Your quest for a large impact is noble, but I encourage you to think more locally. Consider your community first, because it's where you have the most direct levers for change. Hell, you could have a book club. You could write up an e-mail to your friends with the climate policies of relevant political candidates, "just FYI!".

There's a middle ground between "I'm buying local produce for myself" and "I'm quitting my job and chaining myself to an oil tanker."

I agree with you, but talking to my local community doesn't feel like it has an impact – everyone I know already agrees with me. All the candidates in our local elections claim to be "green"-focused. I'm wondering, where is the guidance for this? All successful social movements have been guided by leaders with clear expectations and guidelines and suggestions for people at every level of the movement to contribute. Seems like incredibly low hanging fruit to set up a "are you doing the right thing for climate change? do these things for these impacts" checklist, but I don't have the expertise to create that myself. Without it, any time anyone asks me how do I know what I'm doing/recommending will have an impact, I'm reduced to saying "someone on the internet who says they're a climate scientist told me so in a comment."

Sure, I get that. Metrics for impact here, as in many social/philanthropic endeavors, are hard to come by.

You're right about the leadership issue, it's one that has plagued the climate conversation ever since Al Gore fell off. Yale Climate has a somewhat old article on this [0], where you may find guidance.

Bottom line is you don't have to believe me. If you're looking for a modern scientist-leader, listen to Dr. Katharine Hayhoe's TED talk ("The most important thing you can do to fight climate change: talk about it" [1]).

[0]: https://www.yaleclimateconnections.org/2012/03/whose-is-the-... [1]: https://youtu.be/-BvcToPZCLI

First thing is to bother your politician. I wrote a rather disturbing email to my MP, for which I got an acknowledgement that she would go and look at the IPCC reports. A few relevant facts like >100 million barrels of oil consumed daily, human emission of CO2 in gigatons, and the possibility that we're already past tipping point. It was polite but really not a nice thing to read.

I do phone up product suppliers and ask them why they've overdone the packaging but if it's only me they will ignore me. I've bothered BP over their environmental damage in Africa, and much more. I'll continue to do more but in the end I despair because 90% of people don't care.

Were it not for health problems I'd be out in central london getting arrested with the other 1,000 or so arrests in the past few weeks.

So there's answers. But I've been talking about this, and doing stuff about it, for ~20 years and no-one gave a shit. Now it may be too late. So do as you please.