Over the next 31 years, we're likely to be taking fewer flights, eating less meat, and using far less single-use plastic.
That is, if the UK government is to achieve its target of cutting greenhouse gas emissions to almost zero by 2050 - an ambitious plan that no other major nation has made.
The year 2050 might sound like a long time away - if in 2019 you're 25 like Stormzy and Harry Kane, you'll be 56 at the start of 2050.
Critics such as the Green Party say the "net zero" target could happen much sooner, while others say it is too ambitious and expensive.
So what does that target mean for you? And how could the world have changed by 2050?
How do you reach zero emissions?
The plan announced by Prime Minister Theresa May is based on a report by the Committee on Climate Change (CCC), which advises the government on environmental issues.
While today's announcement focuses on big-picture changes like investing in cleaner energy sources and planting trees, the CCC report includes lots of practical tips on how we can all fight climate change, like:
Eat less meat
By 2050, you could have bitten into your last chicken burger. Imagine it.
Lots of us are already cutting down on how much meat we eat, with millions of people taking on challenges like Meat Free Mondays and Veganuary.
The CCC says people can cut their diet-related emissions by 35% by switching from a high-meat diet to a low-meat one. However, it reckons the UK's meat consumption will only drop by 20% over the next 31 years.
Turn the heating down
Keeping your house as steamy as the Love Island hot tub costs money - and it affects the environment too.
Lots of the heating in our homes comes from natural gas, which releases harmful levels of carbon dioxide into the atmosphere.
The CCC says we should turn our thermostats down to 19C in order to cut the amount of energy used, as well as insulating them better.
Fly less often
Plane manufacturers are already trying to cut emissions by making jet fuels from waste materials.
But the CCC says that's not enough. We need to fly less.
So get used to having your holidays in Brighton rather than Barbados.
Cut down on waste
Takeaway coffee cups, single-use plastic bottles and excessive cosmetic packaging will all need to go if we're to achieve the 2050 target.
The CCC also says biodegradable waste shouldn't be sent to landfill after 2025. That means cutting down the amount of food we waste, and separating that waste from our other rubbish.
While Northern Ireland will follow England's target, Scotland has promised to hit net-zero emissions by 2045.
The CCC says Wales can only cut 95% of its emissions by 2050 because of its farm industry.
Life in 31 years' time
2050 is quite a long time away. What else could have happened by then?
There will be almost 10 billion people in the world, according to the United Nations. At the moment, there are just under 8 billion.
We reckon 56-year-old Stormzy will still be making sick music.
We'll have seen seven more FIFA World Cup competitions - both men's and women's.
England captains Harry Kane and Steph Houghton will be 56 and 61 respectively. Hopefully they'll have lifted a good few of those World Cups by then.
Our outgoing prime minister, Theresa May, is 62 now. She'll be 92 years old at the start of 2050.
Toilets will be equipped with "mini laboratories" that analyse the health of our poo, according to futurologist Ian Person.
You could have saved a huge… £7,950, if you start putting away £5 a week from now onwards. That's about the price of two takeaway coffees. Stop buying them and you'll help lessen plastic waste too - another bonus for the planet.
How are people responding to the government target?
"It would be easy to overlook this news," says Professor David Reay, an energy expert at University of Edinburgh. "We shouldn't. It's momentous."
"Achieving net zero by 2050 will change all our lives. It will transform the ways we travel, the homes we live in and the food we eat. It will reshape our towns, cities and countryside, delivering cleaner air and water alongside a safer climate for generations to come."
Some environmental campaigners feel less positive about the plan, however.
"It's a real shame the government hasn't had the courage of its convictions," says Caroline Lucas MP, former leader of the Green Party.
She thinks the UK could reach "net zero" more quickly. She's also criticised the government's plan to reassess the target after five years - which could allow it to change or even drop its target.
Liam McClelland, co-chair of Young Greens, the Green Party's youth division, argues that while the UK is the first to propose cutting carbon emissions by 2050, other countries have taken bold steps towards going carbon neutral.
"If a country the size of Canada can go single-use plastic-free by 2021, then why can't we?" he says.