Why has the UK introduced a net zero target on greenhouse gas emissions?

The UK has become the first major economy to set a net zero target on greenhouse gas emissions for 2050.

– What has happened?

The Government has signed into law a new target to cut greenhouse gas emissions to “net zero” by 2050, after it was approved by the Commons and Lords this week.

It strengthens the target the UK already had to cut its greenhouse gases by 80% on 1990 levels by mid century, which was approved by MPs under the Climate Change Act in 2008.

– Why do we need to aim for zero emissions?

As more greenhouse gases lead to more warming, stabilising the planet’s temperature at any level will require global emissions to fall to zero overall.

A key UN report last year said that to keep temperatures from rising to more than 1.5C (2.7F) in the long-term, countries need to cut carbon emissions to net zero by 2050, with steep cuts in other greenhouse gases such as methane.

– What does net zero mean?

It means cutting emissions to as close to zero as possible and using methods to take greenhouse gases out of the atmosphere to “offset” the remaining pollution – for example, by planting trees which absorb carbon dioxide.

– What happens if we do not do it?

We have already experienced 1C (1.8F) of warming, and commitments by countries to cut their emissions leave the world on track for rises of 3C (5.4F) by 2100.

Temperature rises of more than 1.5C are set to increase extreme weather events such as heatwaves and flooding, cause greater losses in crop yields and wildlife and raise the risk of large-scale irreversible impacts such as melting ice sheets which will push up sea levels.

– We are just one country. How much of a role can the UK play?

While the UK’s current emissions make up only a small percentage of the overall global output, the country led the industrial revolution and has made a major contribution to greenhouse gas pollution over time.

Cutting all greenhouse gas emissions to net zero by 2050 will meet the UK’s commitments under the Paris Agreement to limit global warming and provide leadership for other countries to follow suit.

– How are we doing so far?

The Government is keen to point out that we have already cut emissions by 42% on 1990 levels, which is largely as a result of reducing pollution from generating electricity with a switch away from coal and towards renewables.

But much less progress has been made in cutting pollution from heating homes and transport emissions have remained at virtually the same levels since 1990 – although electric vehicles are beginning to take off.

The UK is currently not on track to meet the interim reduction targets known as “carbon budgets” set for the mid 2020s and early 2030s.

– Can we do it?

The Government’s advisory Committee on Climate Change concluded it can be done with known technologies and within the expected economic cost that Parliament accepted when it set the current 2050 target for an 80% cut on 1990 levels.

But it will require “clear, stable and well-designed policies” to reduce emissions further across the economy without delay, the experts say.

And moving to a zero emissions economy must be fair on workers and consumers.

– What will it involve?

Phasing out greenhouse gases over the next three decades will require changes in all areas of the economy, including more low-carbon power, electric vehicles, tackling emissions from aviation and industry and changes to how land is used and buildings are heated.

The Government has said it will retain its ability to use international carbon credits to meet the goal, which pay to offset emissions with reductions elsewhere in the world – a loophole campaigners want to see closed.

– What can people do in their own lives to reduce emissions?

Active engagement from households to reduce their carbon footprint will be vital to achieve net zero, the Committee on Climate Change has said.

People can choose to walk, cycle or take public transport or make their next car an electric one, and minimise flying.

They can improve the energy efficiency of their homes, as well as setting thermostats no higher than 19C (66.2F), and consider installing low-carbon heating systems.

Eating a healthy diet such as cutting down on beef, lamb and dairy can also help tackle emissions, as can reducing food waste, buying peat-free compost and sharing, rather than buying, items like power tools that are not often used.