Back then the continents were configured rather differently. That has a huge effect on hothouse vs icehouse regime. Right now we are in a continental configuration that should be icehouse (circumpolar currents with cold deep water). If we force the climate into hothouse against its natural state what will happen?
It's very much not settled how balanced the mantle vs surface carbon cycle is. How much carbon is in MORB? Is subducted sediment actually entrained into the mantle?
A major store of CO2 is sedimentary dolomite. We did't even really understand how that formed! (Last time I checked but I'm no sedimentologist so that might have been solved.)
Speaking as a geologist your statement is dangerously naive. I'm not saying Venus and the end of all life is definite but it is the worst case scenario of a situation that we don't understand and that will soon be (maybe already is) out of our control.
>Speaking as a geologist your statement is dangerously naive.
I'm skeptical of you being a working geologist because I haven't seen any credible claims that there is any reason to believe Earth could turn into Venus. But even outside of that, scaremongering with incredibly unlikely scenarios is also dangerous and detrimental to fighting climate change, because somebody is going to call bullshit on you and will result in your and even the general credibility of climate scientists, to be diminished.
You should speak to some more Geologists then. We really don't understand the systems of our planet and we are currently sticking a big spanner into them. Many of us are more concerned than we can publish - precisely because we don't want to scaremonger.
Will the Earth definitely turn into an out of control hothouse with a Venus - like climate? Very probably not there are many differences between Earth and Venus.
Can we be sure than some positive feedback mechanism might make life as we know it untenable on Earth? I'm not sure myself and I don't think anyone can know.
"We really don't understand the systems of our planet and we are currently sticking a big spanner into them."
There's a presumption that man is somehow an unnatural creature divorced from nature here.
If only we had multiple Earths to experiment with. One without humans as a control, another with humans as we are now and a third with humanity following whatever dictates the warmist technocrats prescribe.
Hypothetically speaking, I wonder how one would measure the utility of humanity existing at all? Some environmentalists may suggest that the Earth without humanity is the "best" of them all. There is a proximity between warmists and population control advocates.
Unfortunately, we don't have that luxury. From my perspective the "spanner in the works" analogy better fits with the economic centralization & suffering the warmist dictates may cause.
I'm politically very in favour of personal liberty. Climate change being a real and causing problems is a fact at this point (we are mainly working out how big the problems will be). I wish that some liberterian politicians would start to accept that so we can get some freedom respecting solutions!
Humanity created agricultural systems. Likewise beavers modify their environment and create ecological systems. The Internet only moralizes about the former.
I'm inclined to agree that climates change. Whether the weather is wrong, correct or otherwise undesirable due to immoral actions of men seems like a separate issue. As you mentioned, we don't fully understand the systems involved. Consequently, I prefer to err on the side of humility rather than judgement.
That said, responsible forestry management and storage of carbon in the form of cut lumber has a profit incentive. For those inclined to accept the premises of global warming, this is a solution which respects freedom. Interestingly, it is downplayed and dismissed as untenable. Even further afield are environmentalists who oppose logging and propose regulations which set the stage for CO2 emitting forest fires.
I don't see climate change as a moral issue. To me it's a practical issue. Best case climate change will seriously mess up our way of life. Worst case is very bad.
I'm not sure that we can grow and store enough trees to bring CO2 levels down to non dangerous levels in time. If we could it would certainly be worth doing. Can you point me to any calculations?
Even if this specific solution isn't viable, it is an example of what we need to do to solve this problem. Fundamentally we need to scrub a huge amount of carbon out of the atmosphere as soon as possible. Everything else is just moving the deckchairs.
There's several of these if you look. I believe one outlines how much land exactly needs to be used.
I see it as a philosophical issue. For me the warmist perspective is incoherent.
A bug's lifetime is measured in weeks. He cannot see beyond the next tuft of grass. His world is few meters in diameter and inches in height. If the aforementioned beaver floods the meadow, is it "unnatural" for the bug? Does this qualify as "sticking a spanner into a natural system"? Clearly the bug would be justified in doomsaying from his perspective.
Luckily, we are not bugs. We have the ability to adapt and gain larger perspectives than just looking at the next hedge. What we don't have is an omnipotent ability to understand the complex details of nature. Thus, we are ill qualified to make statements like, "putting a spanner in the works". Who are we to say that man's activity is worse or somehow different than nature's?
There's so much doomsaying. As you admit, we don't understand the complex systems of the Earth. A warmer period might be better for us all. We don't know. If you ascribe to the apocalyptic vision it is hard to claim that controlling other's consumption habits is not a moral issue. Either they follow the advice of their betters or are complicit in manifesting the climate apocalypse.
If we start with the moral premise that men are free, then restrictions upon that become a moral issue.
Maybe I'm just a cynic, but "cui bono" provides a more coherent explanation of the warmist agenda. It also explains why solutions like tree planting are not more popular. Carbon credits issued by a supranational entity raises alarm bells for me.
>Many of us are more concerned than we can publish.
Maybe you should be a little braver? As in, let your work be actually scrutinized by your peers (isn't that what tenure is for?) instead of scaremongering anonymously and accosting others for not understanding the science you are not willing publish? Seriously, what is the public supposed to take away from that kind of statement? Especially given that the public cannot ascertain the truth value of your Earth-will-turn-to-Venus theory. Are you trying to convince the public (on this forum no less) that this is a reasonable hypothetical situation to worry about? Come on. Put it to your peers and if they agree, then sure, let's talk policy.
>Will the Earth definitely turn into an out of control hothouse with a Venus - like climate? Very probably not there are many differences between Earth and Venus.
Didn't OP say that? Didn't I say that? What is it that you're arguing? Saying that we don't understand fully how our climate works and how many of the systems that drive it works is reasonable and nobody will dispute that. But you can't just use a lack of knowledge around an low probability event to drive global policy that could potentially be disastrous in all kinds of other ways. That's all I'm saying. We have a well-defined problem of ecosystem collapse and climate change, such as it is, don't muddle the water by coming up with new hypothetical problems.
I think I get what you are saying but maybe you could reformat it in a civil way rather than berating me.
I listed some very simple examples of places where we don't understand the Earth's carbon cycle fully. No one will publish a study saying, 'Hey guys we don't understand this yet'. We know we don't! That's why we do research to chip away at the problems.
> But you can't just use a lack of knowledge around an low probability event to drive global policy that could potentially be disastrous in all kinds of other ways.
The way I think about it like this. When I do an experiment I (am supposed to) do a risk assessment. If a proceedure has a low probability of causing a huge hazard like death I should take steps to reduce the risk of that hazard occurring as much as possible. Similarly climate change has a none zero possibility of causing humans to become extinct (and a much more than none zero chance of cause society as we know it to breakdown). Shouldn't we lower that probability?
I don't want to defend the original commenter's tone, but you must understand how frustrating it is to ask for evidence and get only a confident declaration that there's secret evidence hidden where it can't be checked. We can't drive global policy based on unverifiable insinuations about what the worst case is.
1. We don't really understand how these systems work. (The evidence for that is basically a lack of evidence and the type of thing we are still working on...)
2. Certain outcomes in the system could be very very very bad.
3. We are changing part of the system massively.
4. Because of (1) we don't know what (3) will do.
I'm not alluding to any hiden knowledge here. I'm not a climate scientist. My published work is related to other parts of the Earth's carbon cycle.
I'm sure you can see why "many of us are more concerned than we can publish" could be read as alluding to secret knowledge.
The problem with the argument is, well, why doesn't this apply to everything? Massive changes happen all the time in the world, and anything could be a disaster if our only standard for "could" is lack of knowledge that it won't be. If someone said "we need to focus our global efforts on stone-faced office buildings, because humanity might go extinct if we keep building so many all-glass ones", we'd demand more than a lack of evidence.
Luckily we were able to discuss it further and clear up some of the confusion.
> The problem with the argument is, well, why doesn't this apply to everything? Massive changes happen all the time in the world, and anything could be a disaster if our only standard for "could" is lack of knowledge that it won't be. If someone said "we need to focus our global efforts on stone-faced office buildings, because humanity might go extinct if we keep building so many all-glass ones", we'd demand more than a lack of evidence.
I can't think of any comparible examples where human activity is known to be causing massive problems... Various forms of pollution maybe? But I would argue for action there too.
It's very much not settled how balanced the mantle vs surface carbon cycle is. How much carbon is in MORB? Is subducted sediment actually entrained into the mantle?
A major store of CO2 is sedimentary dolomite. We did't even really understand how that formed! (Last time I checked but I'm no sedimentologist so that might have been solved.)
Speaking as a geologist your statement is dangerously naive. I'm not saying Venus and the end of all life is definite but it is the worst case scenario of a situation that we don't understand and that will soon be (maybe already is) out of our control.