu/density.html), a list of the density of water at various temperatures. Plug your estimate into a calculator, do the math for volume of the world's oceans and you'll have the change in volume.

If you want estimates of timelines, this (https://en.wikipedia.org/wiki/Sea_level_rise#/media/File:Projected_change_in_global_sea_level_rise_if_ atmospheric_carbon_dioxide_concentrations_were_to_ either_quadruple_or_double_(NOAA_GFDL).png) is a good chart on the Sea Level Rise wikipedia article.

Keep in mind, however, that warming sea water might not circulate as well, slowing the global conveyor and increasing the time it takes to warm the deep water. This might cause the surface water to become warmer faster than one might expect. Also keep in mind that melting ice will absorb a lot of heat, reducing some of the warming in some areas.

BigDon
2017-Nov-18, 08:19 PM
No, we can't go Venus. It's not in the planetary sciences options.

The absolute worst case *real* scenario is a five to eight degree span around the equator becoming to hot for most multicellular live. With temps ranging from a low of 120F up to 140F during the day.

eburacum45
2017-Dec-08, 02:45 PM
Your opening post presented a hypothetical scenario of the shift of all carbon from the crust to the atmospheric system of our planet. Not quite that much; just all available fossil fuel. The total amount of carbon in the crust is probably hundreds of times larger than the accessible fossil fuel reserves. But we would never be able to extract all that carbon, since it is too thinly distributed and would take more energy to extract than it would yield in energy. Thinly distributed kerogen isn't useful fuel, neither is calcium carbonate.

Tom Mazanec
2017-Dec-09, 02:11 PM
Not quite that much; just all available fossil fuel. The total amount of carbon in the crust is probably hundreds of times larger than the accessible fossil fuel reserves. But we would never be able to extract all that carbon, since it is too thinly distributed and would take more energy to extract than it would yield in energy. Thinly distributed kerogen isn't useful fuel, neither is calcium carbonate.

Then the carbon would not be a "fuel". To make this more plausible and explicit, assume just the economically and energetically available carbon is burned.

Robert Tulip
2017-Dec-09, 07:27 PM
Then the carbon would not be a "fuel". To make this more plausible and explicit, assume just the economically and energetically available carbon is burned.

Bill McKibben, in his 2012 article Global Warming's Terrifying New Math (http://www.rollingstone.com/politics/news/global-warmings-terrifying-new-math-20120719), said total fossil fuel reserves accounted in stock values were five times the amount of carbon that could be added to the air to keep within two degrees of warming.

Tom Mazanec
2017-Dec-10, 03:36 AM
Bill McKibben, in his 2012 article Global Warming's Terrifying New Math (http://www.rollingstone.com/politics/news/global-warmings-terrifying-new-math-20120719), said total fossil fuel reserves accounted in stock values were five times the amount of carbon that could be added to the air to keep within two degrees of warming.

So does this mean ten degrees of warming? Or is it logarithmic?

Squink
2017-Dec-16, 03:14 AM
So does this mean ten degrees of warming? Or is it logarithmic?

Difficult to say when catastrophic things like the Clathrate gun hypothesis (https://en.wikipedia.org/wiki/Clathrate_gun_hypothesis) could easily be floating around in the system being modeled.

profloater
2017-Dec-16, 10:10 AM
the role of water means at a "tipping point" to use an overused cliche, the greenhouse effect is logarithmic because a warmer atmosphere holds more water vapour. Finding that point is complicated by the role of clouds in the current situation. Recent research on dark coloured biofilms on ice has worried modellers. Greenland for example is not pure white with ice but has significant darkening from bacteria. So sea levels may rise faster than we thought. the volumetric expansion at 10C is 88 ppm, it's zero at 4 C and rises with temperature. It reaches 700 ppm at 90 C I hope we don't get there! 100ppm is 1% so the contribution to sea rise is under 1% for the time being. (per 1 degree C