The industrialized world has been spewing carbon dioxide and other greenhouse gases faster than they can be contained for centuries. Climate change, and the increasing frustration of citizens about the inadequate response, is pushing countries to take action, or at least say they will. Becoming carbon neutral -- also known as climate-neutral or net zero -- is now a legal requirement in some countries, while European authorities are preparing legislation to become the first net zero continent. Even oil companies are getting in on the act.

1. What is carbon neutral?

It means cutting emissions to the very limit and compensating for what can’t be eliminated. Countries, for example, can spur the use of cleaner autos, transition economies away from carbon-intensive heavy manufacturing and switch to greener sources of electricity such as wind and solar. Companies can adjust their practices, so a data center operator might switch to renewable power or an airline might invest in reforestation to offset pollutants from their jets.

2. How can polluters compensate?

They can purchase carbon “offset” credits. Developed by the United Nations and non-profit groups, these let the owners emit a specified amount of greenhouse gas, and that is offset by funding carbon-reduction projects such as reforestation. There’s also an effort to harness existing markets that trade pollution permits to provide a similar mechanism. Carbon offsetting has spiked in the past year as more companies adopt the approach.

3. Who’s trying to be carbon neutral?

Dozens of countries have commited to go net-zero, or at least out-perform carbon-reduction targets set out in the landmark 2015 Paris Agreement on climate change. (U.S. President Donald Trump plans to withdraw from the Paris accord.) In June, the U.K. and France became the first major economies to pass legislation requiring net-zero carbon emissions by 2050. The European Union is proposing to completely overhaul its economy to achieve the same goal. Dozens of global cities and companies have announced carbon-neutral initiatives, with Spain’s Repsol SA the first oil major to target carbon neutrality. Buildings, airlines and even events have made the pledge, while investments groups managing almost $4 trillion of assets have committed to having carbon neutral portfolios by 2050.

4. What’s driving this?

Climate experts blame the vast build-up in atmospheric CO2 and other greenhouse gases since the Industrial Revolution for speeding up global warming. Without radical measures to reduce emissions, scientists warn that the fight against climate change will become unwinnable. CO2 pollution is still rising -- 2019 will be another record -- and is unlikely to peak before 2040, driven by growing use of fossil fuels, says the International Energy Agency.

5. How will the goals be reached?

More urgent government action is needed to trigger changes in transport, infrastructure, land use and how cities are built. To get anywhere close to net zero by 2050, the world must invest $2.4 trillion in clean energy every year through 2035, according to the UN’s Intergovernmental Panel on Climate Change. That compares with $1.8 trillion spent in 2017 on all forms of energy systems. Coal should also be phased out almost entirely by mid-century, the panel says. Europe’s plan envisions additional investment on energy and infrastructure of as much as 290 billion euros ($320 billion) a year after 2030. Individuals are increasingly able to take more control; the market for consumer offsetting is flourishing albeit with doubts over the effectiveness of some methods. One promising strategy, still unproven on an industrial scale, is to trap CO2 from polluters before it enters the atmosphere and bottle it up in giant underground cavities -- a technology known as carbon capture. Other new technologies include using hydrogen as a fuel.

6. Who’s policing the rules?

Nobody really. There is some oversight built into the Paris Agreement that holds countries accountable if their climate plans aren’t ambitious enough, but nothing is enforceable by law at a global level. So far, scientists, protesters, NGOs and investors have been the main source of pressure on countries to change and make sure their promises are kept. As well as countries, a growing number of U.S. states have enshrined their commitments into legislation, making pledges harder to break.

7. Is this all just talk?

That’s the big question. Any country can make its carbon footprint appear smaller by shifting the burden -- winding down polluting industries at home but buying those products elsewhere. Carbon offset programs are also fallible, since there’s no mechanism to guarantee purchases are legitimate. And lawmakers can make ambitious pledges in the knowledge they’ll be out of office before any deadlines hit. Skeptics call environmental promises rolled out for the sake of good publicity “greenwashing.” Still, public opinion is shifting in many parts of the world, evidenced by a global wave of protests, and politicians are taking note.

To contact the reporter on this story: Jeremy Hodges in London at jhodges17@bloomberg.net

To contact the editors responsible for this story: Reed Landberg at landberg@bloomberg.net, Andy Reinhardt, Grant Clark

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