Name: What is net zero? | The Economist（What is net zero? | The Economist）
Uploaded: 2021-10-04T20:36:45.000Z
Duration: 7 min 22 s
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Companies from British Airways to Facebook...

...and pop artists like Billie Eilish and Massive Attack...

...to bring their greenhouse-gas emissions closer to net zero

They're joining a club of more than 50 countries around the world

This race to zero is a vital step towards managing climate change

But like all simple slogans, the reality of achieving it...

...has resulted in more carbon dioxide in the atmosphere...

...the level of greenhouse gases in the atmosphere has to stop rising

The obvious way to do that is to stop emitting them

For some industries such as aviation and manufacturing...

In the years leading up to the Copenhagen climate conference in 2009...

...it wasn't possible to cut emissions fast and thoroughly enough...

...to meet the temperature targets that policymakers wanted

...was to actively remove greenhouse gases from the atmosphere too

People began to talk about a world in which greenhouse-gas emissions...

...and greenhouse-gas removals balanced each other out

The countries that signed up to the Paris Agreement...

...pledged to turn this idea into reality, by agreeing to balance their...

...emissions and removal of greenhouse gases...

To achieve net-zero emissions, we need to do two things...

..is to cut our output of greenhouse-gas emissions...

But the other is actually to take emissions out of the air

And that's the harder and sometimes more obscure aspect...

And the scale in which they might be required...

...is one reason that net-zero targets will be hard to achieve

We'll need to go from a world economy that pumps out on the order...

...of 40 billion tonnes of CO2 a year to one that sucks down...

...that is, removes billions of tonnes per year in the future...

There's different ways to do this, forests do this naturally...

...to achieve ambitious climate targets are man-made approaches

Some methods for removing greenhouse gases from the atmosphere...

...are already being used at scale, such as the planting of new forests

And improving soil so it can store more carbon

But there are new technologies at a much earlier stage of development

Among them ways of capturing carbon dioxide...

Carbon dioxide could be pulled directly from the air by machines...

...burning them to generate electricity...

...and then capturing the carbon dioxide as they burn

There's a flurry of innovation in negative-emissions technologies

A range of ambitious to wacky, and none of them are proven at scale

And that's what makes them so problematic

...that have not yet been demonstrated at scale...

...to achieve targets that we're setting for ourselves

We're hopeful, but it is still a risky bet

How much greenhouse gas needs to be removed...

...will depend on how much emissions can be cut

...as well as a dramatic scale up and proving...

...of the technologies for negative emissions

...and it's easy for governments and industries...

...to kick the can down the road saying, well...

...let's go a little slower on the cutting of emissions now...

...which will be better for the economy or for our profits...

...because we can always make massive negative-emissions reductions...

...later when innovation makes those technologies...

The dirty little secret in that argument...

...is that it may come too late and it may well give permission...

...for polluters to get away with polluting much more than need be...

...rather than innovating ways to reduce emissions now

There's also the question of who takes responsibility...

...is that lots of countries and companies and individuals...

...don't want to own up to their carbon footprint

For example, carbon-intensive countries like...

...India, China or other emerging markets...

...that are producing enormous amounts of emissions today

They point out that the goods they produce, for example...

...may be consumed by Americans or Europeans

So they should do the negative emissions or they may say...