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Comment by mr_overalls | Hacker News Reader

The sad thing is that scientists have understood the risks of global warming for decades, and yet our civilization (maybe I'm just speaking for the US here) seems impotent to effectively coordinate a response to this slow-motion threat.

It could be our own Great Filter.

https://en.wikipedia.org/wiki/Great_Filter

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Are there credible models that suggest Earth will turn into Venus or something? It would take a hell of a lot more to end humanity than it would take to "merely" hurt/kill the most vulnerable segments of our population (which is what I thought the stakes were).

> Are there credible models that suggest Earth will turn into Venus or something?

Yes, the model is called Venus.

> (which is what I thought the stakes were).

You were misinformed. The stakes are significantly higher than that.

Venus is a shit model for Earth. Try again.

I’m sorry, but it has long been shown Earth cannot simply turn into Venus given the current climate models.

There is definitely no shortage of doomsday climate models. CREDIBLE models is a different story.

Look back at ones from 20+ years ago to see what they predicted would be happening by now. It's pretty funny actually.

The models from 20 years ago overshot by several confidence intervals because they underestimated mixing the deep ocean. "The barrel is bigger than we expected" doesn't make the rising water in the barrel any less concerning, but it's not the triumph of foresight that you seem to imply.

Grandparent didn't imply it was a triumph of foresight, but rather a failure of foresight.

I think that's what he's saying - a general point that people's understanding of climate (and thus predictions about it) are poorer than commonly believed.

Well, one day we might realize that we underestimated some critical aspect of climate change. Having overestimated it in the past is not an argument for relaxing today, and is certainly not a laughing matter.

Are there any models that predict accurately backwards?

All of them, because that's how you build models? Or do you mean something different?

Pretty sure he ment modern models that prove to be more right than others using past data.

Interesting question imo

I mean per the other response that is how you build models like this aka yes, all of them. Source: Am a Statistician

edit: that doesn't mean they are correct going forward necessarily and most of the doomsday models I've seen are simulations that run thousands of times and a very small number of the simulations predict doom and a very small number predict no effects. The average of these expiriments is often the most likely scenario but doesn't really make headlines.

I don't need models when I have the historical record. The historical record says mean sea level is going to be hundreds of _meters_ above current levels in the not-too-distant future.

This is why people don't listen to the scientists, because absurd FUD like this gets spread and it discredits the entire movement. Even the most doomsday predictions are on the order of inches, maybe over a foot in the next 50 years. Such a rise would still be incredibly devastating, don't get me wrong, but it would take about a hundred years of a completely runaway warming cycle to raise the seas a single meter, much less hundreds.

I'm quite serious about the historical record. This is not FUD, this is data. The historical record shows that the last time atmospheric CO2 concentration was at the level we are at currently, several things were true. 1) temperatures were 4-5C higher. 2) there was no permanent surface ice anywhere on the planet as far as they can tell. 3) mean eustatic sea level was anywhere from 50 to 200m above current levels.

http://onlinelibrary.wiley.com/doi/10.1029/2008PA001615/full

Keep in mind, it's not just melting you need to figure in, there's also the thermal expansion of water.

Also models do not currently project the Antarctic losing all of its ice, yet this is what the historical record suggests is likely. The models also do not account or undercount the contribution of non-anthropogenic forcing factors such as the one this article refers to -- they assume that _we_ are the main feedback loop, and yet there is evidence that we have entered a regime where we could reduce emissions to zero and the non-anthropogenic feedback would continue to add CO2 and methane to the atmosphere at a rate equal to or exceeding our current emissions.

I believe the main reason you aren't hearing things like this is because scientists are picking their most defensible claims because they know that they will be hounded by climate change deniers. They are not talking about their worst fears, for worry of being labeled FUD.

It's not just melting and thermal expansion. There's also loss of mass at the poles, which increases sea level elsewhere.

Edit: sense

You really defended your position quite effectively, thanks for the perspective.

When I read the paragraph 55 of the article, I think that it tells a different story. Basically, it's 20-30 meters higher seas; a good part of it coming from tectonic stuff. And they also say that sea level increase appeared before warming.

The volume of the ocean basin is something that I haven’t been able to find data for one way or the other. The timeline is different — there is a lot of data and of course it doesn’t all line up perfectly. The generally accepted reference timeline, which is based on a single south Atlantic core sample, is calculated using an assumption about the annual rate of sediment deposition. There is evidence that mid ocean sediment deposition dropped during PETM while coastal deposition increased. This is likely because the oceans become inhospitable due to increasing acidity and warming caused the same thing we see today — increased evaporation rate and warmer air being able to hold more moisture as water vapor leads to increased rainfall and therefore river flows increased generally. There have been attempts to try and correct for this factor using iron deposition variability which may correlate with planetary precession and other techniques, some of which change the timeline fairly drastically at the scale we’re talking about.

Long story short — yes this is an oddity but there’s not a well accepted explanation for it and there is reason to question whether we have the PETM timeline correct for the area of interest. (the onset is quite sudden, geologically speaking, although not as sudden as the data we are producing right now!) I would encourage you to do more reading and build an opinion based on the sum of evidence rather than that one paper, which I linked to simply because it has an accessible graph for sea level variability compared to today.

wow that's an answer ! I'm out of my league :-)

> I don't need models when I have the historical record. The historical record says mean sea level is going to be hundreds of _meters_ above current levels in the not-too-distant future.

What in the historical record says this?

Edit: saw your reply to my sibling after I posted this.

http://onlinelibrary.wiley.com/doi/10.1029/2008PA001615/full

Feel free to do your own research, obviously. You are looking for eustatic sea level during PETM (Paleo-Eocene Thermal Maximum).

You will likely find a lot of studies which show coral reefs and anything that lives in the ocean and has a shell is about to have an even worse time of it than we are!

(To be clear, hundreds is the most extreme value -- the variability at different sites is fairly high, but roughly 50m is the minimum.)

No, the Earth has been a lot warmer and colder in the past. We've had massive volcanoes going off for thousands of years, we've had iceball earth, we've had crocodiles and palm trees in the arctic.

The Earth's systems always balance out over the long run. We don't stay trapped in ice ages or hot phases.

The difference is that civilization is a comparatively new development, and nobody really knows how that's going to fare in the face of all this. The human cost is likely to be staggering.

If nobody knows than why do you assume the cost _likely_ staggering?

We're uncertain about the rarity of global collapse due to climate change. The more uncertain we are about our uncertainty of the rarity of a global catastrophe, the more rational it is for us to assume we are likely presently under-estimating its rarity, rather than over-estimating it, because examples of global catastrophe are pretty hard to come by. If nobody knows if it's gonna happen, but the consequence of catastrophe is so bad that it disrupts life as we know it, that means that our uncertainty about our uncertainty of its probability should increase our willingness to defend against its potential ~ -inf payoff, rather than decrease our willingness to.

The thing is, not only is there reasonable evidence that climate change is occurring - which reduces the hesitation to actually spend money protecting against it - but also that it's a problem that concerns pretty much every country.

> The more uncertain we are about our uncertainty of the rarity of a global catastrophe, the more rational it is for us to assume we are likely presently under-estimating its rarity

So the opposite of Occam's razor?

Think of it as Pascal's wager. We are talking about catastrophy here, the cost function is quite out of balance when looking at the alternative of "Reducing our standard of living a bit even though the catastrophy would not have happend anyway".

It took me a long while to come up with a response to this I liked, but think about it this way: there is, maybe, a 10^-a prior climate change destroys life as we know it, right? But my prior for God, heaven, etc existing is, alas, 10^-b, where b >>>>>>>>>>>>> a. (never a 0 or 1 prior kinda guy, even if I know that is dumb in some scenarios, like tautologies and impossibilities, yadada). Too many more factors would have to be revealed to me in terms of the existence of God that I would then believe that a is of similar value to b, if that makes sense? ie that they have similar probabilities (or rather, utilities, which matters since heaven is probably +inf and catastrophe of all life is MAX(badness) which we might as well call -inf, right?

So, not only is -Cost * P(calamity | investment) >> -Cost * P(calamity | not investment), Cost(investment) < [Cost(calamity | no investment) - Cost(calamity | w investment)], so its a rational purchase...

sorry if this is at all unclear, i can clarify anything

Because complexity is the enemy of robustness.

A village that lives entirely off its own subsistence farming, or a band that lives off hunting and gathering, can keep chugging along in merry ignorance of any catastrophe that does not destroy the local food supply (and if one does, they can pick up and move).

A society that depends for daily survival upon massive global flows of food, goods, and information is vulnerable to anything that disrupts those flows.

Even relatively minor changes throw our civilization and economy into panic and disarray. Drought in the Middle East is considered one of the factors that led to the rise of ISIS [0]. But it's not the first time. Drought led to poor harvest which led to the French Revolution when grain prices got too high [1].

If you're wondering why the Netherlands has to reclaim land from the sea, if you wonder where it all went, it was a result of the Little Ice Age and a storm that devastated Northern Europe and washed much the of area out to sea [2].

Of course all of this happened outside of our modern worries about climate change... but it shows even "natural" changes in weather patterns can cause serious economic and cultural upheaval. What we're being warned of right now is far more serious and massive than we've ever seen before, including during all the time periods where drought and famine and storms have famously killed hundreds/thousands before [3].

All you can do is assume the worst. We've seen the impacts throughout history, we're dealing with some of them now. Northern Europe is still paying off the mitigation of the storm that destroyed their land... that storm happened 800 years ago. They'll be paying it off forever.

If we have the ability to stop things like the Little Ice Age or the drought that caused the French Revolution, we should. Right now we're being warned of something like that, but many many times more dramatic. And we have a chance to slow it down. We need to take that chance.

[0]: http://www.politifact.com/truth-o-meter/statements/2015/sep/...

[1]: http://www.academia.edu/4794332/Drought_and_the_French_Revol...

[2]: https://en.wikipedia.org/wiki/Saint_Marcellus%27_flood

[3]: https://xkcd.com/1732/

Yes, absolutely. But the species that inhabit the earth come and go, and climate seems to be one driver.

There's a really good George Carlin bit in one of his stand-ups about how the earth will be fine. Something along the lines of what you're saying; earthquakes, volcanoes, solar flares, etc. She's been around for a looong time folks. It's humanity that might be in for a bad day.

"Save the earth? The nerve, the arrogance. Now the people? The people are f"

There's also this classic page: https://qntm.org/destroy

The difference with the past is that the sun is slowly getting hotter. Increasing the incoming solar power by a mere 10% would be enough to tip the climate into a runaway process that will boil the oceans and scour the surface. Our Earth only has a billion more years to go

https://www.sciencedaily.com/releases/2013/12/131216142310.h...

In a billion years we will find out how to countermeasure this. Is really a long time.

agree, but in the long long run it will lean towards hotter as the sun changes phases. eventually earth will be a scorched rock without anyone's help.

you have to consider, the earth is about 4.5 billion years old, and we only have 1 billion left, but life will be wiped out much 'sooner' then that.

Why does the Earth have one billion years left?

In about a billion years the sun will exhaust enough nuclear fuel to cool and expand, boiling the oceans, blowing off our atmosphere, and turning Earth back into a sterile rock.

It's predicted by astronomers and physicists who study stellar evolution.

No, that doesn't happen until 5 billion years into the future.

The Sun will gradually keep getting hotter and slightly more luminous up to that point.

Earth will be a desert long before the Sun exhausts nuclear fuel to start expanding and becoming a red giant.

All stars become gradually hotter the older they get. G-type stars like our sun are no exception to this. On a certain point in time (currently estimated at 1Gy from now), the energy output of our sun is so big, that the Carbonate–silicate cycle[0] cannot continue uninterrupted. Thus CO2 and CO cannot be absorbed by the geosphere. The breaking of this process will gradually enrich the atmosphere with CO2, leading to a runaway greenhouse effect (a bit like on Venus).

But I would not worry about that. It took 500My for life to evolve from trilobites to humans. This timespan is twice as long...

[0]: https://en.wikipedia.org/wiki/Carbonate%E2%80%93silicate_cyc...

> we only have 1 billion left

Not disputing, but have a source for that theory?

That's less comforting when you realise that cyanobacteria likely caused an iceball phase, nearly wiping itself out in the process.

I think the worst case scenario is the rising of the sea level by tens of meters over decades, destroying all coastal cities. Think the Syrian refugee crisis, but hundreds of times more people.

US and EU are doing a lot about reducing their output of CO2, but unfortunately that’s completely dwarfed by new output elsewhere: https://en.m.wikipedia.org/wiki/List_of_countries_by_carbon_...

Without global actors taking full responsibility, we are basically screwed.

I agree, but the US (and Canada, Australia, etc), still pollute twice more per capita than China. There's still a lot we can do. The EU, however, has lower per capita emissions than China. And that's ignoring that most manufactured goods we consume are made in China.

It's like whack a mole. The economy is a global system, and so is the atmosphere. Shifting production of carbon between the parts isn't per se useful.

We can no more blame other countries for increasing CO2 output than we can blame a grocery store down the block from opening when another closes (or, refuses to cater to new demand, to make a better analogy).

We'll only stop if we come up with an unambiguously better alternative, or something forces us. A acute problem is that if we stopped using carbon, people would die. (And the economy would contract, of course, but death is a stronger motivator).

We're above our carrying capacity without carbon use. But if we keep using it, we die, later.

I think the most no brainer approach is to push for a global carbon tax to prod development of renewables. Income taxes could be cut to offset, so at a low level this wouldn't hurt a country. This seems not very popular however, and no one has pushed for an international agreement on this point, instead pushing for whack a mole emissions reductions in single countries.

My most optimistic scenario is we do figure out an unambiguously better alternative, switch to it, and then also figure out some way to use the energy to suck carbon from the atmosphere (which has its own challenges).

Science isn't perfectly absolved after all many of us including computer "scientists" work closely with industry that affects global warming.

It's all about discount rate for stuff in the future. If you spend money to mitigate future damage, that's money that you can't invest productively. So basically, in economic terms, the distant future is worthless.

> decades

More than a century, in some cases.

Capitalism needs additional constraints or it will end all civilization. Simply, the cost of creating greenhouse gasses has never been priced in to the market since Exxon and the likes have lobbied hard for decades to not let the truth gain any traction. They should all be in jail and there should be no profits in destroying ecosystems. Otherwise there seems no hope.

In a socialized system you'd have the same thing, except perpetuated by bureaucrats instead of businessmen.

If anything, capitalism has an advantage in that it's at least theoretically possible to mitigate the effect of greed on politics. Throwing all your eggs into the government basket gives you no such recourse.

The Volkswagen emissions scandal demonstrated that mitigating effects will be circumvented given the presence of a profit motive. Rather than construct an elaborate and exploitable maze of incentives, perhaps it would be simpler to remove the profit motive.

That's my point. Capitalism or socialism, greed is greed. There is always a profit motive.

The general population controls so little of the economic might that this just isn't true. We could pool our votes to change the course of politics. If we pooled our dollars nobody would care.

There's nothing stopping you from pooling your votes right now.

Ownership of capital has basically nothing to do with it. If the means of production are owned by "the workers", all that ends up happening is each group of workers sends a representative to manage their share of the means of production. Unless you have a true Athenian direct democracy, it reduces to exactly the same system, just less diversified.

And yet capitalism gives us the greatest hope we have: companies like Tesla, and products like solar panels and wind turbines. None of that would exist without capitalism.

citation needed

There're two statements without any proof: 1) that only capitalist system can create electrical cars and solar panels (obviosly false) 2) that electric vehicles and solar panels are good for the nature (there's not enough data, but to manufacture both you need a lot energy and materials, and not all electricity is created by clean sources)

and yet our governments

This isn't solely the purview of governments, there are other institutions involved, including many corporations, and the specific individuals behind them. Arguably the financial world, various inter-national rivalries, media, public opinion, religions, and more.

On the one hand, if it succeeds in offing some element of, take your pick: modernity, liberal democracy, advanced civilisation, humanity, life on earth, terrifying as all get out. On the other, a maddeningly fascinating systems dysfunction at work.

Though on the whole, I'd prefer the tuition bill for this course were lower.

In all countries that matter, governments are elected. And they do what they need to do to be elected for the next term.

Assuming they really swept global warming under the rug, they did it because accounting for it was unpopular. We prefer to vote for a candidate that won't reduce our comfort rather than one who decides to tackle a problem most people don't really understand.

We are the ones to blame, governments just gave us what we wanted.

> In all countries that matter, governments are elected.

Well, except China, and Russia, two very large industrial nations that certainly matter in terms of global impact. You're kidding yourself if you believe those governments are elected.

> We are the ones to blame, governments just gave us what we wanted.

No, governments are giving their sponsors what they want. The electorate is led to believe they want it too.

The one with the most money usually wins. Until that is fixed the popularity of views seems meaningless.

US emissions have plateaued two decades ago [0]. Emissions are growing unchecked elsewhere, a combination of population explosion and rapid industrialization.

[0] http://www.climatechangenews.com/2017/03/31/chinese-co2-emis...

I'm curious if the various ways American's and America spends it's money and consumes its good is factored into U.S. emissions.

Does the carbon it takes to produce an iphone and then ship it here count? What about all the fuel/power used by military bases abroad? Does our purchasing of Foreign cars count?

Under most measures it isn't counted. What you are looking for is called consumption-based emissions accounting and unsurprisingly it shows US emissions are still going up.

Moving to consumption based accounting aligns closely with the generally accepted best economic solution for reducing emissions - a global carbon tax, which would be pushed onto developing countries as a requirement when they want to export to developed countries.

Incidentally, the US military has been exempt from all climate agreements since Kyoto, and so are international flights.

Emission growth has stopped, but what we need to do is hit net zero.

We are no closer to that today then we were 20 years ago. There isn't even a vague plan for the United States to get there.

I don't know why you're downvoted. The RCPs that show us respecting the goal of the 2C limit all show emissions need to shrink globally and reach zero around 2050 or even earlier. The fact emissions have stopped growing is not really much progress. It is like we are cruising to disaster rather than accelerating towards it.

Probably because there is no practical plan to reduce them to zero. There's much hand-wringing about future technologies, but the reality of it is that it will require drastic reduction in consumption.

Very unlikely that is the case. You are assuming that clean technologies will produce only economic cost not a net economic benefit. But that's not how technology works generally

Great, what is the national road-map for our transition to these net-beneficial clean technologies? If they are net-beneficial, why haven't we transitioned to them yet? What factors blocking this transition will be removed in the years to come, and how exactly are we going to remove them? What decade we going to hit net zero carbon?

It's like a startup saying: "Well, sure, we are losing money hand over fist, and our per-unit economics don't make sense, but you're assuming that we won't discover... Something... that will make us profitable."

The national roadmap is absolutely massive amount of R&D going into self driving cars for example or solar batteries

What exactly do self-driving cars have to do with reducing our carbon footprint?

Hell, self-driving cars are the absolutely wrong solution to this problem. Personal automobiles - a 4,000lb steel and rubber box that drives a single 160lb human around, are incredibly wasteful, energy-inefficient luxuries. Trains, buses, bicycles, and better urban planning are the real solution to low-carbon personal transportation.

There's no roadmap in America for any of those things.

Self-driving cars might make using taxis cheaper than owning a car, which will mean car users don't have to worry about how long it takes to recharge an electric car's batteries any more, or what their range is.

Electric cars (when their batteries are plugged into the grid) could also potentially make a good distributed battery, making renewable energy sources seem more reliable.

There is a good recent article about the battery system Tesla set up in Australia:

https://www.washingtonpost.com/news/the-switch/wp/2017/12/26...

Getting to net zero emissions means turning off many perfectly functioning power plants before their intended life. It means any emissions that are practically impossible to remove (eg aviation due to the high energy density fuel required) need to be balanced out by negative emissions, which remove existing CO2 from the atmosphere. This inherently (thermodynamically) has a huge cost and little economic benefit (unless you include externalities like environmental effects).

I suggest reading/watching any recent talk by Kevin Anderson at the Tyndall Institute, and this paper for an overview:

http://journals.plos.org/plosone/article?id=10.1371/journal....

Just because emissions aren't growing doesn't mean the US should do nothing, especially considering our outsized historical contributions that have lead to current CO2 levels.

https://en.wikipedia.org/wiki/List_of_countries_by_carbon_di...

As one of the largest emitters per capita(more than double CO2e pp vs the EU), and at almost 15% of world emissions, there's a ton that can be done.

A few items that are huge emission sources and could use some attention:

* The reliance on single occupancy cars (94% of commuters) with poor gas mileage and long commutes

* Heavy meat and dairy consumption leading to big agriculture emissions (especially methane from cattle)

* Dominance of low quality, single family home construction that ignores local climate - poorly insulated 2x4 houses everywhere, average building is overly reliant on always on AC or furnace

Per capita, USA emissions have declined by 21% since 1980 [0]. Is it enough? No! All the items you're suggesting should be tackled.

But we can't have an adult conversation only focusing on one element of the equation and literally ignoring the elephants in the room. The total emissions of USA are 14.34%. Cutting them to zero would be insufficient to stop the global growth to CO2 in the atmosphere. Worse, in a few years the emissions of the rest of the world would grow to compensate the zero-emissions USA and we'd be back to square one.

I have yet to see a realistic plan for a carbon-balanced world economy even in a zero-emissions USA scenario.

[0] https://en.wikipedia.org/wiki/List_of_countries_by_carbon_di...

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