[mempko]

I am often shocked how a community like HN could have so many global warming skeptics. It doesn't make sense to me because people who deal with software should understand complex systems. Should understand how hard understanding complex systems are. And should understand how dangerous it is to disrupt complex systems so dramatically like we did the climate.

[rglover]

The skepticism isn't focused on whether it's happening (or even scientifically possible), it's on how much hyperbole is attached to the claims being made and how does that align with observed/measured reality. When the news is shouting "omg panic!! code red!!" based on the least realistic models in the IPCC reports, anyone who is intellectually honest says "well, wait...what aren't we being told here?"

Because that happens more often than not, skepticism is further excited when you get politicians who claim to be in favor of climate change policy, only to then go and fly private jets, buy ocean front property, etc. This gets conveniently ignored by folks who have turned climate change into a religion.

Every time you even begin to say "hey, we should consider this..." people sperg out and start calling you a "climate change denier" or some other disparaging term. Literally turning their brains off to counter argument because they can't handle the idea that they're living in an incomplete reality.

There is absolutely nothing controversial about saying "let's look at all sides and evaluate carefully" (the scientific process as we've agreed upon it for millennia). People have been radicalized and frightened to the point where they no longer think rationally about the problem (and solutions) and instead get hyper-tribalistic, shouting down any reasonable discussion that doesn't automatically agree with their point of view.

That's why people are skeptical.

[time_to_smile]

> "omg panic!! code red!!" based on the least realistic models in the IPCC reports,

You mean articles like this Climate change: IPCC report is 'code red for humanity'? [0]

Because that specific quote, "code red" is not BBC editorialization. It is a direct quote from UN Secretary-General António Guterres [1]

> Today’s IPCC Working Group 1 report is a code red for humanity. The alarm bells are deafening, and the evidence is irrefutable: greenhouse‑gas emissions from fossil-fuel burning and deforestation are choking our planet and putting billions of people at immediate risk.

People accuse you ave being a skeptic not because you are saying "hey, we should consider this...", it's because, as exemplified by this exact comment, you are deliberately misrepresenting your position to make it seem more legitimate. "Code red" is not based on the "least realistic" models, they are based on our current pathway, that was what made the most recent IPCC report so alarming.

Climate change poses an extremely serious, near term threat to our very way of life. I know that this can be hard to accept, but it is important to, at the very least, not silence those who are pointing this out.

0. https://www.bbc.com/news/science-environment-58130705

1. https://www.un.org/press/en/2021/sgsm20847.doc.htm

[rglover]

> you are deliberately misrepresenting your position to make it seem more legitimate

I'm literally not. It's in the report [1]. Your condescension here is exactly what I'm getting at. You assume I'm an idiot because we disagree.

[1] https://www.ipcc.ch/report/ar6/wg1/downloads/report/IPCC_AR6... (Page 304, lines 15-27).

Edit: not my own math but this is important, too, and further cements my point: https://twitter.com/RogerPielkeJr/status/1424718032279011339.

[time_to_smile]

I'm honestly confused as to whether or not you are willfully trolling, tricking yourself, or just very scared. You're playing the exact tricks here that I just pointed out in the previous comment but I'm genuinely unsure of your motives. (btw, I don't think you're an idiot, I don't think most climate skeptics are idiots, I think they're terrified beyond what they themselves even realize)

The page you linked to says that RCP 8.5 is very unlikely, but none of the "code red" reports claim otherwise.

All of the "code red" reports claim that we are virtually certain to be unable to stay below 1.5 preindustrial. This is RCP 4.5 and above. Something that if we had this conversation 20 years ago was also viewed as very unlikely.

I think either you don't know or are wildly underestimating the severe impact that these alternative pathways will have on human populations. RCP 8.5 is as horrific as it is unlikely, but all the other pathways we are rushing towards are still absolutely "code red".

In the early 2000s most people earnestly thought we wouldn't get past 1C, now that is impossible.

It's not even worth getting into all the ways that many people agree the IPCC reports tend to be a bit conservative. I'm fine throwing out all of these concerns, and sticking with just the report, but even with just the report, even on RCP 4.5, we're in very real trouble. It is absolutely a 'code red'.

[rglover]

> I'm honestly confused as to whether or not you are willfully trolling, tricking yourself, or just very scared.

None of the above. I'm reading the report and forming my own opinion while factoring out the hyperbole and panic of the media, politicians, etc. My motivation is thinking for myself and considering whether all of the theatrics align with the reality in front of me (they don't).

To further elaborate on my skepticism, perfectly valid technologies that could have been implemented decades ago (while there was plenty of awareness of this problem, as well as "global cooling") like nuclear have been foolishly ignored, discredited, etc. The primary argument I hear is "too expensive" and "too long to build," yet somehow congress manages to find money for inanities to the tune of billions every year. You'd think if this was seriously catastrophic, we'd be going in to debt to finance better energy solutions.

All of what I said above combined with that tells me the motivation of the people trying to scare everyone is disingenuous. When someone's actions don't align with their speech, it's often indicative of dishonesty. Considering how much money is at stake, the probability of that is increased.

[whatisthiseven]

"yet somehow congress manages to find money for inanities to the tune of billions every year. You'd think if this was seriously catastrophic, we'd be going in to debt to finance better energy solutions."

I don't understand. The people in the US Congress are hamstringing themselves and can barely pass their own legislation, yet somehow that inaction and political gridlock, which existed and will exist regardless of climate change, is somehow proof that...climate change isn't as bad?

You know who else also has a ton of money and a willingness to be dishonest? Every company that produces or relies directly on coal, oil, and gas. They ensure Congress is useless and unable to act by funding a party that ensures nothing happens.

I don't understand this take. Those of us that want to solve climate change want nuclear, we want solar, we want it all. We want to give Hydrogen to Aluminum plants to supplant CO2 they release, we want to electricy cars, we want to feed seaweed to cows to stop their farts.

You might be arguing against a loud majority that is repeating dumb stuff, but surely HN attracts people that can ignore the bad policies and arguments and elevate the best?

[antifa]

> The primary argument I hear is "too expensive" and "too long to build," yet somehow congress manages to find money for inanities to the tune of billions every year.

Congress is full of corrupt people who can afford to move on a whim, are in the pockets of Big Oil, and plan on retiring and dying before the worst of it hits.

It's very serious, it's just not their problem.

[breakyerself]

https://www.nature.com/articles/d41586-021-02990-w

A LOT of scientists believe that we're on track for a cataclysmic amount of warming. 3C of warming is nothing to fuck around with.

[rglover]

A lot of scientists believed we were on track for a new ice age in the 70s [1] (using the same media-driven fearmongering tactics back then, too).

The point being, don't just take what you're fed. If you dig around, you might find that a lot of the claims on scientific consensus are misrepresented (as dismissed by the quoted scientists) [2].

[1] https://www.youtube.com/watch?v=eDWPOgeq7vk

[2] https://archive.md/rU2xT

[dwaltrip]

Far more scientists were talking about global warming in the 70s than a new ice age.

Source: https://ams.confex.com/ams/pdfpapers/131047.pdf

I learned of this from Vertasium's video on global warming myths: https://www.youtube.com/watch?v=OWXoRSIxyIU

[breakyerself]

The consensus on climate change is not controversial. It's been studies many times in a multitude of different ways.

Peer reviewed scientific studies examining the level of consensus among climate scientists that Earth is warming and the primary cause is human activity:

Verheggen 2014 - 91% consensus Powell, 2013 - 97% consensus John Cook et al., 2013 - 97% consensus Farnsworth and Lichter, 2011 - 84% consensus Anderegg et al, 2010 - 97% consensus Doran, 2009 - 97% consensus Bray and von Storch, 2008 - 93.8% consensus STATS, 2007 - 95% consensus Oreskes, 2004 - 100% consensus

The Cook 2016 meta analysis of consensus studies finds the rate of consensus between 90 - 100% and that agreement with the consensus approaches 100% as expertise in climatology increases.

This list is probably outdated. I put it together 5 or 6 years ago.

Then theres that survey by Science where 60% of respondents said they expect us to hit 3C of warming because of intransigence by policy makers.

[waych]

97% of scientists agree with their source of funding.

[breakyerself]

Funny how they keep saying the same shit even when climate denying idiots come to power and try to shut them up.

[breakyerself]

Why would a climate scientist in the 1970s join the small minority in publishing a paper predicting cooling?

1. They focused narrowly on studying the natural drivers of climate change without accounting for the affect of human beings on greenhouse gas concentrations.

2. They focused narrowly on the effects of human emissions of aerosol pollution without accounting for the effects of humans on greenhouse gas levels.

3. Bad science maybe.

Regardless the majority of scientists who accurately predicted warming did not just wind up on the right side of a 50/50 bet. They didn't just predict that there would be warming. They predicted the amount of warming that could be expected depending on the emission scenario that played out.

The planet is now hotter than it has been in over 100,000 years and it's also precisely how warm scientists said it would be at this time with this co2 level. It's one of the greatest predictions in the history of earth sciences and you disregard this because a different smaller group of scientists made a wrong prediction that got too much press. Makes sense.

[Klarios]

While I think you underestimate what this means for a lot of 'other' people than 'us' (comparable rich people) it has hard/deadly affects already.

And even less human critical things are also dramatic just not for everyone. When you tell me all coral reefs are dying I really think this is very bad.

[rglover]

No, my opinion includes concern for developing nations. Not allowing them to access fossil fuels or other forms of cheap plentiful energy means they can't develop properly (i.e., permanent impoverishment).

[breakyerself]

This is silly. Wind and solar are cheaper than coal and in many circumstances cheaper than natural gas. Storage tech is also getting cheaper. The capital costs of decentralized renewables are also favorable to a lot of rural parts of the world VS building out transmission lines of hundreds of miles.

Africa never really built out an extensive land line telephone system, but most Africans have cell phones now. They do not need to move through an obsolete technology in order to adopt a new one.

[rglover]

> Wind and solar are cheaper than coal and in many circumstances cheaper than natural gas.

Now do the reliability part.

Edit: Worth reading this [1] and this [2].

[1] https://www.nature.com/articles/d41586-021-01020-z

[2] https://archive.md/4D5R6

[breakyerself]

Theres a nearly limitless number of ways to store energy. Plenty of them don't require cobalt. The cheaper renewables get the less efficient storage technologies need to be to be cost effective.

Anywhere pricing of electricity fluctuates with the intermittence of renewables there is opportunity to use storage to profit. The faster we drive the adoption of renewables in the 1st world the faster prices on storage tech will drop which will benefit the developing world. Especially the parts which will never have transmission lines built out from some centralized power plant 300 kilometers away.

[SubiculumCode]

There is something about software engineering, and I'm going to get hammered for this, that seems to convince people that everyone are idiots and doing it all wrong. It might be from personal experience explaining their field to family and friends, or perhaps it's brought about by constantly building things for themselves, idk. They seem to have especial disdain for scientists, who have a long and stories reputation as the intellectual elite, which might just rub their egos the wrong way.

[nnvvhh]

I think the superiority felt by some software engineers stems from the simple fact that they are paid a lot and are seen as smart and valuable in the culture. They have economic power, and work on something that seems incomprehensible to many everyday people. The subject matter may also have something to do with it. We're taught that lots of problems can have their details reduced and abstracted away, and I think engineers can ignore the normal human elements of life that have a real effect.

This is more armchair Freudish, but I also think that a feeling of intellectual superiority makes up for other areas that are lacking in similar feelings of value and power. Life as a computer science student is not cool or fun or sexy, so you fall back on what gives you power in wider society. Sort of like the idea that poor whites fall back onto their whiteness. People jockey for position using whatever they have.

[0_____0]

Not only are they paid a lot, but they basically start their careers being paid lavishly in places like the SF Bay Area. To a 22 year old fresh grad, what does it tell you when life immediately rewards you with a top 10% income bracket out of university?

This extends to the techno-elite as well. What drives the CEO of an electric car company to declare that the way to improve urban mobility is to build roads in tunnels underground? Well, clearly he must be doing something right, he's the richest man on earth!

[spiralx]

> They seem to have especial disdain for scientists, who have a long and stories reputation as the intellectual elite, which might just rub their egos the wrong way.

Doubly so for anything vaguely related to social sciences and other fields where theorising from first principles isn't the norm. "Historical" sciences such as astrophysics and epidemiology often get short shrift here as well. Engineers in general seem to be prone to opining outside of their area of expertise, the Salem Hypothesis that a creationist with an advanced degree was more likely to be an engineer than any other field was noted back in the early days of Usenet:

https://rationalwiki.org/wiki/Engineers_and_woo

[UnFleshedOne]

To be fair, given recent reproducibility fiasco, social sciences were scorned for a good reason.

[Teever]

Is there anything to indicate that computer science and computer engineering will avoid their own reproducibility fiasco?

[AnimalMuppet]

Well... there's computer science, and then there's computer science.

All (most of?) the stuff done on P vs NP is good science that will stand up.

Studies on which language features make it better for developers are social science, because they involve those pesky humans. That stuff is likely to suffer from a reproducibility crisis.

[SubiculumCode]

reproducibility in social sciences is usually a function of a)insurmountable costs of recruiting participants, b)complexity of the questions, and c) lack of standardization of humans. Sure social scientists would like to have N=1 billion, but they'd be lucky to get funding for 1,000.

[UnFleshedOne]

One of the problems is that the humans used were pretty standard -- all psychology students. Also publication bias.

[SubiculumCode]

can't win. If your sample isn't diverse enough it isn't representative. It it is representative, its likely too small to get a reliable effect due to the number of confounds.

[SubiculumCode]

what a great link. Thanks for sharing.

[ghostwriter]

> They seem to have especial disdain for scientists, who have a long and stories reputation as the intellectual elite, which might just rub their egos the wrong way.

another reason could be that the level of reproducibility of results and openness and availability of sources (data, code, papers) in modern "science" branches is appallingly low for the software folks to take them (the scientists and their results) seriously by default.

[time_to_smile]

The bottom line is that the real impacts of climate change strike real, existential fear in a lot of HNers and many of them simply cannot handle that cognitively.

People are drawn to tech in a large part because of their belief in the power of technology and the limitless possibility of the future. The very real potential impacts of climate change in our lifetime pose as serious threat to this.

Rather than struggle with this most people here (or maybe a few loud, happy to flag comments they disagree with people) find it much easier to simply dismiss everything as excessive hyperbole.

Climate change unquestionably posses a real threat to our way of life, and at this point mitigating it does as well. People in tech are used to only thinking in terms of optimism and finding a way to solve problems and really can't deal with serious problems that might not have a solution, but rather only different forms of compromise.

Unfortunately the skeptics here are very aggressive. I have had several comments this week flagged for no other reason than disagreement (I know this because they have all been unflagged upon review).

It's somewhat ironic because this bizarre extreme reaction from this community really makes it all the more clear that something is really wrong.

[vixen99]

And what does it tell you that sadly there are bizarre extreme reactions elsewhere on this climate question? Before the British Government was forced to insist that the police use their existing powers to stop climate protesters preventing people from going about their ordinary business which including several people trying to get to hospital for cancer treatment, we learnt about non-climate-skeptic aggression on a physical level. The leader of their group famously declared he would not move even if the motorist was carrying a dying person to hospital. That's religious fervor of a kind reminiscent of the 14th C. We do indeed need to find ways of presenting our ideas and thoughts non-aggressively because none of us know the final truth about the immensely complex system that is the Earth's climate.

[AnimalMuppet]

> We do indeed need to find ways of presenting our ideas and thoughts non-aggressively...

Absolutely.

> ... because none of us know the final truth about the immensely complex system that is the Earth's climate.

Even if we did know, don't block people going to the hospital to try to prove your point. First, it's insanely un-empathetic, to the point of sociopathy. And, theoretically, you probably claim to care about the climate because climate change is going to hurt people. Second, it's not going to win friends for your movement or viewpoint. It's counter-productive, no matter how urgent you think climate change is.

[kayodelycaon]

"Global warming" in the United States is a political issue that has nothing to do with science. A lot of our news reporting has so many contrary "scientific" studies that the average person doesn't know who to trust.

Thus appeals to authority have no meaning if people don't trust that authority. The end result is anyone saying stuff they like is correct and anyone that isn't is wrong.

The US also has a problem with people active trying to cripple and downsize government because it steals their money and tells them what to do.

[bink]

I don't see "many contrary 'scientific' studies" in the news. What I do see is almost universal consensus among climate scientists that humans are accelerating climate change, with a few news personalities criticizing predictions that were off by a few degrees or inches of sea level rise and pretending that those errors somehow invalidate the general consensus. It's disingenuous at the very least to suggest that these errors disprove anthropogenic climate change or that there are valid studies that support both sides.

[mistrial9]

US Citizen here -- I think that science plays an important role on both sides, but the cynical manipulation of news stories by the Oil and Gas industry and their well-paid allies, is backfiring finally. Please note that four prominent Republican Senators with Big Oil ties gave a press conference this year, and did not deny Climate Change.. this is news

[wonderwonder]

They dont have to deny climate change, they just have to vote like it doesn't exist and blame things like government overreach or protecting jobs or energy independence. Best of both worlds, it allows them to come off as reasonable without losing any donors.

[wonderwonder]

'"Global warming" in the United States is a political issue that has nothing to do with science'

Replace Global Warming with almost any other scientific concept and you would also be right. The fact we have politicized everything in this country is not a strength and is going to have negative long term knock on effects. I see the politicization of the covid vaccine giving general anti vaxxers validation now and would not be surprised to see a resurgence of measles in the near term (couple of years). I am completely comfortable with everyone making their own choice on the covid vaccine (I am vaccinated), I get the concern and there is enough noise that I understand their viewpoint. Politicizing it though has been the wrong approach, we cant let people have their own opinions anymore, everyone that disagrees is the enemy. This is the same with climate change, immigration and presidential elections. Issue is that the political parties know that doing this makes their base rally tighter and establishes a motivational us vs them narrative. Its not going to end well.

[allemagne]

It might be true that tech people work more intimately with complex systems than people in most other fields, but that could also mean that there is more opportunity for getting away with obfuscation or representing a false level of confidence (and also dealing with people who do this).

Maybe that understanding of complex systems could be more of an unconscious understanding that talented people can act out intuitively, or compartmentalize for a specific domain.

[bts327]

Propaganda and hyperbole aside, it must be clear to even the most obtuse among us that the earth is a finite system sphere with finite system resources. Even if it isn't as bad as we're being led to believe, the steps we could be taking to mitigate a positive feedback spiraling collapse in the system loop are things we should be doing anyway. I don't see how anyone here can argue that generating millions of one-time-use plastic receptacles is a good idea in any system or in any way sustainable long term, so what is the harm in making the changes we should be making now, as if it were as bad as we're being led to believe?

[xscott]

Why do people conflate climate change with plastic? Does creating reusable glass or metal containers use less energy or create less CO2 than making things from plastic?

Plastic pollution (particularly in the oceans) is really disturbing, but other than burning it, I don't see what it has to do with warming.

[brnt]

Before we were concerned with the climate, we were with the environment. The amount of plastic pollution, especially the potential impact of microplastics, is part of that, like global warming. At least in my view, I see them all as negative impact on our environment. At minimum, negative for ourselves.

[xscott]

Mercury, pesticides, and plastics in the ocean are horrible in my opinion. However, I've seen more than one person who seems to think recycling is going to have an effect on atmospheric CO2 levels.

[refurb]

I would say it's the opposite - those who have experience with complex systems understand how hard it is to accurately model them. And the climate models have shown that - take a look at the "global warming hiatus" from 2015. Major journals published evidence to explain the hiatus, then a few years later the conclusion was "there was no hiatus". It's pretty clear we can't even accurately tell what level of warming is happening.

[mythrwy]

An understanding that dealing with super complex systems with lots of interacting variables are very hard to accurately model and prediction value is likely to be low?

Plus maybe just a general distaste for propaganda.

For my own part I believe humans are affecting the climate to some extent. I don't see how anything else would be possible.

But I'm early 50's and have been watching this closely for 30 years and don't believe the hype and doomsday predictions anymore. I don't think the models are good enough to say what will happen in sum. Should we get off fossil fuels and stop polluting? Yes as fast as practically possible. Is OMG the world ending oceans collapsing 12 years from now? Probably not and they don't actually know that.

[moistly]

> But I'm early 50's and have been watching this closely for 30 years

Likewise. And what I’ve noted is that the IPCC’s optimistic predictions keep proving far too optimistic, and their worse-outcome predictions keep coming true, sooner than predicted.

I also see corporations that are loathe to change suddenly make commitments to change, and to make those changes pretty quickly. To my eyes, that is a big indication that things have started going well off the rails.

I’m not looking forward to having to handle the wheels falling off of society in my senior years as crop failures, infrastructure collapse, and social unrest kick into high gear.

[mythrwy]

That's really strange, I'm curious what you have seen in the last 30 years that makes you feel catastrophe is more imminent (climate wise, not social or geopolitical, we probably agree that is off the rails lol).

The polar ice caps were predicted to be gone. Still there. Coral reef collapse. They are flourishing. Massive rapid sea level rise. Very small, unnoticeable without measuring equipment. Increase in extreme weather events. Hasn't happened.

In short, things aren't a whole lot different then they were 30 years ago. I realize 30 years isn't that long but still, there were some really extreme predictions (and I was worried) but they don't look to be coming to pass and I don't think they will for the next 30 either.

[moistly]

The polar ice caps were at the lowest volume ever in 2017, and have broken records continuously this past decade or so: “Still there” is a disingenuous dismissal of their morbid condition. http://psc.apl.uw.edu/wordpress/wp-content/uploads/schweiger...

The coral reefs are collapsing. To claim otherwise is simply ludicrous. https://www.cell.com/one-earth/fulltext/S2590-3322(21)00474-...

Sea levels are rising an eighth of an inch a year, and over 2 ½ inches this past forty years. This is noticeable. https://oceanservice.noaa.gov/facts/sealevel.html

Extreme weather events have doubled in the past two decades. https://e360.yale.edu/digest/extreme-weather-events-have-inc...

You are deeply uninformed.

[mythrwy]

Extreme weather events haven't doubled in the past two decades. That is ludicrous. Additionally the article you link doesn't even say that.

Neither are the coral reefs collapsing.

https://www.royalgazette.com/environment/news/article/202108...

(btw this claims sea level rise is less then 1/10 of an inch year, not 1/8).

Great Barrier reef has record levels of coral this year.

I've personally observed many sections of the second largest reef in Mexico/Belize within the past few years and the corral are healthy with many young corral and look pretty much as they did when I first saw them 30 years ago.

The reefs are not collapsing. This is reality, not propaganda, not the output of theoretical models. How do you square this with some of the more extreme predictions? It is very interesting how we both have watched over the same time period and see different things apparently.

I don't believe I'm uninformed at all. I just don't believe the hype anymore.

[moistly]

You have no idea what you’re on about. You should have indicated that you’re a denier, and saved me this waste of time. Good luck.

[tejohnso]

> The polar ice caps were predicted to be gone

By when? Lots of climate hyperbole is focused on the year 2100 for some reason so perhaps that's what you had in mind. Anyway, not completely gone yet, but I can point out the following since I have it handy here:

July 2020: The last intact ice shelf in the Canadian Arctic fell into the sea

"We have already lost the frozen Arctic"

https://thehill.com/opinion/energy-environment/583115-climat...

> Increase in extreme weather events. Hasn't happened.

Are you just making shit up? According to the United Nations Office for Disaster Risk Reduction, extreme events are up 74% for 2000 to 2019 vs 1980 - 1999. And "Much of the difference is explained by a rise in climate-related disasters including extreme weather events: from 3,656 climate-related events (1980-1999) to 6,681 climate-related disasters in the period 2000-2019. And "The last twenty years have seen the number of major floods more than double, from 1,389 to 3,254, while the incidence of storms grew from 1,457 to 2,034. Floods and storms were the most prevalent events."

https://www.undrr.org/publication/human-cost-disasters-overv...

Also, shipping lanes opening up in the arctic for longer duration now. And of course Russia and US are considering more drilling now that it's feasible, in case anyone was confused about any real change in policy / mindset.

[mythrwy]

http://www.stormfax.com/huryear.htm

I don't see a clear trend in number of hurricanes. Sorry. I'd have to look at how "extreme events" were ascertained (hopefully not cherry picked) in the 2 20 year periods by the UN article you link.

I just don't see, from casual observation, an increase in floods and storms over when I was a child. Maybe it exists and I just am not picking it up but it's not "double" and the storms are certainly not worse.

I do understand the sea ice in the Arctic has been shrinking for some time. Paradoxically it's not in the Antarctic. This could be partially due to warming (which I agree exists, no argument). It could also be due to dark soot accumulation on the snow/ice to some extent causing more rapid melting.

This is what I'm talking about. This kind of thing.

http://news.bbc.co.uk/2/hi/science/nature/7139797.stm

[tejohnso]

> This is what I'm talking about. This kind of thing.

I see. I suspect there would have been a lot of similar articles around that time. Maslowski made that projection in 2007, a year when there was a huge drop in extent minimum over the previous year, and following successive years of lower minima before a recovery in 2008. He made the same mistake during the 2012 record minimum year (which is still the record minimum year), predicting ice free summers by 2016 if I recall correctly. He has since continued his research, but no longer makes these kinds of predictions.

So yes, sometimes there are overly aggressive projections and or outright mistakes, and on top of that there is hyperbole with the media going for the most extreme headline possible. But the fact that some predictions are overly aggressive doesn't mean the situation isn't serious. All trends based on measurement (not projection) are showing the cryosphere is in serious trouble. Glaciers are melting, permafrost is turning out to be not so "perma".

[pharmakom]

I once met a developer who claimed he didn’t believe climate change was real because the software used for modelling isn’t used by many people and probably has lots of bugs. I don’t agree, but it was an interesting take.

[xscott]

Bugs and grad student software aside, ask anyone who thinks they can rely on a model to predict the future to implement a model of: a simple pendulum, a double pendulum, the three body problem, the stock market, and then finally the climate.

Those are roughly in order of difficulty, and if they fail at an earlier one, you shouldn't trust the later ones. The first one isn't even chaotic, and I wouldn't trust a model built from first principles alone to be in phase past a dozen cycles or so.

You can curve fit things after the fact (interpolation), but extrapolation is always on shaky ground.

[smaddox]

Large scale climate models are more like modeling the possible energy distributions of such pendulums into the future. That can be done analytically for pendulums. You can do it analytically for very simple models of climate, too, but more complex models that include enough of the forces to be predictive require computers.

[xscott]

I've heard similar arguments before, but the details really matter. The amount of heat and CO2 is going to rely on things like albedo on the ground and from cloud cover, as well as plant mass and more. I think it's a mistake to ignore feedback on any of that, and it doesn't take too many moving parts with feedback to create a chaotic system.

If nothing interacted with each other, I think you could make reasonable energy-in / energy-out models. However even looking at big low-pass averages, plants/algae use CO2, and heat creates clouds, and clouds block sunlight, and so on. Unlike a double pendulum that bleeds a small amount of energy to friction, the climate bleeds a lot of energy into space, and the amount of energy it loses is a function of clouds, plant life, etc.

[smaddox]

Sure, but we know it's near equilibrium, at least on human time scales, or the climate would not be stable enough for humans to evolve. So it's not chaotic like weather is chaotic.

[xscott]

> So it's not chaotic like weather is chaotic.

I politely disagree, but my non-expert arguments shouldn't carry much weight. Here's a quote from a 2018 IPCC document instead:

    "The  climate  system  is  a  coupled  non-linear  chaotic  system,
    and therefore the long-term prediction of future climate states
    is not possible.  Rather the focus must be upon the prediction
    of the probability distribution of the system’s future possible
    states  by  the  generation  of  ensembles  of  model  solutions." [0]

I'd kind of like to dive in to the topic of whether an "ensemble of model solutions" is a fair and sufficient sampling of the problem space to trust the statistics, but I don't have enough details. However, I have done particle filters before, and when you have more than a few parameters to estimate, you need a shit-ton of particles before you can trust the statistics you get out. And that's with well behaved and fairly linear systems.

[0] https://www.ipcc.ch/site/assets/uploads/2018/03/TAR-14.pdf