I'll believe it when I see it. We have at least 40% larger ice sheets now than in 2012, and more than in 2006 [1]. See also [2].
These models have been shown to be wildly inaccurate at empirical prediction [3], so I think we need to work harder and exercise more scientific skepticism before creating alarmist headlines in the mainstream media.
> please explain why I shouldn't exercise scientific skepticism
Linking to blog posts is not "exercising scientific scepticism". It's a fucking biased blog post that's just another echo in your echo chamber. Here, let me try:
Obama is a space lizard[1][2][3]
Edit: To all the downvoters, please explain why I shouldn't exercise scientific scepticism relating to how the mainstream discusses the presidents reptilian status?
FYI the doctor is a "young-earth creationist" who has a PHD in an unrelated subject. Here's him arguing about how evolution is rubbish[1], perhaps we should listen to him because he's a doctor don't you know?
The other two sources are essentially reblogs from patently biased websites with an agenda to push, one by a neo-conservative (wow unexpected) and the other unnamed.
If you'd spend a little time critically thinking about your sources rather than using them to confirm some bias of yours you'd have already discounted them as trash.
Yes, different underlying religious and political views than mine of the author make what they're saying invalid. Gosh, I wonder what would happen if the authors of Nature papers had to reveal their political affiliations on every article they published. Can I discount someone's argument just because they support the Green party?
I don't agree with creationism in any form, but that doesn't mean that someone who does is wrong when they quote Al Gore, post a picture of a graph, or try exercising critical thinking about a topic.
> Yes, different underlying religious and political views than mine of the author make what they're saying invalid
No, him saying the Earth is between 5,700 and 10,000 years old makes what he's say invalid. Him saying evolution is rubbish and believing word for word an ancient religious text condoning all kinds of crazy stuff makes what he says invalid.
If you actually stop for a second and start critically thinking rather than just repeating it in sentences as if it's some kind of defence it's fairly obvious that your source doesn't pass any kind of litmus test for scientific credibility. I judge some of his views on par with thinking Obama is a space lizard, but you appear to be saying "hey let's conveniently ignore all that other crazy stuff he says because his views match mine and CRITICAL THINKING".
Practice what you preach.
Edit: fuck me sideways he sources the Daily Mail, what a train wreck. Are you kidding me? This is too perfect, you can't actually believe this guys anything other than just another crazy fundamentalist can you? Take a hard long look at what you read please, if you want to post that crap somewhere I would suggest sending it to your fellow "critical thinkers" and not HN.
Yes, different underlying religious and political views than mine of the author make what they're saying invalid.
Not by itself, but combine those views with the fact that the source used from the blog post is the Daily Mail, I'm comfortable ignoring the rest of the content.
Here are some papers, from climate scientists, acknowledging that models need to be re-evaluated since they've tracked poorly with climate change over the past decade.[1][2]
Steven Novella, a scientific skeptic (http://theness.com/neurologicablog/index.php/the-arctic-sea-...), summarizes it well: Arctic sea ice is undeniably decreasing over the last 36 years. The long term trend is clear. Those who want to deny this trend, however, focus on short term data because you can cherry pick any conclusion you wish.
It's pretty stable during the industrial revolution, when CO2 production really was kicked up a notch. Also, the rate of sea level rises rose at a much faster rate say 10,000 years ago than they're rising right now.
What I'm trying to say is that I think these temperature trends are more macro on the order of thousands of years, and probably mostly out of our control. I think what we're seeing now with contemporary research - 10 years ago, or 40 years ago - is mostly noise.
Chart 1: take a look at the scale, it says "millions of years." The predicted sea level changes would be fine and easy to deal with if they were projected to happen in a million years, not in a few decades.
Chart 2: again, the scale, it's thousands of years. A thousand years literally take up 20 pixels in that chart, so the beginning of the industrial revolution was about 5 pixels from the right. It's literally smaller than the dots used to mark the data points. Also, CO2 and greenhouse gasses released due to human activity are higher now than they have ever been in history: https://upload.wikimedia.org/wikipedia/commons/c/cb/Global_C... (this whole chart fits inside the last dot on your second chart.)
That's interesting because you're link [2] is the same source used in my link [2]. There's less ice in the arctic, more in the antarctic from what I can tell. The latter is a pretty big contradictory data point in the typical mainstream climate change narrative, particularly the one peddled by the likes of Al Gore et al.
Here's what I think. People are being overly alarmist and it's driving policy. Nature goes it cycles, on the order of maybe hundreds or thousands (or more) years. It's been way colder in the past than it is now, and it's also been way warmer in the past than it is now. We should reduce CO2 emissions insofar as it affects the health of people, such as smog in China.
But have we definitely teased out our effect on the temperatures from what the earth is doing on its own anyway? I'm still skeptical. Who knows, maybe there's a pattern in the earth's cosmic orbit that accounts for 99% of the warming. Or maybe it's only 1% and we're the 99% cause and Al Gore was right. But until I see this definitive proof, I have to stay skeptical.
> Here's what I think. People are being overly alarmist and it's driving policy. Nature goes it cycles, on the order of maybe hundreds or thousands (or more) years. It's been way colder in the past than it is now, and it's also been way warmer in the past than it is now. We should reduce CO2 emissions insofar as it affects the health of people, such as smog in China.
But have we definitely teased out our effect on the temperatures from what the earth is doing on its own anyway? I'm still skeptical. Who knows, maybe there's a pattern in the earth's cosmic orbit that accounts for 99% of the warming. Or maybe it's only 1% and we're the 99% cause and Al Gore was right. But until I see this definitive proof, I have to stay skeptical.
These, by the way, are a common defenses used by skeptics: this might be a cycle and not understanding what is meant by global warming. The preferred term is climate change. Yes, it has been colder in the past, and yes, it still snows. What has changed is the pattern of cold weather. Here's a relevant XCKD: https://xkcd.com/1321/. Essentially, it get cold, but it's doesn't stay cold. Also, the patterns of storms have changed. We've always had blizzards and tropical storms, but the intensity of these storms has ramped up.
The claim of a cyclical nature is questionable considering the data highly suggests a correlation between rising CO2 levels and the global temperature. The point that is missing out is that this is referring to the global average warmth, and our weather systems are VERY sensitive to this. Even a small change, like 2 to 4 degrees will have devastating effects.
Globally, sea ice is declining, and has been for a while: http://earthobservatory.nasa.gov/IOTD/view.php?id=85246 (That's pulled from the end of the blog post I linked elsewhere.) Quoting directly from what I just linked:
Claire Parkinson (http://science.gsfc.nasa.gov/sed/bio/claire.l.parkinson) has been studying polar sea ice for about four decades. She has been speaking to public audiences for nearly as long. And it was those public audiences who provoked one of the NASA climatologist’s latest research projects.
“When I give public lectures or talk with people interested in the topic of polar ice, somebody will often say something like: ‘Well, the ice is decreasing in the Arctic but it’s increasing in the Antarctic, so don’t they cancel out?’” said Parkinson. “The answer is no, they don’t cancel out.”
> Here's what I think. ... Nature goes it cycles, on the order of maybe hundreds or thousands (or more) years. It's been way colder in the past than it is now, and it's also been way warmer in the past than it is now
People think all sorts of interesting and plausible thoughts and hypotheses; that doesn't make them correct. People once thought the Sun revolved around the Earth, which seems plausible when you look outside. How do we distinguish between true and false hypotheses? Science!
The hypothesis you describe is interesting but not a new one. It has been carefully considered and ruled out by almost all scientists involved - based not on an idea in someone's mind but on extensive evidence, it's almost certain that global warming is caused by humans. A good place to read about the evidence would be the IPCC[1]; their summary reports are succinct, and written clearly for non-scientists.
We'll never be absolutely certain, but we'll never be absolutely certain of anything and would never take any action if we waited to meet that standard. What will you say to the millions who die, starve, lose their homes and wealth: 'I didn't know?' We could not have more or clearer warnings. I feel we have a great responsbility and need to act immediately or blood will be on our hands, just like the people who refused to act in the face of catastrophes in the past.
> Nature goes it cycles, on the order of maybe hundreds or thousands (or more) years. It's been way colder in the past than it is now, and it's also been way warmer in the past than it is now.
I'm pretty sure that climatologists are acutely aware of the nature of the climate.
> But have we definitely teased out our effect on the temperatures from what the earth is doing on its own anyway? I'm still skeptical. Who knows, maybe there's a pattern in the earth's cosmic orbit that accounts for 99% of the warming. Or maybe it's only 1% and we're the 99% cause and Al Gore was right. But until I see this definitive proof, I have to stay skeptical.
According to the IPCC AR 5 (which I'm sure a well-informed skeptic such as yourself have perused), there is a 95-100% probability that greenhouse gas emissions resulting from human activity are responsible for at least half of the warming observed from 1950-2010. Are you not satisfied with this certainty level?
I think it's a lot easier to accept man-made global warming when you realize how significant humans are on a global scale.
There's two numbers that blow my mind every time I think about them.
The first is the energy produced by the radioactive decay at the fiery core of the Earth: 45 terawatts. That power is enough to move the continents around the globe.
The second is the energy produced by human industry -- all of our coal plants, oil burned, nuclear power, solar & wind, the whole 9 yards: 16 terawatts. That's 1/3 the power generated by the entire rest of the Earth, down to the core, and it's growing: if it grows at the same rate as it has historically, in 25 or 30 years we'll surpass the core entirely.
Humans aren't just insignificant specks on the surface of the Earth, we're major players, comparable to its fiery core. Knowing that, is it so surprising we can affect the climate significantly?
It's cool that you're really into being skeptical and evaluating evidence and stuff, but have you considered that you aren't putting enough thought into what "definitive proof" is? There's no a priori definition of definitive proof, only what satisfies the inquirer. Why aren't you skeptical of your standards when they fly in the face of consensus amongst thousands of professional scientists?
This is a challenging viewpoint. It could theoretically be correct, but what if it wasn't? What if there truly is an imminent threat to the stability of our civilization, and we are still debating its existence when we should be acting?
This is where examining the evidence and arguments is important. If this whole thing were a conspiracy propping up unnecessary research, then the arguments would be weak and the evidence would be inconclusive. Unfortunately for humanity, this is not the case.
I personally tend to think the majority of scientists are probably right when they say global warming is happening.
At the same time, I think changing our own standards of proof based on what sways "the majority of experts" is dangerous. There are lots of examples of "the majority of experts" being wrong. For some examples, see the roughly every 200 year cycle that repeats (my observation while reading the book) in The History of Mathematical Thought I-III by Kline.
Scientists perform peer review to make sure their standards are well calibrated. If you're not relying on scientists and their work, then where do your standards of proof come from?
There are plenty of cases in biology recently where results published in respectable peer-reviewed journals have not held up. As I said, generally I believe the consensus opinion of the experts, but I also think it's occasionally reasonable not to do so automatically.
I think this is the misunderstanding: I did not say to adopt the majority opinion. I said to consider the majority opinion being different as evidence that one's methodology needs to be reexamined.
People who call themselves skeptics and disagree with mainstream scientific consensus hardly ever consider the issue. How are so many thousands of scientists so incompetent at evaluating their own data, but me, the armchair reviewer, knows what's up?
Well, I don't know why people are down voting in particular.
But exercising "scientific" skepticism would involve citing real (i.e. primary) sources, not blog posts that don't seem to be able to cite properly either. Otherwise it's just skepticism.
Certainly not from the insanely warm, practically snowless winter we've had in the northeast US.
Everybody's perfectly happy to believe the climate scientists when they say "That's mainly due to El Nino this year."
Then the next day the same scientists say "CO2 emissions are affecting the climate" and we're back to "What global warming? If I can't see something it doesn't exist."
Honest question. If 99% of scientists and astronomers said a giant asteroid were headed to earth, and within 10 years, all life on the planet would be destroyed. Would you believe it?
For something as (relatively) easy to predict as asteroid trajectories, I would be very curious why the 1% disagree, or whether it really is 99% given that exact phrasing with no qualifications. It invites scrutiny, but also invites not being certain either way (though I would err on the side of that large a majority even if I'm not certain). I posted this quote by Bertrand Russell almost a month ago, it's worth a repost: "(1) that when the experts are agreed, the opposite opinion cannot be held to be certain; (2) that when they are not agreed, no opinion can be regarded as certain by a non-expert; and (3) that when they all hold that no sufficient grounds for a positive opinion exist, the ordinary man would do well to suspend his judgment."
It's a good quote, but it is based on the premise that all the experts are equally qualified and have no conflict of interest. I am not convinced that is the case, which means we all have to find our own way. Hence all the discussion, I guess :)
I thought of disputing the "scientists and astronomers" bit in the parent (what do botanists generally know of orbital dynamics that make them any more qualified to comment than anyone else who took a few physics courses in high school / college?), it should really be restricted to domain-relevant experts which would then make it easier to take the claim that they're all more or less equally qualified. You're right there are lots of incentives in play that don't always make finding the truth the best course of action for either an expert or a so-called expert. As a layman on the subject I don't have much to contribute on the topic and would rather study other things. Though when I see the occasional chart (as the paper you linked above has) and notice that, while not "wildly incorrect", predictions have generally been "incorrect" over the last 15 years, or when I notice a shift or new emphasis in narrative, I end up feeling justified in my suspicions on the epistemic virtues (let alone the actual claims argued for being true or false) of the relevant experts. It's like, seeing all the issues with replication and so on in Psychology, how can you not help but feel like the entire field would be better off starting from scratch with rigorous methods?
Not as a certainty, no. Given that kind of time frame and a very far object, neither our measurements, nor our calculations could possibly be precise enough to know anything other than a probability of an earth impact.
Unless we are talking about a big object hanging out nearby, slowly getting closer, in which case I have plenty of non-scientist acquaintances who will be pointing telescopes at it and verifying.
Is it really 10 years? Within our lifetimes? Within 50 years?
I really wish someone would nail down a definitive timeline to when someone should really worry about climate change.
I mean ordering the world's problems big to small, I'd say unemployment, income inequality, and stagnant economic growth are more important things to worry about.
In your own lifetime it does make more sense to worry about those short term things - in comparison to climate change, the inequity / unemployment / economy change very quickly. If you have children or are worried about the survival of our species, then climate change is a far more important problem.
I'll believe it when I see it. We have at least 40% larger ice sheets now than in 2012, and more than in 2006 [1]. See also [2].
These models have been shown to be wildly inaccurate at empirical prediction [3], so I think we need to work harder and exercise more scientific skepticism before creating alarmist headlines in the mainstream media.
[1] https://www.commentarymagazine.com/culture-civilization/popu...
[2] http://blog.drwile.com/?p=12927
[3] http://objectivescience.net/warming-predictions-vs-real-worl...
Edit - to the downvoters, please explain why I shouldn't exercise scientific skepticism relating to how the mainstream discusses climate change.