So here's an honest question from an honest climate skeptic: how come every time we update our understanding of climate, invariably it turns out the climate change is worse than we thought before? I understand that science is never perfect, so with each discovery we re-evaluate our estimations about climate change, but it should be roughly 50-50. I understand a bit of bias in reporting, so I would expect to see 60-40 or 70-30, but how come it's close to 99-01? I will not pretend that I don't have my own explanations (such as big conflict of interest of climate scientists, who would see their career advance if their findings confirm the doom and gloom consensus), but would someone care to change my mind? (preferably without ad-hominem attacks).
A lot of recent updates showing more severe consequences for not addressing global warming are due to prior models making optimistic assumptions that we keep needing to strip away, and there is a lot of guess work here... Macro-climate science isn't the sort of thing you can experiment on and the historical data isn't very easy to discern and doesn't include a lot of the modern day factors.
Fair enough. This one I never saw, but I remember seeing one other article saying we now think there are more trees than we estimated before. But for every article like this there are easily 100 saying that whatever new thing we discovered points to a faster pace of global warming. Is my impression wrong?
I would guess that scientists are conservative in their predictions, so that they don't over-estimate effects. As new information comes in and predictions become more accurate, it's more likely to lean towards worse outcomes because the earlier predictions were already biased the other way.
Look, that's a possible explanation. But are you sure you are not rationalizing? They would need to quite a bit conservative so that pretty much any new update would be towards faster warming.
Here's the 2007 IPCC estimate:
"For the next two decades, a warming of about 0.2°C per decade is projected for a range of SRES emission scenarios". [1]
Now, it did appear that estimate was slightly conservative. The actual warming for the first decade according to NASA [2] was about 0.27°C.
Well, my first link follows with this quote: "Since IPCC’s first report in 1990, assessed projections have suggested global average temperature increases between about 0.15°C and 0.3°C per decade for 1990 to 2005. This can now be compared with observed values of about 0.2°C per decade, strengthening confidence in near-term projections."
But guess what. My second link, the NASA one, shows the global increase of temperature between 2001 and 2011 to be 0.03°C. The IPCC estimate was not that conservative, was it? Should I say it was aggressive by a factor of 6?
Nope, I'm not saying that. What I'm saying (and what IPCC is saying) is that generally their predictions appear to be in line with the outcome, and not to be very conservative.
> But guess what. My second link, the NASA one, shows the global increase of temperature between 2001 and 2011 to be 0.03°C.
Are we looking at the same graph? Because the graph clearly shows that yearly variation of ~0.2°C is quite normal, and picking any two years separated by 10 years is basically asking for random noise.
When IPCC said global temperature would increase "between about 0.15°C and 0.3°C" in 15 years, they didn't mean "between 1990 and 2005, every successive year will be between 0.01°C and 0.02°C warmer than the previous year." Nor did they mean the year 1990 and 2005 will be "average" years whose temperatures would be smack in the middle of the surrounding time period. To think otherwise shows a fundamental misunderstanding.
Climate scientists are not lawyers. They usually write for people with some scientific training, who can and are willing to follow their arguments for what they are.
Did you consider writing the same reply to the comment I was answering to (that 0.2 is 35% lower than 0.27). Because the same argument about ranges and variations applies. Except that that comment was left at the firm conclusion that 0.2 is more conservative than 0.27, while my reply continued with the statement that I do not think the IPCC was wrong, but rather right.
I'm not sure why you're skeptical. Scientists get a lot of flack for publishing "doom and gloom" results, even when those are accurate, and no scientist is particularly interested in overstating this effect.
Also, ".27 C" is not necessarily excluded from "about .2 C": it's not sufficient to simply compare approximate figures. There's a big difference in this context between ".2 C ± .5 C" and ".2 C ± .8 C". You would need to show that the observed result is entirely outside the predicted range, including both sets of error bars.
However, focusing on the temperature record is pretty disingenuous. It's been proven beyond doubt that humanity is liberating gigatonnes of fossil carbon, which is proven beyond doubt to warm the planet, specifically by 3.7 W/m^2 per doubling. The actual rate of warming and total climate sensitivity are interesting areas of research, but do not themselves have any bearing on whether that warming will happen.
>They would need to quite a bit conservative so that pretty much any new update would be towards faster warming
The new updates are subject to the exact same bias though, it's not like you should expect it to start biased and then just immediately track towards "honest" results. Think of it as slowly reducing the bias over time, not pegging a starting point and then immediately jumping to "honest" where you expect the changes to fluctuate in a normal-distribution sort of way.
In fact, do you remember "not bad thing come alone?". Things always can go wrong faster, and when things go wrong, them multiply and accelerate.
Think, for example, what happend if you lost your job. Then you get behind old debts. Then you get a lot of stress in family,. Then you think "lets drink a little / smoke pot" then you continue doing that....
When certains things go wrong, them multiply, amplify and create side-effects.
Or in other words, is like a computer crash. When the process get corrupted and you continue along without stop and diagnose properly...
For one thing, take the tabloid headlines with a grain of salt. This article should actually read something like "Interesting new way to measure warming oceans could be even more accurate". But in reality, they still model/interpolate the results between the many thousands of measuring points, which is still just part of the picture. Which hasn't really changed that much, just a gradual refining. Which is sort of how science works.
By the way, as a skeptic, you have access to the raw data yourself and can come up with a hypothesis that the oceans aren't warming and prove it yourself. http://www.argodatamgt.org/Access-to-data
I don't think climate change is worse than we thought. It's more that it's becoming acceptable to report it in those terms and gradually that's how the populace as a whole are coming to view it.
The key thing appears to be political will. You get the full spectrum of politicians. Some have been pushing for environmental policies since the 60's and 70's when it was very fringe (and scientists were already giving us plenty of warning - with claims of CO2 causing radical climate effects if unchecked... as it mostly has been). Then you've got the muppets who are still in denial and don't appear to give a shit about what sort of planet is left to the next generation(s).
Thanks for the thoughtful reply. I think it's very likely you are right. Also thanks for the link to the data. I tried in the past to get access to actual raw data so I can play with it, and draw my own conclusions, but all I got was always many levels above the raw data.
Your point about politicians in denial is 100% on. And as a skeptical guy it bothers me that people perceive me as being somehow in the same boat as them. It is my perception that those guys are not really trying to find truth, or what's best for humankind, or anything beyond what will get them elected in the next cycle. However, that being said, I'm still skeptical.
To give you an example, how many times did you not read in the media that Greenland is melting. Well, here's the real time data about the Greenland ice sheet mass [1]. Have you ever heard that the mass accumulation for the 2017-18 year was way above the 30-year mean?
Edit: Also, thanks the Hacker News community. This is the first time I express my views on climate change without using a throwaway account, and I fully expected my karma to take a huge hit. So far it didn't, it stayed about flat. I expected to be destroyed in the comments. Nope, all comments have been respectful. Well done Hacker News.
Not really. The 200GT/year is about 0.008% of the total mass of the ice sheet in Greenland. At this rate, Greenland will be ice-free in about 12500 years. The last ice age ended 11700 years ago [1], and at the time the Greenland ice sheet was many times larger than today. What that means is the average annual ice loss since the last ice age ended was higher than the current 200 GT/year.
My question for you would be, what exactly are you skeptical about? (Genuinely curious). Is that global climate change exists at all? Or that it’s somehow being misprepresented?
To me it’s always just come down to which do I think is more likely:
A) 99% of all scientists are intentionally duping society into believing global warming for some unknown agenda that they all share and we don’t know about for an unknown benefit
B) the people who stand to make billions (maybe trillions) of dollars by claiming that global warming doesn’t exist or is at least to some degree a conspiracy are behind the idea that globally warming isn’t real
When i want to find out who is behind something, I typically look at who stands to make the most money from their viewpoint being accepted as the dominant one.
To me it seems, given the enormous amount of money at stake, that scenario b is much more likely.
Like all things the truth is probably somewhere in the middle...
That’s a fallacy. Between anti-vaxxers and modern medicine the truth isn’t in the middle. Between Nazi ideology and its victims, the truth wasn’t in th middle. Between people who think that cell phone towers are controlling their minds with alien rays, and the rest of us, the truth isn’t in the middle.
>what exactly are you skeptical about? (Genuinely curious)
I was fully convinced that the science about global warming is settled until I read Crichton's novel "State of Fear" [1]. That one planted some seeds of doubt in my mind. I know, a lot of climate change advocates say the novel was debunked (and maybe it was), but after I read the novel, I started thinking that maybe I should take a closer look and try to draw my own conclusions.
And what I saw was not always good. Not always bad, mind you. To be honest, in the last 2 years or so, I get less and less skeptical, but overall, I still consider myself skeptical.
Let me list a few things
* A large part of Earth's land mass is in remote areas of Russia, Africa, South America. It's likely that more than 50% of the land mass does not have good temperature records.
* Many temperature stations, while somewhat appropriate for reporting temperature for purposes of weather forecast, are not appropriate for climate change science (e.g. they are located in a parking lot, subject to the heat of the asphalt).
* The temperature in a hot desert often drops below freezing during nighttime. Why? Because the air is dry, in other words the greenhouse effect is much lower. That should tell you that water vapors in the atmosphere are a very powerful greenhouse gas. Climate scientists admit as much. More powerful than CO2? Well, you will not get a straight answer to that question. You'll start hearing jargon such as "forcing", and in the end it will sound like CO2 is a more potent greenhouse gas. But behind all the jargon is the fact that CO2 in itself is not such a potent greenhouse gas, but only considering all various feedbacks (including water) that it induces. But those feedbacks are only modeled on a computer, they are not facts. Are they tested, validated, as good science would require? Oh well, it turns out that climate scientists don't believe a whole lot in falsification and validation.
* By the way, did I mention that greenhouse effect is a miss-nomer? Actual greenhouses are not hot because of the "greenhouse effect"[2]
* Bjorn Llomborg [3]. For those who don't know, the guy is a statistician who decided to take a look at the climate science through the eyes of a statistician. He wrote a book called "The Skeptical Environmentalist", which had a pretty moderate tone in my opinion. He was viciously attacked by the climate science community. For example, here's a quote from the wikipedia page: "The Climate Feedback reviewers assessed that the scientific credibility ranged between 'low' and 'very low'". If any scientist gets the modern day Giordano Bruno treatment, it's never climate science consensus scientists, always climate skeptics.
I could keep going, but I don't want to write a wall of text. I'll stop here, and if people want more bullet points, I'll put them in some separate comments.
Oh, and just to clarify. Many times I looked into the science, it did check out. For example, some skeptics point out to volcanic emissions. I spent time finding the numbers, and yes, it turns out that volcanoes emit peanuts compared to what we put in the atmosphere. I could go on with things that check out as well, but as I said above, I don't want to get people bored.
I am on a bus, but I want to point out here that CO2 is a powerful greenhouse gas because of its volume and its residence time. Its half-life in the atmosphere is far far longer than the H2O molecule, so its corresponding contribution to the greenhouse effect is also greater over time.
It depends how you look at that. Currently about 1/3 of our carbon emission are absorbed by the ocean [1]. H2O is pretty much entirely absorbed by the ocean, and then re-released (the well-known water cycle in the nature). Now, when people say that the half-life of CO2 in the atmosphere is 1000 years or so, they generally neglect that part where some CO2 is dissolved in the ocean, presumably because it can be re-released later. But that's (trivially) the same with H2O.
Crichton was not honest or well-informed. Broadly speaking, the temperature record has little to do with the validity of AGW. Suggesting that "climate scientists don't believe a whole lot in falsification and validation" is untrue, and something of an insult to the profession. Suggesting that the greenhouse effect is misnamed is a non sequitur. Your characterization of the study of H2O forcing is basically counterfactual. Berkeley Earth disagrees with your claim about temperature stations.
You don't seem to have a handle on the actual mechanism of carbon-induced warming. I find it most useful to examine science from a historical perspective: as a series of questions about the universe works. As such, I recommend The Discovery of Global Warming:
[0] https://history.aip.org/climate/index.htm
This will also tell you about how AGW was completely discredited (by multiple independent lines of evidence) for five decades, and had to fight its way back to academic credibility. That should serve as conclusive evidence that there is not a conspiracy or cabal shutting down alternative research: an 12-decade international conspiracy theory to maintain the credibility of a theory is implausible, but there's no way to reconcile that with the theory being discredited for its initial half-century.
> Suggesting that "climate scientists don't believe a whole lot in falsification and validation" is untrue, and something of an insult to the profession
I'm a quant on Wall Street. All banks have huge model validation teams. Hundreds of people at a typical mega-bank. Collectively the banking industry probably spends well north of $1 BN per year on challenging and validating models. You could say we should do that, since with the wrong models we can cause trillions of dollars of losses. And I agree. But then the climate science wants to ultimately impose trillions of dollars of carbon taxes. Why shouldn't it be subject to similar model validation requirements? Where are the hundreds of people who's job is to challenge the climate modelers? Where are the reports with the identified model weaknesses and the agreed action plans to remediate them? Oh, we have peer review? Voluntary and unpaid. Well, why are you really surprised that I'm skeptical?
There is a lot of climate model validation that goes on. I wrote a comment on another thread about just one such paper/campaign, that may help to illustrate how this works:
>mass accumulation for the 2017-18 year was way above the 30-year mean
What exactly does this mean to you? I'm curious what exactly the "a-ha" moment (even if it's relatively minor) is that you seem to be expecting when you add in the phrase "have you heard."
And I don't mean this in a negatively rhetorical way, like "what are you talking about" or anything. I'm honestly curious about your thought process when you came across this fact for the first time.
> I tried in the past to get access to actual raw data so I can play with it, and draw my own conclusions, but all I got was always many levels above the raw data.
I don't think you want to hear this, but: Do this if you want to goof around, but not if you want to reach a legitimate conclusion.
People spend their whole time in grad school learning how to analyze such data. It's easy to fall into simple pitfalls (like ignoring known calibration issues) without that kind of intense training. (This is true of any scientific measurement.)
And further, people who spend their careers on this have the benefit of critique of their initial results from their colleagues. Some of these errors are caught in conference posters and in peer review.
The best place for a determined amateur like you (or me) to start is the recently-completed National Climate Assessment: https://science2017.globalchange.gov . That will point you back into the primary literature. The amount of experience and judgement that went into that report is not something an amateur (even a very determined/intelligent one) can approach.
As a point of comparison, consider the story of Berkeley Earth (http://berkeleyearth.org/about/), which was started by skeptics but ended up reaching conclusions about rising temperatures similar to the ordinary climate science consensus. Will you be in a position to do better?
Source: I work with a couple of co-authors of sections of the IPCC and NCA reports.
Well, I'm a quant. I do know quite a lot about statistical pitfalls. That doesn't mean that I wouldn't do any mistakes if I look and analyze the data myself, but if I do and I engage people like the HN community, my mistakes will be pointed out, and it will be a learning experience, and I'll be able to progress towards a better understanding. And to be honest, I do think it's more likely than not that the global temperatures have been rising. But again, it would be nice to know you can access the data, and be able to whip out a jupiter notebook and do some sanity checks on it.
The HN community knows a lot, but not about Earth science. (Although there are some astrophysicists here.)
I have a PhD in a statistical field, and I work with PhD statisticians analyzing Earth science data. When things about interpreting results, or choosing appropriate data, come up...we talk to a domain scientist.
So I’d suggest thinking about a way to do that, if you care about the validity of your conclusions. And, as I suggested earlier, a literature review, starting with the overview reports.
I saw an interview with climate scientists and they discussed this issue. They said that the numbers they report to government agencies and other authoritative organizations are typically the more conservative end of margins in their studies due to political pressure.
Go into business for yourself with enough vitriol to gain the attention of the bannons, malkins, and coulters of the world? Join a company like shell, which has been doing “the climate science” for decades? Idk, we live in a great time for unscrupulous people, I’m sure you could find the opportunities if you tried.
First, in what way are you skeptical? That the planet is warming? That humans have anything to do with it? That it’s a result of greenhouse gas emissions? That its effects will be catastrophic?
Others have addressed your direct question in more detail: the predictions keep getting worse because a) the original predictions were conservative (“there’s no way it can get that bad”, “there’s no way we won’t begin to react”, etc.), b) we’re getting more data from recent years as the planet does begin to warm and seeing that it’s happening faster than many models predicted so new models have to incorporate this new worrying information, and c) there’s often biases in reporting on top of these other things.
Consider the ever-accelerating pace of industrialization in previously third-world countries. China currently has twice the carbon emissions of the US, and very little of that existed when climate change estimations started in the 60s.
If you want to avoid ad-hominem attacks, maybe you shouldn't present an unsubstantiated speculation about the motivations of climate scientists as your only hypothesis for 'explaining' what turns out to be (as others have pointed out) a faulty intuition?
Here's another motivation-based argument to think about: the organized, often irrational and sometimes threatening campaign of denial might have induced a tendency to discuss only the most bulletproof predictions, resulting in lowball estimates that will most likely rise as more evidence is uncovered.
> If you want to avoid ad-hominem attacks, maybe you shouldn't present an unsubstantiated speculation about the motivations of climate scientists as your only hypothesis for 'explaining' what turns out to be (as others have pointed out) a faulty intuition?
It doesn't warrant an ad hominem attack, it's pointing out an inconsistency - the claim about climate scientists' motives is as ad-hominem as many examples to be found in dictionaries. To his credit, credit_guy has been willing to consider alternative explanations than the one he started with.
The international climate reports (IPCC) are the result of a lot of scientific work followed by heavy politicking. When early reports from the scientists were alarming, the reports were watered down instead of stating the 50% case. Some of the politics came from the committee being afraid of overstating things, but perhaps a larger amount came from the US contingent basically saying they wouldn't endorse the report unless it got watered down.
What is why, as time went on, more data was collected, and the science got more confident, the results get revised upwards.
Could be that climate exhibits a lot of positive-feedback effects, more-so than most of the early models predicted. If you start by modeling climate as a linear relationship between atmospheric CO2 and temperature and then it turns out that it's that plus human CO2 production is accelerating as the developing world develops plus release of trapped CO2 in the permafrost plus decreased albedo as the glaciers melt plus the albedo effect from increased vegetation plus reduction of the moderating effect of ocean currents as they're disrupted by incoming meltwater, then you're going to continually find that your models were too conservative.
I don't buy a lot of the climate hysteria either, but for entirely different (and more depressing) reasons. I think that the reality is significantly worse than the scientists are portraying, but this doesn't matter much because we're still talking 2-4C over a century, and a century is a very long time in human progress. A century ago the world population was less than 2B, barely anyone had cars, North America and Europe were the only developed regions, coal was the predominant energy source, and hot cities like Las Vegas, Houston, and Phoenix were extremely undesirable places to live because of the lack of air conditioning. The media portrays the eventual flooding of NYC due to sea-level rise as an apocalyptic tragedy, but the fact is that several other cities (Galveston TX, New Orleans LA, Sacramento CA) have lost their pre-eminent economic position as a result of floods, and many others (Salem MA, Baltimore MD, Detroit MI and the rest of the rust belt) have from economic changes. Society adapts; people migrate and move from dying cities to new up-and-comers on more solid ground. A century is 3-4 generations, plenty of time for this migration to happen in terms of younger generations picking where they want to put down roots.
I think we're far more likely to go out in a blaze of war from the social strain that come from this large-scale migration. Humans don't do well with relative changes in social status or power levels. They tend to want to find somebody else to blame and fight. I'd give better-than-even odds that the climate is actually cooler at the end of this century than now, but only because we've triggered nuclear war and are in the midst of a nuclear winter.
You've been rejecting climate change evidence for years - your mind is clearly already made up. Nobody on this comment board is going to be able to convince you of how to reasonably react to overwhelming evidence. "Convincing" will happen when you can accept reality for what it is, instead of rejecting it for your own sadistic individualistic pleasure.
“We have learned a lot from experience about how to handle some of the ways we fool ourselves. One example: Millikan measured the charge on an electron by an experiment with falling oil drops, and got an answer which we now know not to be quite right. It's a little bit off because he had the incorrect value for the viscosity of air. It's interesting to look at the history of measurements of the charge of an electron, after Millikan. If you plot them as a function of time, you find that one is a little bit bigger than Millikan's, and the next one's a little bit bigger than that, and the next one's a little bit bigger than that, until finally they settle down to a number which is higher.
“Why didn't they discover the new number was higher right away? It's a thing that scientists are ashamed of—this history—because it's apparent that people did things like this: When they got a number that was too high above Millikan's, they thought something must be wrong—and they would look for and find a reason why something might be wrong. When they got a number close to Millikan's value they didn't look so hard. And so they eliminated the numbers that were too far off, and did other things like that....”
> Much of the data on ocean temperatures currently relies on the Argo array — robotic devices that float at different depths, surfacing roughly every 10 days to transmit readings to satellites. There are about 3,800 such pieces of equipment in waters around the globe that provide the publicly available information...
> By comparison, Resplandy and Keeling calculated heat based on the amount of oxygen and carbon dioxide rising off the ocean. Filling round glass flasks with air from research stations in the Canadian Arctic, Tasmania and La Jolla, San Diego, researchers analyzed the samples to determine the aggregate temperature of the ocean.
On what grounds is three samples of a novel measurement preferable to a few thousand direct temperature measurements? I mean in terms of reliability, not ability to generate clicks.
1. There's more than 3 samples. And they picked the locations for taking these samples very carefully.
2. They're measuring different things, obviously. One is measuring the mixture of gasses, the other is pure temperature.
The gas measurement is good for getting a picture of the entire system because it allows us to use basic chemistry, which is well understood, to gain a picture of the overall temperature change by looking at how much gas has escaped the ocean.
The ocean temperature data, while very useful, can still be subject to both sampling errors and problems with the analysis as far as how to interpret it in aggregate. Especially since you have to put overall weather patterns, like El Nino / La Nina, etc. into your analysis. There's always going to be uncertainty into how you should do analysis of the data over so many disparate points.
So, okay. We have a problem. Climate change likely with an significant anthropogenic component. I hear a lot about magic solutions like electric cars whose batteries are incredibly polluting to produce, solar farms that are super expensive and require crazy amounts of acres per watt, wind farms that kill birds and have toxic materials inside to operate. The problem, almost certainly, is mostly fossil fuels and to a lesser extent the meat/dairy industry. Let's say, hypothetically, I accept all of this. Let's say the USA and Europe do everything, everything that climate advocates suggest.
It won't matter.
The vast majority of carbon emissions and almost all of the carbon emission growth over the last 50 years has come from the developing world. Thats right. CO2 emissions haven't grown in the West for 50 years. They've shrunk in fact. [1] Seriously. Are we really talking about crushing the energy production of the poorest, most disadvantaged places in the world?
My point isn't that we shouldn't do anything. My point is the problem is way, way, way bigger and more complicated than is commonly phrased. We have to stop the developing world from accelerating out of poverty, and fast--if the climate projections are indeed correct.
This, my friends, is what we call a tragedy. The next time I hear something about the West harming the planet disproportionally, I'm going to collapse into a neutron star.
The only solution I see with any chance of working is if we start a global project to flood the world with nuclear reactors. Everywhere. Nothing else will deliver the gigawatts in time to stop the developing world from burning the planet alive.
Assuming, of course, the climate models are correct.
> This, my friends, is what we call a tragedy. The next time I hear something about the West harming the planet disproportionally, I'm going to collapse into a neutron star.
The west is harming the planet disproportionately. We've been doing it a lot longer, so most of the existing and baked in future warming was produced by the west. Apart from that we still produce a lot more CO2 per capita. The united states alone produces 15% of emissions today. The rest of the world is just trying to catch up to where we are.
The buck doesn't stop there though, a huge chunk of the developing worlds emissions are producing stuff for the west. They aren't responsible for that, we are for buying it.
It seems like you expect the poorest developing countries to lead the way. Has the west become so incapable of actually leading?
You should look at the impartial nonpartisan data I provided and do simple integration before you claim that, moving forward, the West will be what matters WRT climate change.
WRT the past, your "baked in" argument makes no sense and is in any case irrelevant. Moving forward, if the West drops to zero emissions today, the developing world will burn the planet alive, if the climate models are correct.
> You should look at the impartial nonpartisan data I provided and do simple integration before you claim that, moving forward, the West will be what matters WRT climate change.
Your source looked at cumulative emissions per country, not per capita, even then the west is way over represented in your own source.
> WRT the past, your "baked in" argument makes no sense and is in any case irrelevant.
We have 1.5-2 degrees of warming baked in, even if the world stopped pumping out CO2 tomorrow. Most of that is from the West so we are responsible for that.
> Moving forward, if the West drops to zero emissions today, the developing world will burn the planet alive, if the climate models are correct.
If we drop to zero emissions tomorrow we will have created the technology and the model for the developing world to also get there. That's what leadership is.
You make a lot of very strong claims that you think are fair handed but are terribly biased. "solar farms that are super expensive and require crazy amounts of acres per watt". We can afford to cut taxes by $100B a year despite having a budget deficit. How crazy expensive is it for the US to maintain a vast military to secure our access to oil and gas (among other things)? We can afford $700B every single year to do that, but spending tens of billions of dollars on green energy would be crazy expensive. As for acres, we have lots of them to spare.
Yes, wind farms kill birds. Do the people who point this out ever weigh that against the number of dead animals and people and reduced health from coal and oil? Do they really care about the birds? Have they ever made an omelette?
Classifying electric cars as a "magic solution" is silly; they are just one small part of an incremental solution. Nobody says they are magic or the total solution. Your verbiage is emotion based and not fact based. Apparently these tactics worked on you, but I find them lazy and not compelling.
Finally, addressing your overall point: If I'm fat, I should eat better. You are right to say that cutting out sugar from my coffee won't solve my problems if I continue eating two hamburgers and fries for lunch. But to reason that I might as well have the sugar in my coffee because I haven't cut down on everything else is just factually wrong. Incomplete solutions may still buy time to address those other issues, and incrementally reducing use may mean we still suffer terrible consequences, but perhaps not quite as intensely.
They absolutely will not buy time. The developing world is, right now, growing in carbon emissions at what appears an exponential rate while the West is reducing emissions, both absolutely and per capita.
We can't succeed at what the climate advocates think we need to do without addressing the problem of the developing world.
Let me state the point more clearly: if the West drops to ZERO carbon emissions yesterday, it won't matter.
The developed countries have the means to pioneer technology that can then be adopted by poorer countries without having to do the R&D. Preventing catastrophic climate change is not cheap, it only makes sense to have the rich countries pay for it.
BTW, developed countries are harming the planet disproportionally. Per capita emissions are way higher. What you write about solar and wind is mostly FUD.
1) we don't have the time to dither around with the latest silver reflective fads. If the climate models are correct, we must act now.
2) we already have the technology to solve the problem at scale, we merely don't have the money. The technology is nuclear power. We don't have to worry about the real estate for solar and wind.
The biggest problem is rolling back the nonsense nuclear power scares from the 70s. The second biggest problem is who will fund, build, own, audit, and operate the plants.
Wrt solar and wind, they require an ungodly amount of real estate per watt. They see untenable as a primary source of power as a result.
Without taking a position either way, my understanding of the skepticism is not that warming is not occuring, but rather the degree to which things that humanity can control influence that warming (0% to 100%).
It's not just a any single coherent opposition to global warming. You get everything, including I am sure a non trivial group of people think the climate is cooling due to man made effects to people who think man made warming exists, but it's not going to have a meaningful impact.
It's not a question of evidence at this point, it's a question of the limitless realms of ignorance.
This is exactly my experience talking to contrarians on the subject. Their viewpoint shifts subtly over time whilst continuing to oppose the consensus.
Somewhat off topic comment, but in 2003, Bill Bryson's book "History of Everything" states that anthropogenic CO2 output is 7billion metric tons per year where natural CO2 output is 200 billion metric tons a year (mostly volcanoes IIRC)[0]. It left me with the impression, that an additional 3% a year is small and we have time before this becomes a crisis. For the record, Scientific American calls Bill Bryson "A Champion of Science".
Then when climate change appeared to accelerate, I assumed that it must because we are removing our carbon sinks and that deforestation is likely the more dominant cause than our +3% additional emissions.
Earlier this week, I revisited the above figure and according to Scientific American: "the world’s volcanoes, both on land and undersea, generate about 200 million tons of carbon dioxide (CO2) annually, while our automotive and industrial activities cause some 24 billion tons of CO2 emissions every year worldwide." [1]
At 3% I can see how a climate change skeptic might feel this issue is alarmist. But if it is 12,000% I don't see how anyone could honestly be skeptical that global warming isn't being caused by humans.
It is mind boggling that two authoritative sources could differ by 3000X. Any clarifying comments are appreciated.
The human mind is susceptible to priming. When I read the SciAm article earlier this week I was sure I read "200 Billion" since that is what I was expecting. But upon reading the conclusion that number made no sense and I swear the B magically became an M.
The Sci-Am Q&A is not dated but this is and also provides enough information to look at the raw data if one should choose to, it also provides a pretty wide range for volcano output but less than 1 billion tons a year for the last 250 years.
https://www.climate.gov/news-features/climate-qa/which-emits...
Wait, so in his book, Bill Bryson casually overstated the natural CO2 output by a factor of a thousand? I have to wonder how such a massive mistake got through the editing process. It's not even a simple typo, it's the lynchpin of Bryson's argument that humans contribute a negligible fraction of total atmospheric CO2.
Comparing man made emissions against natural is somewhat misleading. The damage caused by carbon emissions is related to its atmospheric concentration, which _is_ increasing at an alarming rate. It doesn't matter if man-made emissions is 3% or 300% of natural rate, as long as the net emission, as a percentage of the carbon already in the system, is large. Carbon naturally exists in a cycle, so natural emissions is always roughly in equivalent to absorption.
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[ 795 ms ] story [ 4462 ms ] threadHere's the 2007 IPCC estimate:
"For the next two decades, a warming of about 0.2°C per decade is projected for a range of SRES emission scenarios". [1]
Now, it did appear that estimate was slightly conservative. The actual warming for the first decade according to NASA [2] was about 0.27°C.
[1]https://www.ipcc.ch/publications_and_data/ar4/wg1/en/spmsspm...
[2]https://climate.nasa.gov/vital-signs/global-temperature/
But guess what. My second link, the NASA one, shows the global increase of temperature between 2001 and 2011 to be 0.03°C. The IPCC estimate was not that conservative, was it? Should I say it was aggressive by a factor of 6?
Nope, I'm not saying that. What I'm saying (and what IPCC is saying) is that generally their predictions appear to be in line with the outcome, and not to be very conservative.
Are we looking at the same graph? Because the graph clearly shows that yearly variation of ~0.2°C is quite normal, and picking any two years separated by 10 years is basically asking for random noise.
When IPCC said global temperature would increase "between about 0.15°C and 0.3°C" in 15 years, they didn't mean "between 1990 and 2005, every successive year will be between 0.01°C and 0.02°C warmer than the previous year." Nor did they mean the year 1990 and 2005 will be "average" years whose temperatures would be smack in the middle of the surrounding time period. To think otherwise shows a fundamental misunderstanding.
Climate scientists are not lawyers. They usually write for people with some scientific training, who can and are willing to follow their arguments for what they are.
Also, ".27 C" is not necessarily excluded from "about .2 C": it's not sufficient to simply compare approximate figures. There's a big difference in this context between ".2 C ± .5 C" and ".2 C ± .8 C". You would need to show that the observed result is entirely outside the predicted range, including both sets of error bars.
However, focusing on the temperature record is pretty disingenuous. It's been proven beyond doubt that humanity is liberating gigatonnes of fossil carbon, which is proven beyond doubt to warm the planet, specifically by 3.7 W/m^2 per doubling. The actual rate of warming and total climate sensitivity are interesting areas of research, but do not themselves have any bearing on whether that warming will happen.
The new updates are subject to the exact same bias though, it's not like you should expect it to start biased and then just immediately track towards "honest" results. Think of it as slowly reducing the bias over time, not pegging a starting point and then immediately jumping to "honest" where you expect the changes to fluctuate in a normal-distribution sort of way.
Nope. That is law that don't exist.
In fact, do you remember "not bad thing come alone?". Things always can go wrong faster, and when things go wrong, them multiply and accelerate.
Think, for example, what happend if you lost your job. Then you get behind old debts. Then you get a lot of stress in family,. Then you think "lets drink a little / smoke pot" then you continue doing that....
When certains things go wrong, them multiply, amplify and create side-effects.
Or in other words, is like a computer crash. When the process get corrupted and you continue along without stop and diagnose properly...
By the way, as a skeptic, you have access to the raw data yourself and can come up with a hypothesis that the oceans aren't warming and prove it yourself. http://www.argodatamgt.org/Access-to-data
I don't think climate change is worse than we thought. It's more that it's becoming acceptable to report it in those terms and gradually that's how the populace as a whole are coming to view it.
The key thing appears to be political will. You get the full spectrum of politicians. Some have been pushing for environmental policies since the 60's and 70's when it was very fringe (and scientists were already giving us plenty of warning - with claims of CO2 causing radical climate effects if unchecked... as it mostly has been). Then you've got the muppets who are still in denial and don't appear to give a shit about what sort of planet is left to the next generation(s).
Your point about politicians in denial is 100% on. And as a skeptical guy it bothers me that people perceive me as being somehow in the same boat as them. It is my perception that those guys are not really trying to find truth, or what's best for humankind, or anything beyond what will get them elected in the next cycle. However, that being said, I'm still skeptical.
To give you an example, how many times did you not read in the media that Greenland is melting. Well, here's the real time data about the Greenland ice sheet mass [1]. Have you ever heard that the mass accumulation for the 2017-18 year was way above the 30-year mean?
Edit: Also, thanks the Hacker News community. This is the first time I express my views on climate change without using a throwaway account, and I fully expected my karma to take a huge hit. So far it didn't, it stayed about flat. I expected to be destroyed in the comments. Nope, all comments have been respectful. Well done Hacker News.
[1] https://www.dmi.dk/en/groenland/maalinger/greenland-ice-shee...
"As mentioned, satellites measuring the ice sheet mass have observed a loss of around 200 Gt/year over the last decade."
Doesn't that make the media right ?
[1] https://en.wikipedia.org/wiki/Quaternary_glaciation
To me it’s always just come down to which do I think is more likely:
A) 99% of all scientists are intentionally duping society into believing global warming for some unknown agenda that they all share and we don’t know about for an unknown benefit
B) the people who stand to make billions (maybe trillions) of dollars by claiming that global warming doesn’t exist or is at least to some degree a conspiracy are behind the idea that globally warming isn’t real
When i want to find out who is behind something, I typically look at who stands to make the most money from their viewpoint being accepted as the dominant one.
To me it seems, given the enormous amount of money at stake, that scenario b is much more likely.
That’s a fallacy. Between anti-vaxxers and modern medicine the truth isn’t in the middle. Between Nazi ideology and its victims, the truth wasn’t in th middle. Between people who think that cell phone towers are controlling their minds with alien rays, and the rest of us, the truth isn’t in the middle.
Some shit is just wrong.
I was fully convinced that the science about global warming is settled until I read Crichton's novel "State of Fear" [1]. That one planted some seeds of doubt in my mind. I know, a lot of climate change advocates say the novel was debunked (and maybe it was), but after I read the novel, I started thinking that maybe I should take a closer look and try to draw my own conclusions.
And what I saw was not always good. Not always bad, mind you. To be honest, in the last 2 years or so, I get less and less skeptical, but overall, I still consider myself skeptical.
Let me list a few things
* A large part of Earth's land mass is in remote areas of Russia, Africa, South America. It's likely that more than 50% of the land mass does not have good temperature records.
* Many temperature stations, while somewhat appropriate for reporting temperature for purposes of weather forecast, are not appropriate for climate change science (e.g. they are located in a parking lot, subject to the heat of the asphalt).
* The temperature in a hot desert often drops below freezing during nighttime. Why? Because the air is dry, in other words the greenhouse effect is much lower. That should tell you that water vapors in the atmosphere are a very powerful greenhouse gas. Climate scientists admit as much. More powerful than CO2? Well, you will not get a straight answer to that question. You'll start hearing jargon such as "forcing", and in the end it will sound like CO2 is a more potent greenhouse gas. But behind all the jargon is the fact that CO2 in itself is not such a potent greenhouse gas, but only considering all various feedbacks (including water) that it induces. But those feedbacks are only modeled on a computer, they are not facts. Are they tested, validated, as good science would require? Oh well, it turns out that climate scientists don't believe a whole lot in falsification and validation.
* By the way, did I mention that greenhouse effect is a miss-nomer? Actual greenhouses are not hot because of the "greenhouse effect"[2]
* Bjorn Llomborg [3]. For those who don't know, the guy is a statistician who decided to take a look at the climate science through the eyes of a statistician. He wrote a book called "The Skeptical Environmentalist", which had a pretty moderate tone in my opinion. He was viciously attacked by the climate science community. For example, here's a quote from the wikipedia page: "The Climate Feedback reviewers assessed that the scientific credibility ranged between 'low' and 'very low'". If any scientist gets the modern day Giordano Bruno treatment, it's never climate science consensus scientists, always climate skeptics.
I could keep going, but I don't want to write a wall of text. I'll stop here, and if people want more bullet points, I'll put them in some separate comments.
Oh, and just to clarify. Many times I looked into the science, it did check out. For example, some skeptics point out to volcanic emissions. I spent time finding the numbers, and yes, it turns out that volcanoes emit peanuts compared to what we put in the atmosphere. I could go on with things that check out as well, but as I said above, I don't want to get people bored.
[1] https://en.wikipedia.org/wiki/State_of_Fear
[2] https://en.wikipedia.org/wiki/Greenhouse_effect
[3] https://en.wikipedia.org/wiki/Bjørn_Lomborg
[1] https://en.wikipedia.org/wiki/Solubility_pump#Anthropogenic_...
You don't seem to have a handle on the actual mechanism of carbon-induced warming. I find it most useful to examine science from a historical perspective: as a series of questions about the universe works. As such, I recommend The Discovery of Global Warming:
This will also tell you about how AGW was completely discredited (by multiple independent lines of evidence) for five decades, and had to fight its way back to academic credibility. That should serve as conclusive evidence that there is not a conspiracy or cabal shutting down alternative research: an 12-decade international conspiracy theory to maintain the credibility of a theory is implausible, but there's no way to reconcile that with the theory being discredited for its initial half-century.I'm a quant on Wall Street. All banks have huge model validation teams. Hundreds of people at a typical mega-bank. Collectively the banking industry probably spends well north of $1 BN per year on challenging and validating models. You could say we should do that, since with the wrong models we can cause trillions of dollars of losses. And I agree. But then the climate science wants to ultimately impose trillions of dollars of carbon taxes. Why shouldn't it be subject to similar model validation requirements? Where are the hundreds of people who's job is to challenge the climate modelers? Where are the reports with the identified model weaknesses and the agreed action plans to remediate them? Oh, we have peer review? Voluntary and unpaid. Well, why are you really surprised that I'm skeptical?
https://news.ycombinator.com/item?id=15613090#15620293
(Please pardon the initial "straw man" sentence - the comment was directed at another post, months ago.)
What exactly does this mean to you? I'm curious what exactly the "a-ha" moment (even if it's relatively minor) is that you seem to be expecting when you add in the phrase "have you heard."
And I don't mean this in a negatively rhetorical way, like "what are you talking about" or anything. I'm honestly curious about your thought process when you came across this fact for the first time.
I don't think you want to hear this, but: Do this if you want to goof around, but not if you want to reach a legitimate conclusion.
People spend their whole time in grad school learning how to analyze such data. It's easy to fall into simple pitfalls (like ignoring known calibration issues) without that kind of intense training. (This is true of any scientific measurement.)
And further, people who spend their careers on this have the benefit of critique of their initial results from their colleagues. Some of these errors are caught in conference posters and in peer review.
The best place for a determined amateur like you (or me) to start is the recently-completed National Climate Assessment: https://science2017.globalchange.gov . That will point you back into the primary literature. The amount of experience and judgement that went into that report is not something an amateur (even a very determined/intelligent one) can approach.
As a point of comparison, consider the story of Berkeley Earth (http://berkeleyearth.org/about/), which was started by skeptics but ended up reaching conclusions about rising temperatures similar to the ordinary climate science consensus. Will you be in a position to do better?
Source: I work with a couple of co-authors of sections of the IPCC and NCA reports.
I have a PhD in a statistical field, and I work with PhD statisticians analyzing Earth science data. When things about interpreting results, or choosing appropriate data, come up...we talk to a domain scientist.
So I’d suggest thinking about a way to do that, if you care about the validity of your conclusions. And, as I suggested earlier, a literature review, starting with the overview reports.
Why do you think that?
There's a lot more money to be made by saying there's no global warming.
But I guess it's pretty lucrative once you get in.
Others have addressed your direct question in more detail: the predictions keep getting worse because a) the original predictions were conservative (“there’s no way it can get that bad”, “there’s no way we won’t begin to react”, etc.), b) we’re getting more data from recent years as the planet does begin to warm and seeing that it’s happening faster than many models predicted so new models have to incorporate this new worrying information, and c) there’s often biases in reporting on top of these other things.
Here's another motivation-based argument to think about: the organized, often irrational and sometimes threatening campaign of denial might have induced a tendency to discuss only the most bulletproof predictions, resulting in lowball estimates that will most likely rise as more evidence is uncovered.
Why would that warrant an ad hominem attack?
What is why, as time went on, more data was collected, and the science got more confident, the results get revised upwards.
The first google hit after searching on "IPCC political pressure" https://www.theguardian.com/environment/earth-insight/2014/m...
Though that report is from 2014, it has been going for 20 years.
I don't buy a lot of the climate hysteria either, but for entirely different (and more depressing) reasons. I think that the reality is significantly worse than the scientists are portraying, but this doesn't matter much because we're still talking 2-4C over a century, and a century is a very long time in human progress. A century ago the world population was less than 2B, barely anyone had cars, North America and Europe were the only developed regions, coal was the predominant energy source, and hot cities like Las Vegas, Houston, and Phoenix were extremely undesirable places to live because of the lack of air conditioning. The media portrays the eventual flooding of NYC due to sea-level rise as an apocalyptic tragedy, but the fact is that several other cities (Galveston TX, New Orleans LA, Sacramento CA) have lost their pre-eminent economic position as a result of floods, and many others (Salem MA, Baltimore MD, Detroit MI and the rest of the rust belt) have from economic changes. Society adapts; people migrate and move from dying cities to new up-and-comers on more solid ground. A century is 3-4 generations, plenty of time for this migration to happen in terms of younger generations picking where they want to put down roots.
I think we're far more likely to go out in a blaze of war from the social strain that come from this large-scale migration. Humans don't do well with relative changes in social status or power levels. They tend to want to find somebody else to blame and fight. I'd give better-than-even odds that the climate is actually cooler at the end of this century than now, but only because we've triggered nuclear war and are in the midst of a nuclear winter.
“We have learned a lot from experience about how to handle some of the ways we fool ourselves. One example: Millikan measured the charge on an electron by an experiment with falling oil drops, and got an answer which we now know not to be quite right. It's a little bit off because he had the incorrect value for the viscosity of air. It's interesting to look at the history of measurements of the charge of an electron, after Millikan. If you plot them as a function of time, you find that one is a little bit bigger than Millikan's, and the next one's a little bit bigger than that, and the next one's a little bit bigger than that, until finally they settle down to a number which is higher.
“Why didn't they discover the new number was higher right away? It's a thing that scientists are ashamed of—this history—because it's apparent that people did things like this: When they got a number that was too high above Millikan's, they thought something must be wrong—and they would look for and find a reason why something might be wrong. When they got a number close to Millikan's value they didn't look so hard. And so they eliminated the numbers that were too far off, and did other things like that....”
> Much of the data on ocean temperatures currently relies on the Argo array — robotic devices that float at different depths, surfacing roughly every 10 days to transmit readings to satellites. There are about 3,800 such pieces of equipment in waters around the globe that provide the publicly available information...
> By comparison, Resplandy and Keeling calculated heat based on the amount of oxygen and carbon dioxide rising off the ocean. Filling round glass flasks with air from research stations in the Canadian Arctic, Tasmania and La Jolla, San Diego, researchers analyzed the samples to determine the aggregate temperature of the ocean.
On what grounds is three samples of a novel measurement preferable to a few thousand direct temperature measurements? I mean in terms of reliability, not ability to generate clicks.
2. They're measuring different things, obviously. One is measuring the mixture of gasses, the other is pure temperature.
The gas measurement is good for getting a picture of the entire system because it allows us to use basic chemistry, which is well understood, to gain a picture of the overall temperature change by looking at how much gas has escaped the ocean.
The ocean temperature data, while very useful, can still be subject to both sampling errors and problems with the analysis as far as how to interpret it in aggregate. Especially since you have to put overall weather patterns, like El Nino / La Nina, etc. into your analysis. There's always going to be uncertainty into how you should do analysis of the data over so many disparate points.
It won't matter.
The vast majority of carbon emissions and almost all of the carbon emission growth over the last 50 years has come from the developing world. Thats right. CO2 emissions haven't grown in the West for 50 years. They've shrunk in fact. [1] Seriously. Are we really talking about crushing the energy production of the poorest, most disadvantaged places in the world?
My point isn't that we shouldn't do anything. My point is the problem is way, way, way bigger and more complicated than is commonly phrased. We have to stop the developing world from accelerating out of poverty, and fast--if the climate projections are indeed correct.
This, my friends, is what we call a tragedy. The next time I hear something about the West harming the planet disproportionally, I'm going to collapse into a neutron star.
The only solution I see with any chance of working is if we start a global project to flood the world with nuclear reactors. Everywhere. Nothing else will deliver the gigawatts in time to stop the developing world from burning the planet alive.
Assuming, of course, the climate models are correct.
[1] https://ourworldindata.org/co2-and-other-greenhouse-gas-emis...
The west is harming the planet disproportionately. We've been doing it a lot longer, so most of the existing and baked in future warming was produced by the west. Apart from that we still produce a lot more CO2 per capita. The united states alone produces 15% of emissions today. The rest of the world is just trying to catch up to where we are.
The buck doesn't stop there though, a huge chunk of the developing worlds emissions are producing stuff for the west. They aren't responsible for that, we are for buying it.
It seems like you expect the poorest developing countries to lead the way. Has the west become so incapable of actually leading?
WRT the past, your "baked in" argument makes no sense and is in any case irrelevant. Moving forward, if the West drops to zero emissions today, the developing world will burn the planet alive, if the climate models are correct.
Your source looked at cumulative emissions per country, not per capita, even then the west is way over represented in your own source.
> WRT the past, your "baked in" argument makes no sense and is in any case irrelevant.
We have 1.5-2 degrees of warming baked in, even if the world stopped pumping out CO2 tomorrow. Most of that is from the West so we are responsible for that.
> Moving forward, if the West drops to zero emissions today, the developing world will burn the planet alive, if the climate models are correct.
If we drop to zero emissions tomorrow we will have created the technology and the model for the developing world to also get there. That's what leadership is.
You make a lot of very strong claims that you think are fair handed but are terribly biased. "solar farms that are super expensive and require crazy amounts of acres per watt". We can afford to cut taxes by $100B a year despite having a budget deficit. How crazy expensive is it for the US to maintain a vast military to secure our access to oil and gas (among other things)? We can afford $700B every single year to do that, but spending tens of billions of dollars on green energy would be crazy expensive. As for acres, we have lots of them to spare.
Yes, wind farms kill birds. Do the people who point this out ever weigh that against the number of dead animals and people and reduced health from coal and oil? Do they really care about the birds? Have they ever made an omelette?
Classifying electric cars as a "magic solution" is silly; they are just one small part of an incremental solution. Nobody says they are magic or the total solution. Your verbiage is emotion based and not fact based. Apparently these tactics worked on you, but I find them lazy and not compelling.
Finally, addressing your overall point: If I'm fat, I should eat better. You are right to say that cutting out sugar from my coffee won't solve my problems if I continue eating two hamburgers and fries for lunch. But to reason that I might as well have the sugar in my coffee because I haven't cut down on everything else is just factually wrong. Incomplete solutions may still buy time to address those other issues, and incrementally reducing use may mean we still suffer terrible consequences, but perhaps not quite as intensely.
We can't succeed at what the climate advocates think we need to do without addressing the problem of the developing world.
Let me state the point more clearly: if the West drops to ZERO carbon emissions yesterday, it won't matter.
BTW, developed countries are harming the planet disproportionally. Per capita emissions are way higher. What you write about solar and wind is mostly FUD.
1) we don't have the time to dither around with the latest silver reflective fads. If the climate models are correct, we must act now.
2) we already have the technology to solve the problem at scale, we merely don't have the money. The technology is nuclear power. We don't have to worry about the real estate for solar and wind.
The biggest problem is rolling back the nonsense nuclear power scares from the 70s. The second biggest problem is who will fund, build, own, audit, and operate the plants.
Wrt solar and wind, they require an ungodly amount of real estate per watt. They see untenable as a primary source of power as a result.
It's not a question of evidence at this point, it's a question of the limitless realms of ignorance.
That's a fairly recent goalpost move as "warming is not occurring" has become an untenable position.
First it was: it's not happening.
Then: but how much?
Now: but can we affect it?
Soon it'll be: are we sure it's a bad thing?
Then it'll be: it's bad but it's that other guy's fault.
Contrarianism is a mouse wheel, not a ladder.
https://upload.wikimedia.org/wikipedia/commons/thumb/5/5c/Ca...
Clarification edit: Meaning I think there is a better argument in the polemic (I'm not suggesting the answer)
Then when climate change appeared to accelerate, I assumed that it must because we are removing our carbon sinks and that deforestation is likely the more dominant cause than our +3% additional emissions.
Earlier this week, I revisited the above figure and according to Scientific American: "the world’s volcanoes, both on land and undersea, generate about 200 million tons of carbon dioxide (CO2) annually, while our automotive and industrial activities cause some 24 billion tons of CO2 emissions every year worldwide." [1]
At 3% I can see how a climate change skeptic might feel this issue is alarmist. But if it is 12,000% I don't see how anyone could honestly be skeptical that global warming isn't being caused by humans.
It is mind boggling that two authoritative sources could differ by 3000X. Any clarifying comments are appreciated.
[0] https://books.google.com/books?id=_CWlKRYLbIwC&pg=PA268&lpg=... https://www.scientificamerican.com/article/earthtalks-volcan... [1] https://www.scientificamerican.com/article/earthtalks-volcan...