Net zero emissions

Global net zero emissions describes the state where emissions of carbon dioxide due to human activities and removals of these gases are in balance over a given period. It is often called simply net zero.^[2] In some cases, emissions refers to emissions of all greenhouse gases, and in others it refers only to emissions of carbon dioxide (CO₂).^[2] To reach net zero targets requires actions to reduce emissions. One example would be by shifting from fossil fuel energy to sustainable energy sources. Organizations often offset their residual emissions by buying carbon credits.

People often use the terms net zero emissions, carbon neutrality, and climate neutrality with the same meaning.^{[3][4][5][6]: 22–24} However in some cases, these terms have different meanings from each other.^[3] For example, some standards for carbon neutral certification allow a lot of carbon offsetting. But net zero standards require reducing emissions to more than 90% and then only offsetting the remaining 10% or less to fall in line with 1.5°C targets.^[7]

In the last few years, net zero has become the main framework for climate action. Many countries and organizations are setting net zero targets.^[8][9] As of November 2023, around 145 countries had announced or are considering net zero targets, covering close to 90% of global emissions.^[10] They include some countries that were resistant to climate action in previous decades.^[11][9] Country-level net zero targets now cover 92% of global GDP, 88% of emissions and 89% of the world population.^[9] 65% of the largest 2,000 publicly traded companies by annual revenue^[9] have net zero targets. Among Fortune 500 companies the percentage is 63%.^[12][13] Company targets can result from both voluntary action and government regulation.

Net zero claims vary enormously in how credible they are, but most have low credibility despite the increasing number of commitments and targets.^[14] While 61% of global carbon dioxide emissions are covered by some sort of net zero target, credible targets cover only 7% of emissions. This low credibility reflects a lack of binding regulation. It is also due to the need for continued innovation and investment to make decarbonization possible.^[15]

To date, 27 countries have enacted domestic net zero legislation. These are laws that legislatures have passed which contain net zero targets or equivalent.^[16] There is currently no national regulation in place that legally requires companies based in that country to achieve net zero. Several countries, for example Switzerland, are developing such legislation.^[17]