The Paris Climate Agreement requires us to move towards carbon neutrality, but what does reducing net greenhouse gas emissions to zero actually mean? Simply put, net-zero emissions refers to achieving an overall balance between greenhouse gas emissions released and absorbed. According to IPCC (Intergovernmental Panel on Climate Change), carbon neutrality is achieved when GHGs emitted by human activities are equal to those removed from the atmosphere within a certain period of time. This is why we use the terms “net-zero” or “zeroing net emissions”. For a visual perspective, think of it like a set of scales– producing greenhouse gas emissions tips the scales, whereas removing or offsetting the same amount of emissions can restore the balance. To maintain this equilibrium, no more greenhouse gasses can be added to the atmosphere in any given year than is taken out or absorbed, from trees and oceans for instance.
Getting to net-zero means we can still produce some emissions, as long as they are offset by processes that reduce greenhouse gasses already in the atmosphere. For example, these could be things like planting new forests, or drawdown technologies like direct air capture. The more emissions that are produced, the more carbon dioxide we need to remove from the atmosphere to reach net-zero.
Climate change isn’t a faucet we can turn off once we stop using fossil fuels. Carbon dioxide, the main contributor to climate change, will stay in the atmosphere and keep heating the planet for decades. In order to avert the worst impacts of climate change and preserve a livable planet, global temperature increase needs to be limited to 1.5°C above pre-industrial levels. Currently, the Earth is already about 1.1°C warmer than it was in the late 1800s, and emissions continue to rise. To keep global warming to no more than 1.5°C – as called for in the Paris Agreement – emissions need to be reduced by 45% by 2030 and reach net-zero by 2050.
Transitioning to a net-zero world is one of the greatest challenges humankind has faced. It calls for nothing less than a complete transformation of how we produce, consume, and move about. The energy sector is the source of around three-quarters of greenhouse gas emissions today, and holds the key to averting the worst effects of climate change. Replacing polluting coal, gas and oil-fired power with energy from renewable sources, such as wind or solar, would dramatically reduce carbon emissions.
IPCC demonstrates in its recent report that net emissions must be reduced to zero in order to stabilize global temperatures. The report also states that any scenario that does not involve a reduction to zero will not stop climate change.
Governments and companies worldwide are pledging to achieve net-zero emissions of greenhouse gasses. More than 70 countries, including the biggest polluters – China, the United States, and the European Union, have set a net-zero target, covering about 76% of global emissions. Over 1,200 companies have put in place science-based targets in line with net-zero, and more than 1000 cities, over 1000 educational institutions, and over 400 financial institutions have joined the Race to Zero, pledging to take rigorous, immediate action to halve global emissions by 2030.
We’re not quite on track at the moment, according to the United Nations Environment Program (UNEP). In 2020, the pandemic caused greenhouse gas (GHG) emissions to drop by 7 per cent compared to the previous year. While this figure is unprecedented in and of itself, in the long run it may become practically irrelevant as we need to cut global emissions by a further 7.6 percent each year for the entire decade 2020-2030.
Current national climate plans – for all 193 Parties to the Paris Agreement taken together – would lead to a sizable increase of almost 14% in global greenhouse gas emissions by 2030, compared to 2010 levels. Getting to net-zero requires all governments to significantly strengthen their Nationally Determined Contributions (NDCs) and take bold, immediate steps towards reducing emissions now. The Glasgow Climate Pact called on all countries to revisit and strengthen the 2030 targets in their NDCs by the end of 2022, to align with the Paris Agreement temperature goal.