Image copyright PA Image caption Protesters at a "die in" in Glasgow

The UK should lead the global fight against climate change by cutting greenhouse gases to nearly zero by 2050, a report says.

The Committee on Climate Change (CCC) maintains this can be done at no added cost from previous estimates.

Its report says that if other countries follow the UK, there’s a 50-50 chance of staying below the recommended 1.5C temperature rise by 2100.

A 1.5C rise is considered the threshold for dangerous climate change.

Some say the proposed 2050 target for near-zero emissions is too soft, but others will fear the goal could damage the UK's economy.

The CCC - the independent adviser to government on climate change - said it would not be able to hit “net zero“ emissions any sooner, but 2050 was still an extremely significant goal.

The main author Chris Stark told me: “This report would have been absolutely inconceivable just a few years ago. People would have laughed us out of court for suggesting that the target could be so high.”

The main change, he said, was the huge drop in the cost of renewable energy prompted by government policies to nurture solar and wind power.

He said the BBC's David Attenborough climate documentary, protests by Extinction Rebellion and speeches by the teenage campaigner Greta Thunberg had persuaded the public that the problem needed urgent action.

But Mr Stark said there was no way the 2050 target would be achieved unless the government backed it with policies and money.

He noted that the UK was already slipping away from a legal obligation to cut its emissions step-by-step between now and 2032.

Media playback is unsupported on your device Media caption Teen activist Greta Thunberg addresses Extinction Rebellion rally

The cost of the new proposal, the CCC estimates, is tens of billions of pounds a year and may reach to 1-2% of national wealth (as measured by GDP) each year by 2050. That doesn’t count the benefits of decarbonisation - such as cleaner air and water.

The CCC said England can eliminate emissions by 2050, while Scotland could go carbon-free sooner - by 2045. Scotland has exceptional potential for planting trees (which absorb carbon dioxide) and is more suited for carbon capture and storage.

Wales can only cut 95% of its emissions by 2050 because of its farm industry. Northern Ireland will follow England’s targets.

The government is studying the report, which has substantial implications for public finances, and says it "sets us on a path to become the first major economy to legislate to end our contribution to global warming entirely".

How do you reach zero emissions?

The plan is for “net zero“ emissions by 2050, which means balancing carbon emissions with carbon removal. In practice, we'll need to slash the amount of CO2 we put in the atmosphere.

Unavoidable emissions need to be captured and stored (for example, where CO2 is collected from a power station chimney and put underground) or offset by planting trees.

Until now, the target had been to reduce emissions by 80% compared with 1990 levels by 2050.

How this affects you

The CCC believes that achieving zero emissions depends on low-carbon technologies and changes to industry, and public behaviour.

Here are some of the report's recommendations for the public.

Home heating

The report has one controversial recommendation: to turn down the home thermostat to 19C in winter.

We will need to insulate our homes much better. Some of us will use heat pumps - a sort of reverse refrigeration technology that sucks warmth from the ground - and convert natural gas boilers to hydrogen ones.

The committee expects consumer bills to rise at first, then fall as a newer, cheaper electricity generators are introduced.

Flying

The aviation industry is trying to bring down the cost of making jet fuels from waste materials.

But the CCC says this won’t be enough. The number of flights we take is increasing, and the report predicts that government action will be needed to constrain the growth.

However, it doesn’t say how – and the committee chair, John Gummer, ducked a question about Heathrow expansion at the report's launch.

Cars

The report says we won't need to overhaul our motoring habits, but eventually we will be driving electric cars.

The government has set a target date of 2040 beyond which conventional car sales will be banned. However, the committee says that deadline should be 2030.

Meat

The committee notes many people are already eating less red meat for the health of the planet and themselves.

It says people can reduce their diet-related emissions by 35% if they transition from a high-meat diet to a low-meat one. But it only predicts a 20% drop in meat consumption by 2050.

Waste

Bio-degradable waste should not be sent to landfill after 2025. This means we would all be obliged to separate our food waste from other rubbish. The report recommends reducing food waste as far as possible.

What else can I do?

Media playback is unsupported on your device Media caption Strangers are sharing unwanted food in a bid to save money and reduce food waste.

The CCC says people can also take the following steps:

Choosing to walk, cycle or take public transport

Choosing LED light-bulbs and electric appliances with high energy efficiency ratings

Setting the water temperature in their heating systems to no higher than 55C

Using only peat-free compost

Choosing quality products that last longer and sharing rather than buying items, like power tools, that are used infrequently

Checking your pension funds and ISAs to see if your investments support low-carbon industries

Which businesses and sectors would be affected?

The big push is to decarbonise industry and heat generation. Carbon capture technology will be needed on many of the major emitters: the steel, paper, aluminium and paper industries.

Image copyright Getty Images Image caption Farmers would need to find ways to reduce methane emissions from cows

Agriculture is a major emitter of greenhouse gases through sheep and cattle burping methane, and from fertilisers.

Farmers would need to reduce the amount of land in pasture, increase woodland, and feed cattle food that creates less methane gas.

The fracking industry would also be affected - the committee says we should only use fracked gas in the UK if it replaces gas that would otherwise be imported.

What's been the response?

Environmental groups are supportive - although many think 2050 is too conservative.

The UK Health Alliance on Climate Change has called on the government to adopt the recommendations but "adopt a net-zero target before 2050".

Lorna Greenwood of Extinction Rebellion told me: "2050 condemns us to a bleak future... Others are already dying round the world thanks to inaction and far-off target setting."

The environmental campaign group WWF has said: “The problem is, we’ve been acting as if we have time. But if we want a world with coral reefs, safe coastal cities and enough food for everyone, we must act now."

Business and industry groups have expressed support but argue they need government help.

Rain Newton-Smith, chief economist at the Confederation of British Industry (CBI) said: “The UK should do all it can to mitigate the worst impacts of climate change. What we need now is a supportive and timely response from the government to enact this ambitious target."

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Meanwhile, Minette Batters, president of the farm union NFU, told me: “We take the climate issue very seriously. With Brexit and the government’s Agriculture Bill the government can shift farm support towards helping farmers reduce greenhouse gas emissions.”

Meanwhile, Dr Shaun Fitzgerald, director of The Royal Institution, said: “I am a massive supporter of efforts to reduce greenhouse gas emissions.

But he added: "Will people be prepared to set their winter time thermostat to 19C? Asking people to put up with a reduction in comfort/quality is going to be difficult."

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