All too often, people delve into the detail of net-zero before looking at the bigger picture and how net-zero target setting began.

Ever since COP21, better known as the Paris Climate Change Agreement in 2016, we have seen many businesses and countries committing to reduce their emissions and announcing net-zero target dates. This has been incredibly encouraging, but it is also important that these targets are both robust and ambitious (something we will come onto later in our net-zero insights series).

The message from COP21 in Paris and from the IPCC since then has been crystal clear. The science on climate change is telling us that we must rapidly reduce greenhouse gas emissions globally by 45% by 2030 and to net-zero by 2050. If we do not do this, we have no chance of keeping global warming to within 1.5°C.

The significance of 1.5°C

This 1.5°C figure is vitally important. It is a figure that is often used but not always understood. If the average global temperature increases by more than 1.5°C from pre-industrial levels (set at an 1850-1900 average baseline), then we will see increasingly catastrophic consequences of climate change. Even at 1.5°C warming we will see significant impacts on our planet. If we exceed this target by just half a degree, the results will be dramatic: ice-free arctic summers will increase 10-fold, double the number of vertebrates and plants will lose their habitats, as will triple the number of insects¹. We will lose a shocking 99% of our coral reefs and almost 40% of the global population will be exposed to extreme heat at least once every five years.

These are significant impacts and we must act now if we are to avoid them. Worryingly, we have already seen an average increase in temperatures of 1.1°C. These increases in temperature are directly related to the amount of carbon and other greenhouse gasses (GHGs) that humans emit into the atmosphere. It is these GHG emissions that we must reduce by 45% by 2030 and to net-zero by 2050, at the latest.

What does net-zero actually mean?

Net-zero emissions are achieved when anthropogenic emissions of greenhouse gases to the atmosphere are balanced by anthropogenic removals over a period of time².

Put more simply, what goes up must come down. However, what is often missed when looking at net-zero is that it is not as simple as balancing carbon emissions with carbon removals/offsets. Robust methodologies for achieving net-zero (again, something we will come to later in our net-zero insights series) require significant reductions in absolute emissions (up to 95%) before balancing out the rest with removals/offsets. We need rapid and deep decarbonisation, not just the balancing of emissions.

It can be easy to feel down when we look at figures on carbon emissions and the impacts of climate change. However, there are real reasons to be optimistic, and throughout this series of insights we hope to shine light on the positive solutions required to create a brighter, sustainable future for all.

In May we will cover how to approach setting a robust net-zero target. To receive the next insight in this net-zero series, as well as other insights on ESG and sustainability, sign up to our newsletter at the bottom of this page.

Author: Henry Unwin, Head of Carbon and Climate Services

1. wri.org
2. ipcc.ch