Overshooting 1.5°C is risky – that’s why we need to hedge our bets

Further warming hugely increases the risk we will pass climate tipping points, such as the collapse of Greenland's ice sheet. Michal Balada / shutterstock

The global response to climate change has gained momentum since the 2015 Paris agreement, yet it remains inadequate to meet the scale of the challenge. That agreement established the goal of holding global warming to well below 2°C, and to pursue efforts to limit it to 1.5°C. To achieve this, greenhouse gas emissions should peak and decline as soon as possible.

The latest reports of the UN Environment Programme, the International Energy Agency and others have suggested that we are on the cusp of global emissions peaking. However, halting the increase in annual emissions is only the first step. Failure to act earlier and more decisively to bring emissions down to net zero has made limiting global warming to 1.5°C an uncomfortably close call.