Climate disaster with 2°C of warming could be avoided if global pledges are met

If fully implemented, current climate pledges will keep global warming below the 2°C Paris Agreement limit, according to a study published today.

In 2015, the landmark Paris Agreement set a common goal for global climate action.

A total of 196 countries signed up, agreeing to limit global temperature increase to well below 2°C by 2100 and to 1.5°C if possible. Since 2015, signatory countries have made a range of national pledges to meet these targets.

According to the Intergovernmental Panel on Climate Change, if average global warming does exceed 2°C, the world will likely experience much more severe impacts including extreme heatwaves, droughts and water stress.

Published in the journal Nature Climate Change and including several researchers from Imperial College London, the study is the most comprehensive analysis of climate change pledges to date.

The study looked at countries that have announced or adopted net-zero commitments by June 2022, representing 70% of global carbon emissions.

‘Net-zero’ refers to achieving an overall balance between planet-warming greenhouse gas emissions produced and removed from the atmosphere.

Net-zero targets vary between countries. Both the European Union and the United States have committed to net-zero by 2050, while other major emitters have committed to later targets, including China who have committed to net-zero by 2060 and India by 2070.

The study found that if fully implemented, current net-zero commitments will be enough to keep global warming to around 1.7-1.8°C by 2100 – which would be  in line with the Paris Agreement’s “well below 2 °C” target, but not the more ambitious target of 1.5°C.

However, the authors caution that the pledges will only reach the target if they are fully implemented.

Projecting the pledges

Led by the Basque Centre for Climate Change, the study used four different modelling simulations to estimate the effectiveness of short-term and long-term pledges to limit global warming.

In addition to long-term net-zero targets, countries signed up to the Paris Agreement also have short-term targets to meet by 2030.

Analysis found that while many countries are making good progress to meet their short-term targets, there is an ‘ambition gap’ between short and long-term targets.

Dr Shivika Mittal, a contributing author of the study and researcher at Grantham Institute – Climate Change and the Environment at Imperial College London says that both ambition and action will be needed for countries to meet their long-term.

“As we approach the first Global Stocktake of the Paris Agreement, we have to face the fact that at a global level we aren’t doing nearly enough to get on track towards net-zero. Now is the time to walk the talk and rapidly implement the pledges.”

The modelling produced potential pathways for each country to meet their long-term targets and found that countries will face a range of challenges.  

These include the need for people to change their behaviours, land and water availability to grow crops for bioenergy and storing carbon, and making sure carbon-intensive infrastructure  such as power plants and industrial manufacturing facilities are replaced with low-carbon assets as soon as possible.

Dr. Alexandros Nikas, Senior Researcher at the National Technical University of Athens and one of the authors of the study, says that the study shows that “there is no one-size-fits-all policy or technological approach to ensuring that the Paris Agreement goal is kept alive around the globe.”

The researchers state five key actions that are needed to reach net-zero: decarbonise electricity, electrify transport, electrify heating, decarbonise industry and increase energy efficiency.

The clock is ticking

Today’s study comes just a day after sobering research from the World Meteorological Organisation estimating that there is a high chance that the world will experience 1.5°C of warming by 2027.

In another study published yesterday, World Weather Attribution found the mid-April heatwave that impacted Bangladesh, India, Thailand and Laos was made 30 times more likely because of climate change.

It is now clearer than ever before that climate change is impacting millions of people around the world today.

Dr Ajay Gambhir, a researcher at the Grantham Institute – Climate Change and Environment at Imperial College London and one of the authors of the climate pledges study, hopes the research will accelerate climate action.

“Scientists are sometimes accused of being too conservative in their analysis of climate change and the requisite actions to tackle it.

“We want our analysis to be part of a body of evidence that is used to remind politicians, businesses and civil society as loudly as possible that the goals of the Paris Agreement – one of the most critical international treaties in existence, designed to avoid a climate disaster – will be missed unless mitigation is vastly accelerated.”