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This is not a discussion about nutrition, or psychology, or anthropology. It's a discussion about two very concrete questions:

1. Is global warming happening right now?

2. Are humans responsible for it?

The answer to those two questions is absolutely unreservedly settled: it's "yes". It's as settled as any question in science can be, it's as settled as the fact that electrons exist.

The point is that how is a layperson to know which sciences are trustworthy and which are not? The media and school treat all sciences as equally trustworthy, and then it has turned out that some of them are pretty bogus. (Half of all published research findings are false, John Ioannidis, etc) So the layperson should be excused for being suspicious of all sciences, in fact it's a reasonable stance to take if one doesn't have the time or interest to examine each science closely.

Of course I have a mental ranking of which sciences are to be trusted and how much, but we can't expect the general public to take such an interest. It's just all science lumped into one big bucket, and it's not pretty.

Doesn't matter. People would be more willing to take it on trust if it weren't for 1) motivated denialists 2) ex-"tobacco not harmful" mercenaries 3) useful idiots who are willing to consider [edit] the possibility they have a valid "point of view": they don't.

That's an interesting point. I guess it's on us (scientists I mean) to hold ourselves to a higher standard?

And a third: Is global warming bad?

The answer to all three is "yes", but "yes" isn't a useful answer. "How much?" has a lot less consensus (and if history is any guide, a lot less confidence).

Yes, and the fourth: "What should be done?"

The problem becomes when people roar in about 1 and 2 and then make somewhat outrageous demands for 4, without justifying 4, or often 3.

This is what upsets most people, I think, even if they are not clever enough to articulate what's going on. There's a motte of defensible science that pushes for a much less defensible list of adjacent social causes, and then any pushback on the conclusions is easily painted as being "anti-science."

I've had this exact concern for the past decade and a half. Climate change activists really aren't using logic because they completely neglect 3 and just pull an answer to 4 out of a hat. Then when people instinctively feel their answer is unreasonable, they mock them for not believing in 1 and 2.

If you have no estimate of the cost of climate change, then you also have no business proposing costly preventative measures.

If you're saying humans are responsible for 100% of climate change, it is "absolutely unreservedly" a no.

We don't know how fast the Earth is warming and we don't know how much of that warming is anthropogenic. The best "thermometers" we have are the UAH and RSS data sets, and they disagree by nearly 50% and historical data is constantly adjusted.

The only science actually settled is: the Earth is warming, disconcertingly fast, and humans are a large part of the process. Anything else even slightly more in depth is definitely not settled.

>The only science actually settled is: the Earth is warming, disconcertingly fast, and humans are a large part of the process.

This is exactly what I said. In 2., not that humans are 100% all the cause of global warming, but definitely the dominating factor.

It's not a binary question. Here are some alternative questions:

1. At what rate is global warming happening?

2. How do current temperature trends compare to historical data?

3. What is the list of causes that may contribute to current trends, and how much influence does each cause have?

4. What are the implications if the current trend continues for 100 years?

5. What are the possible responses, how much does each cost, and how how many degrees temperature reduction do we estimate for each?

We may have a pretty good idea that CO2 is driving some degree of change, the nature of the change, impact etc. is not remotely settled.

Case and point: the Met graph time scales are all cherry picked to maximise the 'visible trend' for a given activity - a rather unscientific and propagandistic approach, however good their intentions might be. In short - the charts are 'Bad Science'.

Ironically whenever I see such cherry-picking, or serious people asking 16 year old Swedish girls about 'what we should do about Nuclear Energy' - I can only be made skeptical.

We have to balance the needs of truth and actual science with the need to communicate this information into the commons.

> the Met graph time scales are all cherry picked to

Any evidence for this?

I think they simply show the period for which the data is reliable, but I'd like to know if that assumption is wrong.

If they showed data for a period where it was unreliable then I'm sure it would be hedged around with strong caveats and error bars.

As you assume it is for reliable for the period, perhaps it's good data. It does seem to be within the last century (earliest 1940s from what I can see) where decent scientific measurements would be valid and direct, rather than from centuries past where it would be necessarily indirect and inferred.

There's nothing "settled" about question #2. The extent to which humans are responsible for climate change, comparative to external factors (such as the sun heading towards the end of its hydrogen-burning life), is very much debatable.

You can use adverbs like "absolutely" and "unreservedly" but that doesn't make your statement greater than an opinion.

You know, people use that as some kind of defense, but I would find it even scarier if humans were not responsible for it.

Being responsible for about all of it makes it possible for us to be in control. Not being responsible would make the situation akin to being hit by a meteorite.

Some people might find that preferable, since they do not have to change, but I find it far scarier.

And there you find why people make up ridiculous claims and become "skeptics" when they are not that way about any other facts of their life: because if they acknowledge the truth, then they commit themselves to doing something about it.

And when you have decades of fabricated political identity that says that we can't switch from fossil fuels and we can't change any aspect of our life that threatens the profits of a few very wealthy corporations, acknowledging these facts also means going against one's own identity.

The very same propagandists that let tobacco companies persist with false claims about smoking and cancer came back for fossil fuel companies' defense with a highly honed bag of tricks.

That's why we see massive anti-science responses in these comments, just like every media mention of climate change brings out hoards of denialist a to barrage the media outlet and scientists that show up: people perceive it as a personal attack on them and act accordingly.

Seriously? Of all the possible external factors (which, by the way, have all been shown to be relatively insignificant) you pick the one that’s seven to eight orders of magnitude slower than the change we’re seeing right now?

"such as the sun heading towards the end of its hydrogen-burning life"

Yes, that event will cause the sun to start burning helium instead, and will swell to a red giant approximately the radius of the orbit of Mars.

In about 4-5 billion years.

Yes and in the meantime it's burning steadily hotter.

Completely irrelevant on the timescale of all human history, and delusional on the 100 year time scale of clear anthropogenic climate change.

Anthropogenic? People keep throwing out terms like "clear" and "settled" and when asked to elaborate give responses like "it's in the science." So what specific conclusion in the science is now beyond questioning? Citation needed.

Have you read or consulted parts of the IPCC report? That links to nearly all relevant science on this topic, and is so well understood by everyone talking about this topic, that when they say "the science" that is at least what they are referring to.

Please see the citations at the bottom:


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