And how long is it reckoned to take? Let’s assume (and maybe we don’t have to, I dunno) the trigger has been pulled on climate change and there’s really nothing we can do about it. As I understand it, there are two immediate consequences. Ice caps & glaciers go bye-bye and coastal areas get inundated; and weather patterns change giving us problems with farming & food production. But as much as that would suck, we’re a reasonably clever species and I don’t see those issues as insurmountable.
But then there’s gotta be some secondary impacts, right? How much does the ocean have to warm up before it can’t absorb enough oxygen for the fishies? And presumably that gets compounded by algal blooms/die offs. But still…I’m reasonably confident we could work around the inconvenience of enduring a significantly different ocean as well. Problem is, a nontrivial amount of our oxygen comes from the ocean (like 50%+ right?). So the death of the ocean starts to hurt us in that respect.
What’s the timeline like for that? I guess the root of my question is: is it possible for the climate to change drastically enough to cause massive die-offs, probable societal collapse (famine, skirmishes for resources, etc.), but still be meaningfully survivable for feral humans? Or are we instead looking at a situation where we get a significantly different planet chemistry that is inhospitable to most/all life as we know it?
I think most scientists agree that the anticipated changes, while inevitable at this point, will be gradual, spanning scores if not hundreds of years. While this is a mere blink of an eye in evolutionary terms, some creatures will be able to adapt to the changes, but some won’t. For example, I have no idea if the oceanic algae will be able to adapt to the warming oceans, but a sudden and complete die off seem unlikely given the size of the earth.
Humans will have plenty of time to adapt, such as moving away from the rising coastlines, but ultimately we are tied into the web of life on earth and at some point we may be in trouble. However I believe there will always be someplace where some humans can survive… it’s a big world out there.
You’re not going to get a factual answer to this. It’s all conjectural at this point. In some cases, it’s conjecture informed by science, and in others it’s informed by politics or ignorance. But the system is too complicated to definitively say what will happen.
That said, there was research reported yesterday about the likelihood of a sixth mass extinction (and the first since the dinosaurs) within the next 250 years. We’re currently losing species at a rate of 20 to 100 times the rate of the past, and it seems to be accelerating. So for those species, the earth is unlivable already.
For humans, it depends on how you define “unlivable.” If you mean humans going extinct, that’s probably a very long while if ever. If you mean a significant percentage of the population dying, it could be 50 years, 250 years, or maybe we’ll magic our way out of it. If you simply mean people dying because of the effects of climate change, that’s happening today.
In the aggregate, not much less livable at all. However, that dismisses the geographic, weather and political issues and simply assumes people can relocate to whatever the new “nice parts” are. But the idea that earth, all of it, is going to become some unlivable hellhole is entirely wrong.
L.A. and South Beach will become unlivable hellholes, or underwater hellholes. Winnipeg, St. Petersburg and Antarctica should become quite nice.
There have been times in the past when CO2 was around half a percent, which is much much higher than it is now (.04%) or is likely to get in the next few centuries (.1% maybe) but changes happened much more gradually back then and we’re not entirely sure what the rapidity of the change will mean. I think it’s highly unlikely that Earth would become “unlivable”, but when you combine global warming with overpopulation and monoculture, it’s not hard to imagine some ecological collapse which would bring modern civilization to the ground and reduce the human population by a factor of 100. Certainly many species are going extinct but it’s not likely that Homo Sapiens will be among them, unless some biological weapon is unleashed while a few billion hungry people are fighting over who owns the dwindling arable land.
Rather than asking about doomsday scenarios, I think the real questions we should be asking ourselves are…
Q: How likely is it that AGW will continue to increase? A: extremely likely.
Q: How likely is it that AGW will cause serious political problems like increasing wars fought over resources and increasing numbers of displaced refugees? A: pretty likely.
Q: How much worse will the ongoing mass extinction be when AGW gets worse? A: not sure, but probably significantly worse.
Q: How do the benefits of AGW compare to the downsides? A: The benefits (like a longer growing season in Norther latitudes) are small compared to the large downsides (like increased droughts and storms in the Tropics).
Q: Do the benefits of mitigating AGW outweigh the costs? A: Probably yes, especially for whoever takes the lead in green technology. At the very least, conservation means lower fuel costs. But if it eases pressure on things like wars and refugees then so much the better.
It will never be “unlivable”. Humans can live in a lot of different places in a lot of different conditions. Some places will become truly unlivable - especially those that will be under water - but people can move around. The changes will be mostly economic and political. You may be living on prime real estate which your great-grandchildren will inherit as desert or seabed.
Rich nations may become poor, the poor become rich. But that’s the story of human civilization; same old, same old. There would be wealth and starvation, ups and downs, even if the climate were rock solid.
In my opinion, the real catastrophe mankind faces is not climate change but the end of cheap fossil fuels. We’ve been “eating” fossil fuels for the last hundred-plus years in the form of greater agricultural productivity. When it’s gone, a lot of us are going to starve.
The question needs a little refinement - it’s not a matter of ‘whether climate change will have an impact or not’ - it’s a matter of ‘how much will temperatures change?’
Slight climate change (say, 2°C on average over the next 100 years) is likely to cause less impact than large amounts of change (say, 6°C on average over the next 100 years.)
MIT’s Joint Program on the Science and Policy of Climate Change uses a gambling-wheel analogy to communicate the uncertainty around amount of average temperature rise.
The problems of “mitigating” global climate change are on a par with catching WTC1 halfway down and restoring it to place.
At very best… we are in for one rough century. More realistically, the next phase of human history will have to accommodate global changes larger than any in the span of wide-scale human existence.
Which is in no way an argument against doing what we can, for many reasons… but the odds of stopping climate change and significantly reversing it within the lifespan of any person now living… pretty thin.
No, mitigate means “to make less severe, serious, or painful” and/or “to lessen the gravity of.”
Mitigation of climate change can include actions like building levees to prevent inundation of low-lying areas or moving populations to more northerly areas - neither of which is as impossible as catching the collapsing skyscraper.
Maybe you thought sbunny said something else, like “preventing climate change?”
That’s how the term is usually used - “fix it so things can go back to normal” - and that’s within the general meaning of “mitigate.” Too many discussions seem to have “fix it and reverse all the problems” as an option that we could select, somehow.
If I misunderstood the intent of the post, apologies, but I think it’s an issue on which the discussion should steer as far from vague and misunderstandable concepts as possible. We’re already saddled with the ‘dragons of indecision’ - no need to make it worse by not communicating clearly.
Given the nature of this topic, I expect this to wander a bit from GQ territory, but since it is here in GQ, let’s all try to stick to factual information and leave the debatable aspects of the topic to a more appropriate forum. Let’s also try to focus a bit more on the OP, and not immediately shift into the more general topics of AGW and climate change, since there are already plenty of existing threads for those.
When I said mitigate, I meant lessen the impact. I’m well aware that “back to normal” isn’t an option. But reducing our CO2 output could make the difference between “really bad” and “kinda bad”.
During the age of the dinosaurs, CO2 was more like 1200-1600 ppm (three to four times what it is now) and the global average temperature was 10-15 degrees C higher than now (18-27 degrees F higher than now) and there was no ice at either the North or South poles. Certainly such conditions are “survivable” (especially if you’re a lizard) but if we had to make such a shift in only 100 years that would be “really bad”.
OTOH, if we can slow the rate of CO2 increase so the global temp only goes up 5 degrees C and it takes 200 years instead of 100, that would be “kinda bad.” That’s what I meant by mitigation.
In climate change literature, “**mitigation **refers to the actions taken to reduce the greenhouse gas (GHG) emissions in order to minimize their effects on global climate change (Burton, Diringer and Smith 2006). The IPCC defines mitigation as “an anthropogenic intervention to reduce the anthropogenic forcing of the climate system; it includes strategies to reduce greenhouse gas sources and emissions and enhancing greenhouse gas sinks” (IPCCC 2007).”
“**Adaptation **refers to coping with those impacts of climate change that cannot be avoided (Burton, Diringer and Smith 2006). The IPCC defines adaptation as “initiatives and measures to reduce the vulnerability of natural and human systems against actual or expected climate change effects. Various types
of adaptation exist, e.g., anticipatory and reactive, private and public, and autonomous and planned. Examples are raising river or coastal dikes, the substitution of more temperature-shock resistant plants for sensitive ones, etc.” (Boko et al. 2007).”
Emphasis added to both.
These are generalities, of course, and there are lots of actions and impacts that have both adaptive and mitigative aspects.
Boko, M., I. Niang, A. Nyong, C. Vogel, A. Githeko, M. Medany, B. Osman-Elasha, R. Tabo and P. Yanda. (2007).
“Africa. Climate Change 2007: Impacts, Adaptation and Vulnerability. Contribution of Working Group II
to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change,” M.L. Parry, O.F.
Canziani, J.P. Palutikof, P.J. van der Linden and C.E. Hanson, eds. Cambridge University Press, Cambridge,
UK, 433-467.
Burton, I., E. Diringer, and J. Smith. (2006). Adaptation to Climate Change: International Policy Options.
Arlington (VA), US: Pew Centre on Global Climate Change.
A note on one of authors of this study.The author is Paul Ehrlich. Ehrlich is also well known for kinda sorta predicting mass starvation in the U.S. and England by he 1980s. I say ‘kinda sorta’ because Ehrlich, after ’ The Population Bomb’ predictions did not come true, claimed that what he wrote (and gave numerous speeches on) weren’t really predictions.
Anything that has Ehrlichs name on it that isn’t about butterflies ought to be treated as a) purely ideological and b) wrong.
That’s a good point. In this case, I tend to believe the article’s conclusions about current extinction rates. I wouldn’t put much stock in Ehrlich’s predictions about the future.
Some stoner on the ski lift this past winter told me that it was definitely going to be 15 years from now. I’ve started buying more property in the mid-west.
Predicting what is going to happen where is impossible. I have to credit the statement that 2014 is the warmest year since records were kept. But not for us in Montreal (not to mention Boston). Two consecutive harsh winters with a very mild summer in between (and so far, this summer would appear to another mild one, at least so far). I read an explanation for this in terms of breakdown of a barrier between us and the arctic (the “polar vortex”), but I can’t say I really understood it.
Anyway, I think it will be bad, but life on earth is not in danger. We will survive but we may have blown the chance for saving civilization.
