Thread: Runaway Greenhouse Effect

I've just watched a horizon episode, which appears to be scientifically sound and well conducted, the episode was called Snowball earth. Some of you may be familiar with the theory behind it.
There seems to be overwhelming geological evidence and scientific consensus in favour of a natural mechanism in place which removes Co2 from the atmosphere at an alarmingly efficient rate, and this was clearly demonstrated in earth's history, before a single plant had colonised the land.
The program suggests that 600 million years ago, thanks to volcanoes, the atmosphere contained something like 10% Co2 (as opposed to the current 0.04%) and the greenhouse effect really was significant. Without going into too much detail, the temperature was enough to unlock the earth from the grasp of a global ice age where the entire surface of the earth was covered in a thick layer of ice..

Once the ice had thawed back into liquid water, the increase in heat caused an overwhelming amount of rain due to the consiquent increase in evaporation, it was said to have rained for a hundred years. However, as rain is the cleaning agent of Co2 from the atmosphere, it became acidic as it fell and essentially locked the Co2 away as calcium carbonate crystals within the rocks of the continents, returning the atmosphere to its more stable state of atmospheric Co2 which we find ourselves in today.


10% atmospheric Co2, removed in 100 years!?

This can be summarised more concisely:

Greenhouse --> heat --> evaporation --> rain --> no more greenhouse.

No plants required. And the Greenhouse field can be any figure you like, evidently 250 times greater than what we have today, for example.

I don't see how this is consistent with the current notion of the "runaway greenhouse effect" and that we're all going to die if we don't reduce our carbon footprint by invading the 3rd world before they become industrialised or whatever it is we need to do.

In fact it seems that if we created an engine that was capable of burning the entire, very limited resources of fossil fuels on the planet within a year, and then found there was an equal amount on mars and burnt that the following year, we'd simply see a lot of rain before it all became locked up again within the rocks as calcium carbonate crystals and during the process it probably wouldn't get warmer than a few degrees.

Earth finding equilibrium when CO2 is released naturally is slightly easier than earth finding equilibrium when we continue to pump into the atmosphere metric tons of CO2 which as been buried for millions and millions of years below the ground.

It's as if you're suggesting that surface tension in water prevents it from overflowing the top of a cup, and you now wonder why the cup is overflowing when it's sitting below a running faucet... asking why isn't the surface tension enough to keep it from overflowing anymore.

Not to worry Monkey.Man, the best available data and physical property principles indicates that that largest incremental effect from human caused CO2 is likely between .6 and 1 degree C. This is based on strong indicators that the effect to date from 1650 forward is somewhere between -.1 and +.4C and the incremental impact is nearly zero after 700 ppm.

Only Climate models contradict these empirical and physical principles and we all know that programs generate only what is programmed into the computer. Climate models are little more than expert opinions expressed in mathmatical form.

Originally Posted by cypress

Not to worry Monkey.Man, the best available data and physical property principles indicates that that largest incremental effect from human caused CO2 is likely between .6 and 1 degree C. This is based on strong indicators that the effect to date from 1650 forward is somewhere between -.1 and +.4C and the incremental impact is nearly zero after 700 ppm.

Only Climate models contradict these empirical and physical principles and we all know that programs generate only what is programmed into the computer. Climate models are little more than expert opinions expressed in mathmatical form.

No kidding. Why do I even bother trying to convince others the IPCC is wrong about CO2 adding 1.66 watts per meter of radiative forcing since 1750?

You nailed it right there. After 700 ppm, there is no measurable increase in heat. CO2 is now so close to 100% opaque to the spectra is vibrates to.

Where did that older study go that shows CO2 tops out at a 15% point? Was that 15% of blocking the atmospheric window?

Originally Posted by Monkey.Man

Greenhouse --> heat --> evaporation --> rain --> no more greenhouse.

Vapour does not rain in absence of cloud condensate nuclei (CCNs). Humans work hard to suppress CCNs, both artificial and natural, as one can plainly see from space.

The snowball Earth hypothesis is, to say the least, controversial but regardless of whether the fundamental idea is right or wrong, the idea that 100 years of rainfall washed the CO2 out of the atmosphere does not seem right at all. Paul Hoffman has studied the snowball hypothesis for years and his informed opinion is:

Carbonate and silicate rock weathering would accelerate as the ice retreats, exposing a landscape of rock debris and "flour" from the grinding action of the ice. Chemical reactions would be hastened by surface warming, acidic rain and the large surface area of fresh rock available. But even with accelerated weathering rates it would take tens of thousands of years to lower the atmospheric CO2 to a steady state with the now ice-free surface.

http://www.snowballearth.org/end.html

THX, what, a geologist can't report his observations in his own field which conflicts with what climatologists say? But they can safely ignore his observations because THEY are climatologists, and don't know anything about geology or the history of the earth?

Incidentally, there are very few climatologists. Nearly everybody working in the field has a degree in some other subject, climatology has not long been offered as a subject in itself. On thr other hand, it involves effects on the climate from many sources. Physics, Chemistry, Astronomy and so on. It is a frequent tactic of the AGW crowd to discredit the people who have opinions they disagree with. This is not the way scientific debate is done.
http://www.globalwarmingsurvivalcenter.com/

I don't see how this is consistent with the current notion of the "runaway greenhouse effect" and that we're all going to die if we don't reduce our carbon footprint by invading the 3rd world before they become industrialised or whatever it is we need to do.

If you consider the isequence of events - the amount of heat and the length of time it took to melt (or sublimate) and evaporate that much ice, and the physical state of the earth toward the end of the great evaporation but before the trigger for the great rain had tripped, you may be enlightened as to what is feared from a runaway greenhouse effect.

For another thing, we don't have huge continents of ice like that, to moderate things, any more.

It is a frequent tactic of the AGW crowd to discredit the people who have opinions they disagree with.

You can hardly blame them - it's easy to do, given the silliness of the arguments involved, and the corporate think tank folks so often include personal insults and attacks with their "arguments" that getting a little skin back is almost always available as a motive.

Originally Posted by Morissmith

THX, what, a geologist can't report his observations in his own field which conflicts with what climatologists say? But they can safely ignore his observations because THEY are climatologists, and don't know anything about geology or the history of the earth?

Incidentally, there are very few climatologists. Nearly everybody working in the field has a degree in some other subject, climatology has not long been offered as a subject in itself. On thr other hand, it involves effects on the climate from many sources. Physics, Chemistry, Astronomy and so on. It is a frequent tactic of the AGW crowd to discredit the people who have opinions they disagree with. This is not the way scientific debate is done.
http://www.globalwarmingsurvivalcenter.com/

Lazareth threads are discouraged unless there is something new and substantial to add.
Thank you.
Lynx