The Planet Has Seen Sudden Warming Before
nytimes.com
nytimes.com
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_...
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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.
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...
[1] - https://upload.wikimedia.org/wikipedia/commons/f/f8/Ice_Age_...
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.
http://flibe-energy.com/ http://moltexenergy.com/ http://www.elysiumindustries.com/
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.
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.
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.
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.
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.
[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.
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?
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.
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.
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 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.
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.
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.