10k will not do much good on the grand scale of things. Once you start involving other people directly, the costs start skyrocketing. Be it if you want to bribe politicians, fund a revolution, invest into sustainable tech or just creating a bottle cap recycling programme, 10k just isnt gonna get you far enough. So focus on your own climate impact. I think the absolute best you could do for the most positive net good is to take inventory of your own carbon emissions and replace or upgrade whatever you need to lower them. Lower your heating usage by getting a heat pump instead of burning coal for example. This will depend on how low your carbon output currently is though.

Climate change is tied to capitalism. Use it to run for office.

Invest it into a mutual fund fighting climate change. My bank has one. I guess many banks do. Some relevant terms in their fund names: fossil-free, climate, forest, sustainable agriculture.

Several funds in my bank have ESG in the name.
https://en.wikipedia.org/wiki/Environmental,_social,_and_governance

As a few people have said, buying something like solar panels, or the deposit on an electric car would probably be the best - reducing your impact is probably the most you can do.

The other option could be green investment.... They do exist, ignore 'transitional energy' funds (90% oil majors), look at the individual shares that any fund that looks interesting. I have some money in EdenTree funds. That way your money is hopefully helping do good, while (hopefully) growing so you can do something that will have a bigger personal effect.

Your time and energy is far more valuable than your money.

I would recommend using that money as an emergency fund, and getting involved with an activist organization working to stop climate change. There are a wide range of them, with tactics ranging from legislative pressure to property destruction and civil disobedience. Believe it or not, there are lots of small local problems that a small group can meaningfully impact, and will add up.

While there are systemic problems that cannot be solved by an individual, they can be solved by collective organization. You have to be part of that collective if you want to stop climate change.

Spending and consumning less could help more. Espicially gas and meat.

Well, a certain cadre of income is responsible for the lion's share of western emissions. Maybe you could use that money to "influence" them.

https://en.m.wikipedia.org/wiki/List_of_oil_pipelines

https://www.militarynewbie.com/wp-content/uploads/2013/11/TM-21-210-Improvised-Munitions-Handbook-1969-Department-of-the-Army.pdf

Its a drop in the ocean and I'm going to come off negative here but your up against jets, deliveries on demand from across the globe, mass meat industry and oil companies that will lobby against their destruction and in tern for mass extinction. If you really want to fight climate change move somewhere that won't see the effects, install solar learn to live off the land. An alternative if not too late become a revolutionary topple capitalism the system that allowed us to get to this point and beyond.

Send it to me, I’ll grow some trees and hemp and shit.

Put that money in stocks or ETFs that align with your climate goals. You don’t even have to dig too deep to find ones that meet your needs. Much digital ink has been spilled on the topic. Just find one or two you like and go for it.

In a general sense, put the money where you want change to happen in this version of reality.

Children of Kali

Fund journalism and media against fossil fuel

Put it in a bank that doesn't invest your money into the wrong stuff. In fact a bank can loan more money than it has, but there's a ratio set by law. So for example that could effectively be 30k in arbitrary investments.

If you want to spend it, I'd buy a good bicycle or get my home isolated or sum like that. You could get cooking lessons and proper cookware and stay away from processed foods that generate tons of waste. If you have the space you could grow your own vegetables and have chickens, which eat bio waste. Basically reduce what you buy. You could get tools and learn how to fix things if that's more up your alley. For example I've fixed my Sennheiser headphones several times, but it did need some investment in tools. You could also donate it to a repair café.

Plant a fuckload of protected species trees