It's difficult to get the precision needed to answer this question, but we have certainly had numerous extremely rapid heating events it the past. These [1] are the ice core data for the past 450k years and there were at least two major heating/cooling events that dwarf even where we're at today both hitting upwards of 10 degrees net change (from coldest to hottest) over extremely short periods of time. Interspersed in between are countless little peaks and valleys of temperatures as well, all over extremely significant temperature differences.
You really think adding in a few hundred million years of extra data about the Precambrian period (assuming we have any) is going to add value to his chart or this conversation?
No humans were even alive during this period. We don't know if human life or modern civilization is compatible with this very different environment.
Pointing out that the earth used to be warmer (which we know it has been before in the very distant past) may make people feel better about global warming, but that's the only benefit I can think of. The downside is that it makes it easier for people to postpone the needed action to fix the climate and fails to address the anticipated economic and human lethal consequences of climate change.
You don't have to go anywhere near that far back. Humanity (as in the species of modern humans) has already lived through quite extreme changes in temperatures. These [1] are data from ice core collections over the past 450k years.
Something that surprises me is that people don't seem to understand that the planet constantly goes in and out of heating and cooling phases for reasons that are still not all that well understood on a clear causal level. This in no way means that we are not contributing, potentially substantially, to the current heating phase. But it does mean that sometime right about now, even if humans did not exist, we'd expect to still see temperatures rapidly rising.
That little comic starts at ~20k years ago is at the exact end of the last ice age and the beginning of the current heating phase so it paints a very misleading picture if you were not aware of the trends before it -- which rather resemble a sin wave of temperatures. For instance humans already lived through the heating phase about 140k years ago where temperatures from bottom to top increased on the order of about 10 degrees celsius. And that was at a time when we had extremely minimal technological capacity to adapt and migrations were something that could take on the order of centuries.
And out of curiosity can anybody explain why they're downvoting this as fast they can? So far as I can tell I've said literally nothing that is not factually correct (unlike the post I was responding to). In many ways these conversations feel like people want to freak themselves out, and interspersing facts is met with hostility. I'd really like any sort of rational explanation.
I agree with all of your points, but I'm less interested in whether we can survive as a species and more interested in whether or not we can sustain and continue to improve upon our current level of societal sophistication. I'd rather we didn't regress to basic aggrarianism or worse.
The argument about natural variation is pretty well known and trotted out as a talking point on climate change. It is an appeal to normality that suggests we should just accept the condition of the earth and give up any agency.
Didn't downvote, but your premise that people don't understand that there are heating/cooling cycles is not really a thing for anyone even minutely interested in this area of study.
In fact, here's a very detailed page describing those cycles and why it appears we are deviating from the natural order.
Tangential to the topic, but your assumption there is very wrong. Due to the politicization of the topic and the media reporting, which is frequently equally sensationalistic and inaccurate, many people are extremely interested in climate change yet also know practically nothing about it. Some know less than nothing, again thanks to the media. For instance the recent report about the oceans warming even 60% than thought turns out to be wrong. The paper had a fundamental mathematical error that was detected just hours after publication by a skeptical reader. The authors' new method of measuring the warming there remains, yet now their warming figures are no different than what has already been normally reported. [1][2][3] Many media sites have run articles trying to correct their mistaken reporting, but due to the nature of social media the sensational headline gets shared a billion times, the correct indicating it was unjustified gets shared a few dozen times. So you now end up with individual basing their worldview on false facts, which is rather less than productive.
> Humanity (as in the species of modern humans) has already lived through quite extreme changes in temperatures.
That's a disingenuous argument. I can regularly survive changes of temperature between 0 deg Celsius and 30 deg Celsius, but give me one between 30 deg Celsius and 60 deg Celsius and I'd die.
Heating and cooling periods, true. CO2 in the atmosphere? Unprecedented. Why does the record above not go further back? Because that's the earliest we can reach with the ice core records. Scientists think that the earliest we've had comparable CO2 levels was the Middle Miocene. If we're going to have Middle Miocene again, we're going to have to go through a period of terrible food insecurity and societal collapse, alongside mass failure of many biospheres.
> But it does mean that sometime right about now, even if humans did not exist, we'd expect to still see temperatures rapidly rising.
Except that we know that changes in average temperature on Earth were, before the industrial revolution, almost entirely (>>90% correlation) due to cycles in solar insolation [1]. Now, that insolation accounts for less than half of the rising temperatures, meaning the energy is getting trapped in the atmosphere more and more.
It's nearly impossible to measure insolation from millions or billions of years ago like this paper did for 1600s onwards but all other related indicators, including those ice cores, are screaming that this is unprecedented. It wasn't until humanity came into the picture that indicators for solar insolation and temperature change began to diverge.
Okay, so if the planet has done it on its own before, who are we to think we can stop it? Are we gods to command the sea and tides?
On a slightly less melodramatic note, it takes a massive amount of hubris to think that we can do anything to the rock we live on that will affect it in any meaningful way. The worst thing we can do is set our civilization back a couple hundred years.
Earth has been through several mass extinction events and life keeps coming back, we are only the current stage. There is nothing we can do to change the course nature has set.
The context is people in this thread claim current climate change is happening at a historically unprecedented rate. However, supposedly a comet struck our planet and wiped out most large animals. That would presumably be a global climate change that happened really quickly, probably more quickly than anything we can do. If so, it is false to say current climate change is historically unprecedented.
Sure if you want to be pedantic about it there have (probably) been a few years in the geological record with higher deltaT's than what is currently being experienced due to volcanoes, comets, and etc. I'm sure someone else might want to debate what qualifies as 'climate' in climate change.
My point: the implication of your statement is that the former is irrelevant to us [modern humanity] because the more extreme latter has occurred previously - which is a logical non-sequitur.
it probably takes a lot of hubris to think anyone can possibly overfish the oceans. but here we are. if you have any doubts about it, ask literally anyone who's been in the industry for a few decades.
humanity is headed for very bad things in the next couple hundred years. unfortunately capitalism [and investment-fueled perpetual growth] doesnt see much further than a human lifetime and externalities seem rather inconsequential at those time scales.
Your train of logic is flawed in that the rate of change is crazy fast (https://xkcd.com/1732/). Also, since all the science is pointing to the fact the we are causing it, why shouldn't we think that we can fix it? I don't think it's outlandish at all to try to fix something caused by us.
Um, it's only hubris if it's wrong (and evidence suggests we _can_, so this argument is irrelevant). And what's hubris for a single person is not hubris for a global civilization. And it's clearly _not_ an act of hubris to think we can have _some_ outsized effects on the world around us (say, nuclear bombs affecting weather global weather patterns in measurable ways). And it's only hubris to think that because we can do this that we _should_.
These claims of humanity's hubris are wishful self-denial but they have no grounding in any kind of logic besides an emotional need to retreat from responsibility.
Yes. We are, actually. It doesn't even need to take a coordinated international political effort. The only thing stopping those with the imagination is the ethical question over whether doing it is right and proper. And maybe a few million dollars for materials and processing.
We probably can't extinct all life on the planet, but we can certainly kill off all the interesting species. Your fatalism does not absolve you of your share of the blame if it happens.
Terraforming is a nascent science, with broad potential, and we actually have the opportunity to test it out on its namesake.
This is a nonsensical straw man. People have died from lung cancer before me, does that mean I should continue a pack a day smoking habit?
Your premise is built on humans being some passive observer to planetary changes. We’re not. Look at any historical records regarding CO2 and temperature. The volumes we have emitted in the past couple hundred years is significant and measurable. The fact that this has happened for different causes in the past does not excuse humans doing the same. After all, it is we who will suffer.
That is true, however one argument that can be made is that most of life on earth was nowhere near as smart as humans are and didn't have, for example HVAC. You could make the argument that humans' intelligence will outweigh nature's attempts to wipe us out.
Of course, that doesn't mean that global warming isn't a massive problem, and HVAC won't save us. It's just important to consider all sides of an argument.
Edit: To be clear I disagree with this argument, it's just the most common one I've heard.
"Humans will try hard to survive", while undoubtedly true, isn't really a counter-argument.
As a counter to your "humans are smart" theory, I would point out that we've known about climate change for half a century now and have done absolutely nothing about it: each year we are putting more CO2 into the atmosphere than the year before. We are accelerating into the apocalypse. If humans were smart as you suppose, wouldn't we have done something other than jam our feet on the accelerator?
I respectfully suggest you examine the onset of the Eemian, the last interglacial period, about 130k years ago. Global temperature abruptly rose by more than 5 degrees Celsius in just a few centuries. That was not the most sudden warming we know of, and its speed was not a tiny fraction of the current warming speed.
A few months ago it was speculated that if Earth had seen industrial civilizations before, we would be none the wiser. While this isn't saying that would be the cause, it does give one pause.
> When it comes to direct evidence of an industrial civilization—things like cities, factories, and roads—the geologic record doesn’t go back past what’s called the Quaternary period 2.6 million years ago.
What a nonsense argument, unless they managed to build an industrial civilization without iron (https://en.wikipedia.org/wiki/Banded_iron_formation). It would be glaringly obvious if these ores had already been mined.
Maybe, but stuff tends to erode and shift a lot over millions of years, possibly smoothing over evidence to a degree where we wouldn't be able to recognize it today... on Earth. However, AFAIK the moon is fairly stable, so if there were prior civilizations, they would have to have been far less advanced than we are. Otherwise they would have surely left evidence of their existence on the moon.
Being that animals did not even appear until about 600 million years ago, It's quite unlikely industrial beings evolved before that. And any industrial civilization after 600m would leave sufficient fossils/evidence. If there were civilization before 600m, it would likely have to be aliens.
What evidence of us will exist in 600 million years? Some of the combusion products of engines are distinct as I understand it, perhaps some materials are stable that long (and if so, they could pose large pollution problems)?
I'm sure there's plenty of junk in landfills that will make for interesting fossils. The material doesn't have to be "stable", it just has to make an imprint. Most existing fossils don't comprise the original material, but are rather "mineral shadows" of what was there before.
I'm no scientist, but it amazes me that people can still think with all the industry, all the forests cut down, all the cars on the road, that our planet is magical and can handle it all.
>I'm no scientist, but it amazes me that people can still think with all the industry, all the forests cut down, all the cars on the road, that our planet is magical and can handle it all.
No one really does. They just have enough accumulated conflicts of interest to accepting that fact that life is easier for them to not do so.
I think you underestimate the various causes for willful ignorance.
It is very easy for a tiny human to assume the planet is huge and little the human can do will be significant. Ask a human to imagine 100,000 people and they are already outside our capacity. To ask them to realistically imagine millions or billions over decades and, well, the behavior is undefined.
I certainly think there are a LOT of people choosing to take the easiest (short-term) belief, but I also think there are plenty of people who just can't imagine people-scale impacting world-scale.
I had a friend who made the argument that he thinks it is arrogance to assume humans can harm the global environment on the scale of climate change. I see it as arrogance to assume we CAN'T. But I don't think he's being disingenuous - he just handles the overflow error differently.
One thing that has made an impression on me is using google maps in satellite view and appropriate zoom level. Start at northern europe and go south, or western us and go east, or any similar journey. Short of the mountain ranges, it's pretty much agriculture everywhere. Entire continents. It used to be forest.
Same here; I'm awed that just about every bit of green is parceled into pixellated rectangles, punctuated by a webwork of roads and small towns at certain junctions.
It's starting to feel like a waste of time to work on anything other than this, and whatever we need to stay functional while working on this. Anyone out there working on climate/energy/carbon-removal and hiring?
The slogan "The planet has seen sudden warming before" misses a crucial point: yes, the planet has seen sudden warming before (for some value of "sudden"). But human civilization never has. Climate change is not an existential threat to the planet, nor to life, nor probably even to homo sapiens. But it is very much an existential threat to civilization. Personally, that worries me. I'm a big fan of civilization, and I don't want to see it die. But right now it's not looking good.
[UPDATE:] As anyone who has read the story will be able to tell, I wrote the above comment before reading the story. Because the full headline is "The Planet Has Seen Sudden Warming Before. It Wiped Out Almost Everything."
But I think many people will, as I did, interpolate the truncated headline as, "The earth has seen sudden warming before [and therefore there's nothing to worry about because it all worked out the last time]."
Well, yeah, but the fact of the matter is that many people don't, and this is not entirely indefensible. One must be selective about what one reads. There just aren't enough hours in the day.
You can re-interpret my original comment as being about how misleading it is to truncate the original headline if you like. The untruncated version is <80 characters so there's no excuse.
The original headline is "The Planet Has Seen Sudden Warming Before. It Wiped Out Almost Everything." The truncated version is very misleading because many people will naturally interpolate it as, "The Planet Has Seen Sudden Warming Before [and so there is nothing to worry about because everything worked out OK the last time]." The full version is only 74 characters so there's really no excuse.
It’s not about the planet, it never was the planet will be here until the sun inflates and even that might not be enough to “kill it”.
This is about humans and our ability to survive as a civilization yet alone as a species.
Climate change poses no risk to the planet or even life as we know it in general (as while there will be an extinction event, life will persist), however it poses an existential risk to our civilization.
The best hypothesis at the moment is that the Permian-Triassic mass extinction event was caused by the enormous, million-year long eruptions that formed the Siberian Traps, combined with their ignition of carbonate rocks (which were in the process of forming large coal beds). The rise in CO2 levels and global temperature was not the fundamental problem for life on Earth -- it was the complete disruption of photosynthesis both on land and in the oceans.
If you consider the scale, mechanisms, duration, and size of the Siberian Traps eruptions [1] there is no reasonable comparison with the current effects and future consequences of just the industrial rise in atmospheric CO2 levels.
Well, would you assert that the industrial rise in CO2 levels, as such, will have consequences comparable to one of the worst mass-extinction events, caused by gigantic volcanic eruptions lasting millions of years?
I hold that unlike causes have unlike effects. The Permian-Triassic extinction started with and involved many more destructive elements than merely increased CO2 and global warming. Unlike what we are experiencing today.
And the sad thing is, if it takes hundreds of millions of years to evolve an intelligent species, as far as we know there is absolutely no way we can leave a message to the ones who could presumably come after us. Even choosing a location on Earth for the message is impossible because even optimal places for life to flourish become deserts or buried under ice or rocks on those time scales.
Makes you think how small we are.
The best bet would probably be to draw a giant smiley face on the light side of the Moon - but that's assuming that a new species will have faces like ours. Maybe the "Moon rabbit" is a perfectly obvious drawing by some ancient species' standards.
81 comments
[ 3.9 ms ] story [ 103 ms ] threadhttps://xkcd.com/1732/
https://www.bas.ac.uk/data/our-data/publication/ice-cores-an...
It's not a scale of millions of years but that's pretty good.
[1] - https://upload.wikimedia.org/wikipedia/commons/f/f8/Ice_Age_...
No humans were even alive during this period. We don't know if human life or modern civilization is compatible with this very different environment.
Pointing out that the earth used to be warmer (which we know it has been before in the very distant past) may make people feel better about global warming, but that's the only benefit I can think of. The downside is that it makes it easier for people to postpone the needed action to fix the climate and fails to address the anticipated economic and human lethal consequences of climate change.
Something that surprises me is that people don't seem to understand that the planet constantly goes in and out of heating and cooling phases for reasons that are still not all that well understood on a clear causal level. This in no way means that we are not contributing, potentially substantially, to the current heating phase. But it does mean that sometime right about now, even if humans did not exist, we'd expect to still see temperatures rapidly rising.
That little comic starts at ~20k years ago is at the exact end of the last ice age and the beginning of the current heating phase so it paints a very misleading picture if you were not aware of the trends before it -- which rather resemble a sin wave of temperatures. For instance humans already lived through the heating phase about 140k years ago where temperatures from bottom to top increased on the order of about 10 degrees celsius. And that was at a time when we had extremely minimal technological capacity to adapt and migrations were something that could take on the order of centuries.
[1] - https://upload.wikimedia.org/wikipedia/commons/f/f8/Ice_Age_...
--------
And out of curiosity can anybody explain why they're downvoting this as fast they can? So far as I can tell I've said literally nothing that is not factually correct (unlike the post I was responding to). In many ways these conversations feel like people want to freak themselves out, and interspersing facts is met with hostility. I'd really like any sort of rational explanation.
In fact, here's a very detailed page describing those cycles and why it appears we are deviating from the natural order.
http://ossfoundation.us/projects/environment/global-warming/...
[1] - https://www.sandiegouniontribune.com/news/environment/sd-me-...
[2] - https://www.latimes.com/science/sciencenow/la-sci-sn-oceans-...
[3] - https://judithcurry.com/2018/11/06/a-major-problem-with-the-...
That's a disingenuous argument. I can regularly survive changes of temperature between 0 deg Celsius and 30 deg Celsius, but give me one between 30 deg Celsius and 60 deg Celsius and I'd die.
https://www.climate.gov/news-features/understanding-climate/...
Heating and cooling periods, true. CO2 in the atmosphere? Unprecedented. Why does the record above not go further back? Because that's the earliest we can reach with the ice core records. Scientists think that the earliest we've had comparable CO2 levels was the Middle Miocene. If we're going to have Middle Miocene again, we're going to have to go through a period of terrible food insecurity and societal collapse, alongside mass failure of many biospheres.
https://en.wikipedia.org/wiki/Middle_Miocene_disruption
Except that we know that changes in average temperature on Earth were, before the industrial revolution, almost entirely (>>90% correlation) due to cycles in solar insolation [1]. Now, that insolation accounts for less than half of the rising temperatures, meaning the energy is getting trapped in the atmosphere more and more.
It's nearly impossible to measure insolation from millions or billions of years ago like this paper did for 1600s onwards but all other related indicators, including those ice cores, are screaming that this is unprecedented. It wasn't until humanity came into the picture that indicators for solar insolation and temperature change began to diverge.
[1] https://agupubs.onlinelibrary.wiley.com/doi/10.1029/95GL0309...
On a slightly less melodramatic note, it takes a massive amount of hubris to think that we can do anything to the rock we live on that will affect it in any meaningful way. The worst thing we can do is set our civilization back a couple hundred years.
Earth has been through several mass extinction events and life keeps coming back, we are only the current stage. There is nothing we can do to change the course nature has set.
I think the scientific consensus is that we already have, sadly for the worse.
If you want a discussion you have to ask a real question.
My point: the implication of your statement is that the former is irrelevant to us [modern humanity] because the more extreme latter has occurred previously - which is a logical non-sequitur.
humanity is headed for very bad things in the next couple hundred years. unfortunately capitalism [and investment-fueled perpetual growth] doesnt see much further than a human lifetime and externalities seem rather inconsequential at those time scales.
I'd like to avoid that, thanks.
These claims of humanity's hubris are wishful self-denial but they have no grounding in any kind of logic besides an emotional need to retreat from responsibility.
Yes. We are, actually. It doesn't even need to take a coordinated international political effort. The only thing stopping those with the imagination is the ethical question over whether doing it is right and proper. And maybe a few million dollars for materials and processing.
We probably can't extinct all life on the planet, but we can certainly kill off all the interesting species. Your fatalism does not absolve you of your share of the blame if it happens.
Terraforming is a nascent science, with broad potential, and we actually have the opportunity to test it out on its namesake.
Your premise is built on humans being some passive observer to planetary changes. We’re not. Look at any historical records regarding CO2 and temperature. The volumes we have emitted in the past couple hundred years is significant and measurable. The fact that this has happened for different causes in the past does not excuse humans doing the same. After all, it is we who will suffer.
Of course, that doesn't mean that global warming isn't a massive problem, and HVAC won't save us. It's just important to consider all sides of an argument.
Edit: To be clear I disagree with this argument, it's just the most common one I've heard.
As a counter to your "humans are smart" theory, I would point out that we've known about climate change for half a century now and have done absolutely nothing about it: each year we are putting more CO2 into the atmosphere than the year before. We are accelerating into the apocalypse. If humans were smart as you suppose, wouldn't we have done something other than jam our feet on the accelerator?
https://www.theatlantic.com/science/archive/2018/04/are-we-e...
What a nonsense argument, unless they managed to build an industrial civilization without iron (https://en.wikipedia.org/wiki/Banded_iron_formation). It would be glaringly obvious if these ores had already been mined.
No one really does. They just have enough accumulated conflicts of interest to accepting that fact that life is easier for them to not do so.
It is very easy for a tiny human to assume the planet is huge and little the human can do will be significant. Ask a human to imagine 100,000 people and they are already outside our capacity. To ask them to realistically imagine millions or billions over decades and, well, the behavior is undefined.
I certainly think there are a LOT of people choosing to take the easiest (short-term) belief, but I also think there are plenty of people who just can't imagine people-scale impacting world-scale.
I had a friend who made the argument that he thinks it is arrogance to assume humans can harm the global environment on the scale of climate change. I see it as arrogance to assume we CAN'T. But I don't think he's being disingenuous - he just handles the overflow error differently.
http://flibe-energy.com/ http://moltexenergy.com/ http://www.elysiumindustries.com/
[UPDATE:] As anyone who has read the story will be able to tell, I wrote the above comment before reading the story. Because the full headline is "The Planet Has Seen Sudden Warming Before. It Wiped Out Almost Everything."
But I think many people will, as I did, interpolate the truncated headline as, "The earth has seen sudden warming before [and therefore there's nothing to worry about because it all worked out the last time]."
You can re-interpret my original comment as being about how misleading it is to truncate the original headline if you like. The untruncated version is <80 characters so there's no excuse.
And yet they find ample time to read/respond to many comments here.
FWIW, my original comment was about the truncated headline and not the substance of the article.
This is about humans and our ability to survive as a civilization yet alone as a species.
Climate change poses no risk to the planet or even life as we know it in general (as while there will be an extinction event, life will persist), however it poses an existential risk to our civilization.
If you consider the scale, mechanisms, duration, and size of the Siberian Traps eruptions [1] there is no reasonable comparison with the current effects and future consequences of just the industrial rise in atmospheric CO2 levels.
[1] https://en.wikipedia.org/wiki/Siberian_Traps
I hold that unlike causes have unlike effects. The Permian-Triassic extinction started with and involved many more destructive elements than merely increased CO2 and global warming. Unlike what we are experiencing today.
Makes you think how small we are.
The best bet would probably be to draw a giant smiley face on the light side of the Moon - but that's assuming that a new species will have faces like ours. Maybe the "Moon rabbit" is a perfectly obvious drawing by some ancient species' standards.