The carbon clock is ticking: Why and how reach net-zero emissions?
By: Samuel Bühlmann
Tags: Net Zero Emission, Global Warming, Climate Action, Carbon Emissions, Carbon Budget

The climate clock displays 7 years 40 days as of today. This is the time we have left to achieve net-zero emissions and take all man-​made greenhouse gasses back from the atmosphere thereafter.

Only little time is left to prevent irreversible damages.

Let’s explore what net-zero emissions are, why they are important and how organizations think about achieving them. This article in bullet points:

Our atmosphere can absorb another 301 Gt of CO2 before we can no longer limit global warming to 1.5°C. At current emission levels we’ll be there in 7 years.

To limit global warming to 2°C the budget is at 1’051 Gt of CO2. At current emission levels we have 25 years left to exhaust it.

1.5°C or 2°C, 7 or 25 years — it will get warmer in any case, but the differences in consequences can be dramatic and if we cross the budget we risk famines, streams of refugees and conflicts.

More and more countries, cities and companies are now announcing their climate targets to become carbon neutral or reach net-zero emissions.

Carbon neutral is compensating by funding CO2 reduction elsewhere (offsetting) and net-zero is funding the removal through negative emission technologies.

To reduce the carbon footprint, organizations often divide emissions into scopes: 1, 2 (reducing emissions from direct operations and energy sources) and 3 (reducing emissions in the value chain).

The bucket is almost full. According to the MCC in 2017 we had another 420 Gt of CO2 to pump into the atmosphere to stay on track with limiting global warming to 1.5°C. With annual global CO2-emissions of ~40 Gt we are now at 301 Gt and have, as mentioned, about 7 years to exhaust the remaining carbon budget . The global carbon project is a bit more optimistic. In their 2019 conclusion we have 9% of the budget left and another 10 years at current emissions as shown in the following graph.

Only 9 % of the carbon budget is left. (Global Carbon Project, 2019)

The more emissions are stored in the atmosphere, the longer it takes for them to be removed again (more on space and volume in a future issue). For now we are still filling up the bucket, where in theory we should be reducing CO2-emissions drastically to stop climate change, stabilize global temperature and prevent irreversible climate damages. What are these damages? Relative to the achievement of the temperature targets, here are examples of three scenarios for 2050:

Target 1.5°C achieved: The world would still be hotter than it is now. Target 2°C achieved: Developed nations would have constructed storm-surge barriers to keep out the sea and erected border walls to keep out refugees. And according to the World Resources Institute, the difference between reaching the 1.5°C or 2°C target will be quite dramatic. Targets failed: On top of the previous consequences, global warming could produce conflict, within and between poor and rich nations.

Society, politics and businesses seem to have understood the situation. Countries, cities and companies are announcing their climate targets. “We aim to have CO2 emissions peak before 2030 and achieve carbon neutrality before 2060” said China’s President Xi Jinping just recently. In January, Microsoft announced it would be carbon-negative in 2030, meaning from then on it will remove more CO2 than it will produce and thereby neutralize all direct and electricity emissions since it was founded 1975 by 2050. Companies from all industries are joining forces to save the planet. Even multinational oil and gas company BP declared its ambition to become a net-zero company by 2050. So far, over 1000 companies have signed the Science Based Target initiative and even more have joined the We Mean Business Coalition.