Depends on where you live and your situation. You either limit your personal CO2 or the society's CO2 or even both. Most of my suggestions will make or save you money over time.
For personal you could do these, most of these will pay themselves back within 10 years in savings.
Swap gas stove for induction stove
Swap a gas boiler to heat pump + electric boiler
Buy solar panels for the roof and/or battery
Heat pump for domestic heating for colder regions.
Home insulation such as triple glass windows
For hot regions getting an awning for the windows facing the sun goes a long way.
Selling car to buy EV (CO2 neutral at 1 year, less CO2 after that)
Buying an E-bike if you have short trips and would like to bike more (CO2 negative almost instantly if you prevent car trips)
Otherwise if you don't feel like any of those investing in solar companies or battery production companies will make it easier for them to finance expansions to their operations and maybe even make you some money along the way.
If you live in the UK or applicable countries getting in on Octopus energy co-op energy production is a good way to invest the money and reduce CO2 at the same time.
Don't forget that an easy way to limit your carbon footprint is free. Notably plastics, aluminum, steel, other metals, concrete and beef.
To limit society's footprint you can show up to city Council meetings and advocate for bike paths and public transport which really goes a long way. Showing up with a couple of buddies, making them talk and buying beer for them after in one of the most cost effective ways to stop climate change. Often city council members just need some people to back them up when proposing the CO2 negative urban planning improvements.
Stopping climate change is all about taking small steps towards the solution, asking this question on lemmy is a great start.
You're not personally responsible or able to prevent climate change. This is a societal issue that requires societal changes. Don't feel obligated to put yourself in financial trouble since the impact to your life is potentially devastating and your impact to solving climate change would be negligible. It fucking sucks but we live in a brutal capitalist system and you need to make sure you can care for yourself.
I might suggest seeing if there are local advocacy groups where you can contribute your time and, if you truly have excess wealth, help with direct financial support as needed, small contributions to things like mailing campaigns or buying a booth at a faire will help much more than blanket contributions - but, IMO, the bigger need is in effort and time.
Considering we live in a conflicted world where capitalism has ruined everything, I'd say donate a few thousand of it around, but also save it and just make the right choices on what you buy:
buy zero waste, local and bio
buy fair and repairable phones
buy fair and ecological clothing
etc..
So many people don't realize that every time they buy something in a store, they are casting a little capitalistic vote. We have to speak the language of what these evil sons of bitches speak, money. So I think for individuals, it mostly starts with us.
Use it to free your own time to plant trees or contribute in another way. Spending 10k isn't gonna reduce climate change, but being able to work on the problem yourself will.
Buy the cheapest viable land you can and build an Earthship home out of tires, cans, bottles, and compressed Earth. Take yourself off the grid as much as possible.
I'd also suggest a career in or adjacent to alternative energy.
If you have any natural gas appliances in your home (like water heater, dryer, stove, oven, HVAC), transition to an electric version. Cancel your gas service.
Give it to a group like Just Stop Oil or other direct action / sabotage focused climate activism group - they're perpetually broke and could do a lot of good with that money.
As I havent seen a single actually effective answer:
Donate it to organisations fighting climate change.
For example FCA (researching climate friendly ways of producing cement, steel, fuels), gfi (researching food alternatives), CATF (tries to influence political changes)
I agree with the other guy, get yourself some solar panels and make yourself climate friendly, or even look at other ways you yourself an change in order to be carbon neutral
Aside from solar panels, as others have mentioned, I have a few other suggestions for things to get/do:
Hydroponic garden
Sewing machine
Heat pump water heater
Heat pump a/c
Induction stovetop
Upgrade insulation
Compost bin
Tools to repair common items
Promote the use of libraries and support their growth into other communal resources
Only buy things when needed
As others have said, there isn't much that a single individual can do against climate change, but let me explain my suggestions. Some of the most carbon intensive activities include the transportation of items like food, clothes, and other goods. To reduce your impact, you need to reduce your reliance on this carbon intensive logistics network. By growing your own food, learning to repair what you own, and learning to sew, you're making a large impact on your personal contribution to climate change. By supporting the library, you're encouraging the use of a shared pool of communal resources, which also reduces your community's climate impact.
The other items are what you can do to improve the efficiency of your house, if you own it. Induction stoves are incredibly safe and a highly efficient cooking surface. Heat pumps are crazy efficient at both heating and cooling, so slowly replacing old appliances with high efficiency options as they fail will maximize the use of what you own before it gets replaced. Compost bins and insulation certainly aren't glamorous like the other tech options, but they'll also go a long way: Landfills create an anaerobic environment, meaning food that gets thrown end up producing methane, and single family homes consume a lot of energy because heat escapes from every wall open to the air.
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.
While this isn’t a suggestion, just want to say don’t let other people saying one person doesn’t make a difference discourage you from doing what you can anyway.
“What is any ocean but a multitude of drops”? If a million people each don’t bother because they alone don’t make a difference?
Aid education. Lots of illiterate youth is going to be a problem when they can’t even read to research on their own.
Encourage increasing plant-based agriculture and the reduction of animal agriculture. Animal agriculture is terrible for the environment, and ironically the “green” version of it is even worse for the environment than factory farming if it were done to scale with the same product output. (Hunting is also not good to promote as an alternative, because if we hunted as much as we eat we would absolutely cause mass extinction very fast.)
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.
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.
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.
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.
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.
I've heard a statistic that goes something like: If you were to just not exist, you would only save about 1 second worth of emissions globally. Whatever individual action you do to reduce emissions from your lifestyle only go so far.
And like others have mentioned, there are the other, less legal forms of direct action.
Fund a sterilization program for young people who have come to understand the future that humanity is hurtling towards, and who want to avoid bringing a child into such a brutally cruel future.
Both my niece and nephew have sworn off of children, as they have good educations and have fully understood just how badly humanity is fucking itself over. They’re just trying to find doctors that will do those procedures on people under 30.
I'd probably donate it to the Thorium guys. Either the ones that just built the reactor research lab in Texas, or the shipyard ones. If coal becomes economically obsolete, the gigatons of CO2 will drop off like a rock.
Start a fund raiser, do advertisement, (make some donations your self so that it does not look dead) - ones you get a lot of money (lets say you have doubled) - start again and repeat until you double - within 10 cycles of doublings, you reach 10 million, and keep doing until you get rich enough (lets say 10 more cycles to reach 10B) then you have 2 paths to choose - either be a hero and actual invest in research and actively reversing shit done, maybe helping displaced or other good deeds, or the mlm path, and continue the doubling cycle, keep earning - with this much money, you can now have actors and fake donations, maybe even fake researches into how you are helping, and keep growing your wealth, and maybe then escape to a tax heaven.
Apologies for the dystopian ending, but realistically a person even going full carbon negative is not even a dent. If you actually want to do good, then you realistically require trillions, and then you feed that money to politicians, and reverse launder your way towards actual green solutions.