there are hundreds of sources of primary research
which shall I trust?
This Judith Curry person seems reasonable, but should I trust her?
It's obviously very complex and the best sources will admit that they really aren't certain about their projections
I have this issue and I know that politicians struggle with whom to trust.
It's a really hard thing to say. You could write a book on it. In fact, I've kinda thought about writing a book called "The Internet Polymath" all about using the internet to rapidly accelerate the learning curve of nearly any discipline. And a good portion of it will be written about how to evaluate online communities and sources, how to identify trustworthy places vs red flags to be avoided, etc.
I'd say there are a lot of things to consider:
- First and foremost, cast your net widely. Do not limit yourself to one "side" or the other. Confirmation bias is dangerous, and when you're learning about what the "other" side believes from your own, you know you're getting a distorted view.
- When reading the "other" side, read their *best* and most credible sources, not their hacks. It's easy to form a poor opinion of a position if you're only reading the worst sources.
- Look closely for flaws in someone's evidence, someone's reasoning, etc. Again with confirmation bias, don't look for flaws in the "other" position but uncritically accept what your own "side" says. With confirmation bias, I actually advise to try to be MORE critical of your own side, because your brain naturally wants to be critical of the other side and not your own. So you have to work at it.
- Be wary of anyone who is too sure of themselves. In anything scientific, those who sound the most definitively sure about anything are typically trying to sell you a position, not trying to search for truth. Only Sith deal in absolutes.
- The corollary to that is try to read the people that give the opposing side the most fair treatment, that takes their strongest arguments and try to rebut them with reasoning and argument, not dismissive rhetoric. The little I've read of Judith Curry, I think she does this. However per #1, you should also read the sources critiquing Curry's work, to get both sides.
- Credibility is hard to earn, but easy to lose. For example in 320's latest link, the source is one that would be hard to give credibility w/o study. However with two basic claims (that humans are only responsible for 4% of the CO2 in the atmosphere, and that current CO2 levels are high b/c of the medieval warm period), the guy basically shot himself in the foot. I've studied this enough to know that the first claim is BS. And although the claim of lag between temp and CO2 is there, there's no logical way to explain why a very slightly warmer period hundreds of years ago could be the cause of the massively high (410 ppm) CO2 levels we see today. 295 ppm? Sure. 410? No logical way to square that circle.
- Use your gut. If someone sounds like they're full of shit, they probably are.
Finally... You shouldn't "trust" anyone. That's the point of "Never allow anything to pass the verdict of your own mind." The minute you trust a source, and stop looking at what they say with a critical eye, you're ceding control of your own beliefs to someone else. That's something you should never do.
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Now, this is all
hard work. And at the end of the day, when it comes to something like global CO2 emissions and climate change, you or I as individuals basically make just about zero difference at all. There's a thing called "rational ignorance" where the ability to affect something simply isn't worth taking the time to learn it. Regardless of anything about CO2 emissions, even if I convince you and 320 of everything I say, the world is going to either succeed or fail regardless of anything we type here. So if all this critical thought seems like it's not worth it? It probably isn't, to be honest. It's pretty much intellectual underwater basket-weaving, and little more.
However, I'd say that if you want to actually discuss these things in an online forum such as this, the above list should be the "table stakes" that you're expected to bring.
