Understanding the Paris Agreement and the 1.5C Climate Threshold
Global efforts to curb warming face critical challenges as temperature targets remain under pressure.
1The 2015 Paris Framework
In 2015, nearly 200 nations signed the Paris Agreement to limit global warming to 1.5C above pre-industrial levels. This landmark deal mandates that countries set individual emission-reduction targets, reviewed every five years to increase ambition. It aims to achieve net-zero emissions in the second half of this century through international cooperation.
2Defining the 1.5C Target
The 1.5C threshold refers to a 20-year average rather than a single year's temperature. While 2024 exceeded this mark, the official limit is not yet breached. Scientists emphasize that every 0.1C of warming increases risks like intense storms, wildfires, and heatwaves, necessitating urgent global action to maintain the long-term goal.
3Risks of Crossing Thresholds
Warming beyond 2C poses severe threats, including rising sea levels from melting ice sheets and increased food insecurity. Irreversible tipping points, such as the collapse of the Greenland Ice Sheet or the loss of the Amazon rainforest, could accelerate climate change. Once these thresholds are crossed, environmental changes may become permanent and uncontrollable.
4Climate Finance and Support
Richer nations committed to providing $100bn annually by 2020 to assist developing countries with green transitions. While this goal was reached after 2022, developing nations seek more support. In 2023, a dedicated fund for loss and damage was established, with Nepal receiving the first payout following devastating 2026 flash floods.
5Political Shifts and Withdrawals
The United States, the world's second-largest emitter, withdrew from the agreement in January 2026 under President Donald Trump. This follows a previous withdrawal and subsequent rejoining in 2021. Currently, only Iran, Libya, and Yemen remain outside the agreement, highlighting the near-universal international consensus on the necessity of addressing global greenhouse gas emissions.
6Evolution of COP Summits
Annual COP summits track progress on Paris commitments. COP28 in 2023 marked the first agreement to transition away from fossil fuels and treble renewable capacity by 2030. However, COP30 in Brazil failed to explicitly mention fossil fuels, shifting the focus to voluntary roadmaps that will be further discussed at the upcoming COP31.
7Urgency of Emission Cuts
The UN Emissions Gap Report warns that the 1.5C limit will likely be exceeded soon without drastic intervention. To return to 1.5C by 2100, global emissions must drop by 18% between 2025 and 2030. Current government pledges only cover half of these required cuts, risking warming of nearly 3C by century's end.
8Future Outlook and Action
COP31 is scheduled for November 2026 in Antalya, Turkey, co-hosted by Australia. Beyond the formal COP process, a coalition of 57 countries is organizing independent conferences to accelerate the phase-out of fossil fuels. These efforts reflect a growing recognition that current policy trajectories are insufficient to avoid the most severe climate impacts.
Original article: BBC News — Understanding the Paris Agreement and the 1.5C Climate Threshold