Some Global Warming adherents like to say that GW will lead to a runaway greenhouse effect of a life ending magnitude. Analogies to Venus and the fact that its surface temperature is the melting point of lead will be sure to follow.
But that is impossible. The Earth can never become like Venus. All of the greenhouse gases laid down in the form of natural gas, coal, and oil was originally in the atmosphere for hundreds of millions of years. Large oil and coal deposits are fairly recent as far as Earth’s history is concerned. If we returned all this CO2 and methane to the atmosphere it could certainly lead to a runaway greenhouse effect and we could return to something like one of several points in Earth’s history where there was very little large masses of ice on the surface and it was a tropical sauna. But Venus? Its atmosphere is nearly 100 times as massive as Earth’s and something like 95% of it is CO2. Next to that, the amount of CO2 locked up in fossil fuels is a rounding error. There are additional differences between the planets – the existing biosphere, the oceans, and various geologic processes have a moderating effect. Venus has no carbon cycle and little subduction, for example.
So, burn all the fossil fuels you want. We’re not turning into Venus. Your lead is safe. If he ever comes back, this guy might be quite comfortable though.
Depends. Your OP plays dangerous games with rhetoric. You acknowledge that the comparison to Venus is an analogy. Then you move to saying that people are saying Earth is becoming “like Venus.” By the end of your post, your position is that we are not “becoming Venus.”
No, I didn’t mean to put this in GD. I am asking if there is any process which could turn the Earth into something similar to Venus. I gave reasons why I believe it can’t. I would like to use this reasoning in future conversations in both real life and on various forums. Is my reasoning correct or isn’t it?
From these graphs, it looks like the earth has a natural stability point just shy of 22 deg C. We are currently in a short lived unnaturally cold spell.
That said, most life as we now know it evolved during this cold spell. If the earth returns to its more “normal” state, either as a natural process or as a result of us forcing it along, we may very well end up in another global extinction event, and I use the word “another” here because there’s a theory that at least one major global extinction event was caused by the earth just getting too hot.
We don’t have to get to Venus to end up in a world of hurt.
Most of what you hear these days related to global warming is a huge exercise in bovine scatology. However, there are some dangers, and it’s pretty clear that the experts don’t really know how the earth really works yet.
Assuming we could burn all the fossil fuels (which is economically and technically impossible, but let’s throw that aside) I would expect it to resemble the last epoch of Earth’s history where most of the stuff wasn’t locked in the ground. To my understanding, most of the oil was formed in a few select events in the Mesozoic. And a lot of coal was laid down in the Carboniferous. So somewhere in there. That’s why I linked to that handsome critter in my OP.
So, whatever the consensus is on the temperatures of those periods I would expect would be the result of burning everything.
Your argument is inapt. Your assertion that the Earth cannot turn into Venus is irrelevant to the debate about whether we can survive the unrestrained burning of fossil fuels. Since the Earth would become uninhabitable long before it approached the conditions on Venus, anthropogenic global warming is still a valid debate, even if you prove the Earth cannot become like Venus.
Yes. Desertification. Ocean levels rising. The elimination of former bread baskets. Pollution associated with the continued mining, processing, and application of fossil fuels. The loss of topsoil by their use in modern agriculture. The elimination of melt water from vital glaciers, such as the Himayalan glacier which provides fresh water for billions of people. These are all potential problems.
But that is all very different from the Earth turning into a sister of Venus and all life melting in a worldwide holocaust.
Dude, I’m really not trying to ride you about this, and trust me, no one appreciates a good poetic turn of phrase better than I do, but you really need to decide if you want this thread to be dominated by science or by rhetoric. The Earth is already a “sister” to Venus. Compared to other planets, they are virtually identical in size, mass, and density, and they’re in adjacent orbits. And I don’t think anyone is predicting “all life melting in a worldwide holocaust,” but I’ll go ahead and assume they are and ask for the cite on it.
Fossil fuels aren’t our carbon sink. The oceans are our carbon sink.
Venus is not earth because Venus has no plate tectonics: All tectonic activity involve vocanic eruptions, which add a great deal of carbon into the atmosphere but there is no plate subduction to remove it.
And note on that diagram: coal and oil deposits contain 3300 Gigatones of carbon (3x that in the atmosphere). The deep oceans contain 38000-40000 gigatones, and marine sediments and sedimentary rocks contain 60 million-100 millio gigatones. That is the carbon that plate tectonics removes from our system and burps back up in volcanos.
If the surface temperature of Earth is 900 degrees Fahrenheit, everything is dead. There would be no oceans. No known extremophiles could live. Even if it was “only” 200 degrees most everything on the land would be dead as well. I don’t understand what would happen to the oceans but I’m sure it would be bad as well. Was it the use of “holocaust”? I apologize if this offended anyone but I suggest they become accustomed with its use to mean mass death in general and by fire or heat in particular, e.g. “nuclear holocaust.”
If I made up the claim that anyone ever said this it’d be irrelevant to the proposition at hand anyway. But you may not have looked at enough GW debates if you’re unaware of this sentiment. Or maybe I’m looking into the wrong kinds. I’m not sure if I would call it common but you see it pop up here and there and it always makes me roll my eyes. But maybe I’m wrong and I shouldn’t, hence the thread.
Such posts can be found on this very board, even, although linking to them doesn’t strike me as very appropriate. But, if you wish to see an example of it in a “mainstream” setting, take this article from Discover Magazine:
I see no reason why humanity could not survive a climate a la the Carboniferous or Upper Jurassic.
Yes, exactly. Plus there’s the question of how we’re going to increase the mass of our atmosphere by 50 or 100 times. Of course, I’d certainly be interested in how much larger we could make it and what the hypothetical effects of e.g. doubling it would be.
This thread would be a lot more interesting if you could find an example of anyone, anywhere, with any shred of credibility, who claims that Earth is going to get just as bad as Venus.
There’s the quote from Discover Magazine, then there’s this
I’m suspicious that Hawking would get the temperature of Venus wrong by 200 degrees, but the idea is certainly out there and being attributed to people with a “shred of credibility.”
As I’ve always understood it, it can and barring intelligent intervention will, as the Sun is slowing warming. IIRC Earth has about a hundred million years left before the runaway.
But not all at once. And the Sun was cooler then.
You have no idea what you are talking about. First of all, the end result of a runaway greenhouse effect IS something like Venus; that’s what the term refers to. Not a tropical planet. And the atmosphere of Venus is what you get after everything has been cooked for millions of years and photodissociation has destroyed all the water; it didn’t start out that way. First you get a world with where the oceans boil away, and a mostly water vapor atmosphere; then the Sun’s ultraviolet breaks up the water molecules ( because so much more water is so high in the air, compared to Earth ) and the hydrogen escapes. Bake a few million years and you end up with a Venusian world-desert.
Which may well be as much an effect, not a cause of the greenhouse.
Venus most likely started out much like Earth, and became what it is now later. It may well even have had primitive life. It didn’t start out an overheated ball of acid clouds.
Earth is never going to become like Venus, at least not as a consequence of carbon emissions. That’s the answer to the GQ. Of course we all know that a cataclysm only takes tens of degrees of increase, not hundreds, but OP appears to be immune to this concept.
IMHO, if the OP thinks that this is the missing puzzle piece of some brilliant argument, there’s no way GQ can help him. Let him go off and get laughed at wherever he intends to pitch this rhetorical masterpiece.
