Righto.
Wall of text alert.
TL;DR - there are neglibible disadvantages from preparing for the adverse effects of fast climate change and significant benefits from developing energy production to replace fossil fuels - namely, fusion power. Ergo, there's no reason not to develope fusion power as fast as possible, and prepare for the worst case scenarios as well as possible.
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On to business.
Now, there's this thing called carbon cycle. In the beginning of the Earth's history (according to all histories except YEC guys), pretty much all of the carbon was freely distributed in the atmosphere. This is the pretty much fixed amount of carbon - apart from volcanic emissions which have added some of it to the cycle - and it took some time for algae to produce free oxygen into atmosphere so that relative amount of carbon in the atmosphere reduced and majority of it become bound to the cells - dead and alive - of organisms.
During the long long geological history, large parts of that carbon has remained bound in the dead cells of organisms and become fossil fuels as we know them. So that's a chunk of carbon that has been off from the cycle for quite a sizeable amount of time, and it's not exactly an irrelevant part of it either.
Now if all that carbon were to be burned and released into atmosphere as CO
2, I don't know the exact percentage of it in atmosphere and I'm unwilling to make uneducated guesses.
What I do know is that there are very little arguments for this NOT affecting the climate and thermal equilibrium of the atmosphere.
The largest single threat of this is runaway greenhouse effect which would mean that Earth-that-was could no longer sustain our numbers, or much of anything else either as the oceans would vaporize, dissolve into oxygen and hydrogen, and the hydrogen would be blown away by solar wind. That's the absolute worst case scenario.
One could argue that hey, since that block of carbon was in the atmosphere to begin with and Earth didn't turn out as another Venus, we'll be fine. However there are two flaws in this reasoning:
1. Surplus of carbon from volcanic activity during billions of years
2. Increase of Sun's radiation output.
So this possible (though hopefully unlikely) threat can't just be swept away. I don't want to make badly argumented guesses as to how possible it would be, but it can't really be disproven either so it has to remain in the list of possible outcomes of continued carbon release.
The other outcomes, even if the climate warming doesn't get into positive feedback loop akin to Venus, are not that favourable either. Change itself is a natural part of the climate and it's pretty well documented and historically accepted that there have been much warmer and colder times than present during our planet's history.
What is the problem is the very, very rapid increase of amount of carbon in active cycle caused by widespread usage of fossilized hydrocarbons which is, actually, unprecedented in the history of Earth - until now, the carbon buried in the crust of Earth has pretty much stayed there for very long time, if not virtually forever.
This means a comparatively rapid change in composition of Earth's atmosphere is occurring. At the moment, the amount carbon dioxide isn't anything unforeseen in the history of Earth (there have been times with higher CO
2 concentrations) but I think the speed of the change is.
This means that it is also possible that the speed of climate change will be unforeseen as well. It is true that we lack the data to confirm or falsify this possibility with very good certainty, but let's endeavour the results of this possibility.
On general level: Rapid climate change leaves no time to adapt to it, for either humans or other species and biosystems on the planet. This will lead to widespread extinction that will be especially hard on specialized species and long-lived species which are slow to reach fertility and have long generations (thus having longer evolutionary response time to changes).
From humanity's perspective, a rapid climate change can cause correspondingly rapid changes in weather patterns and the dreaded sea level. The problems associated with rise in sea level are obvious - there are a lot of people and infrastructure stuck on the current coastlines. Flooding of these areas would lead to large relocations and economical problems as ports would have to be re-built on new locations, large cities and their industry would be submerged, problems from this alone would be huge.
The change of weather patterns would potentially be even larger hazard. If the distributions of precipitation were to remarkably change, it would leave to even more relocations as previously fertile areas might not be fit for cultivation any more. Desertification of places like India's or China's large wheat and rice fields would be disastrous - two billion people would be on the move searching for better place to grow their food in from those areas alone. Of course, the most obvious area they might look at is Siberia. One doesn't need to be a genius to predict problems from this sort of thing, were it to happen.
So, if a fast climate change were to happen, it would be a sociological, political, economical, humanitarian disaster of unforeseen proportions and there's no denying that. There is an "if" associated to the climate change itself and its speed, but the results of it actually happening should be largely obvious.
From ecological point of view, as said, it would disrupt practically all ecosystems on Earth, eradicate almost all specialized species, put a heavy toll on biodiversity globally and generally make the nature a few notches less interesting and vivacious, for at least a couple hundred thousand or million years. Of course in long term, large scale extinction events open road for new evolutionary steps, but from our perspective this would be irrelevant - losses of nature would be losses for us.
There is hardly any way a fast change in climate could be beneficial for either humans or ecosystems in general. Speed is the problem here.
So these are the main problems associated with the possibility of a fast climate change.
No let's take a look at what we can attempt to prevent the worst from happening.
We can:
-reduce consumption of fossil fuels and other limited resources
-limit population growth
These are partially interconnected. No one wants to drop their standard of living, so either we start being more efficient or there will have to be less of us.
From the perspective of atmospheric composition, limiting the usage of fossil fuels would be the most important thing. However, the energy requirements probably can't be reduced, so research into alternative energy production must be accelerated.
And by this I mean fusion research because that's the only energy source that can offer sustainable production of sufficient energy volume to meet our demands without being unpractical or unrealistic regarding other resources (such as windmills which can't be used as baseline power due to their reliance from weather, or solar power which takes an obscene amount of area to produce enough energy to make a difference).
In fact, I can not fathom why fusion research isn't getting tons of funding from governments, since anyone with a grain of brain in their head should realize these things after thinking them through, but I dunno, maybe exploding other people to bits is considered more productive (although at the moment humanity reproduces faster than they can be offed, so despite valiant efforts it isn't even working for reducing the population).
These are the main things that can and should be done on high level to prepare for and possibly slow down the climate change. On personal level you can try and reduce residential and personal transportation energy consumption by being a bit more frugal and using public transportation or a vehicle with good fuel economy, but you can't really affect the energy consumption of heavy industry, heavy transportation and commercial sector; changes must occur on these sectors as well.
So, there's pretty much the biggest things that can be done to counter (not necessarily prevent or stop) rapid climate change.
Losses from doing these things should the sceptics be correct and climate change not occurring (in our life time):
-some amount of discomfort if you try and consume less
-funds for fusion research away from other public projects
Gains from doing these things should the sceptics be correct:
-we get the fricking fusion power. Shouldn't that be sort of number one target of energy engineering anyway?
-as a result we could limit usage of fossil fuels even if it weren't necessary for the sake of climate stability - this would reduce the amount of particle emissions (which cause a lot of deaths alone) and preserve the stores of fossil fuels for possible future needs.
Gains from doing these things (if climate change is real and as fast as feared):
-working fusion power (long live space race, long live molvania!)
-slowing down or halting rapid climate change, and in general better preparedness for it should it happen
OR, we cold just sit on the pile of coal and let the mother****er burn, infusing the atmosphere with more carbon, hoping that the climate won't change to an unfavourable direction as a result of our actions or lack thereof.
Potential losses from this, should the climate change actually happen fast:
-poor preparedness
-general mayhem (aforementioned possible threats)
-practically irrevocable loss of lots of hydrocarbons that might become useful at some point in the future
-loss of all life on Earth (extreme worst case scenario)
Potential benefits from doing this in case the sceptics are right and the climate isn't going anywhere (in our lifetime):
-compared to present? none, really, unless you count the increased information about the climate and our planet as a benefit.
So all in all, regardless of whether or not the climate change is happening or how fast or not, the benefits from trying to counteract it would be significant in the long run, whereas if we do nothing, we may go on for some time, but it is a mathematical reality that on a finite sized planet there can not be infinite amount of resources, which means at some point we'll run out of fossil fuels anyway - or rather, gathering them will consume more energy than they provide.
At that point it will be necessary to transition to other energy sources anyway, so why not prepare for it as soon as possible...
Curiously, I have never heard or seen any argument why preparing for a rapid climate change as well as possible would be a bad thing. Or in other words how research for reducing fossil fuel usage would be a bad thing.
