Editor's note: Decision Makers is a global platform for decision makers to share their insights on events shaping today's world. Inger Andersen is the executive director of the UN Environment Programme. The article reflects the author's opinions and not necessarily those of CGTN.

In 2015, nearly every country in the world came together in Paris to agree to pursue efforts to limit global warming to 1.5 degrees Celsius. 

It reflected a widespread understanding of the growing risks of climate change: extreme weather events, crop failures, desertification, biodiversity loss and other devastating impacts on people and nature.

Notwithstanding that breakthrough in international cooperation, and the progress made in adopting cleaner technologies and practices, today the chance of holding warming to 1.5 degrees Celsius without overshoot is gone.

Recent UN Environment Programme (UNEP) science shows how narrow the path back to 1.5 degrees Celsius has become. Our latest reports show the lowest possible overshoot scenario means global temperatures must peak at around 1.7-1.8 degrees Celsius near mid-century, with roughly a 50% chance of returning to 1.5 degrees Celsius or below by 2100.

This requires rapid, significant and, frankly, unprecedented global greenhouse gas emission cuts. Delaying emissions cuts only forces us to rely on carbon removal technologies to lower global temperatures, a strategy that remains complex, costly and unproven at the scale required. It is possible, but only if we act boldly now. 

The economics of this new reality are stark. Some countries have invested substantial political and financial capital in climate action, including mitigation efforts to make these emission reductions, as well as investments in managing the impacts of climate change. In doing so, they have become leaders in producing and exporting new technologies, from solar panels and electric vehicles to batteries. Others have invested in early warning systems, sustainable cooling or food waste reduction, protecting lives and saving money.

For example, not acting is a massive economic failure. For every $1 we invest in cleaner air and a stable climate, we get $15 back in economic and social returns. 

Yet too many have done too little to prevent the worst impacts of climate change. The years 2015 through to 2025 were the warmest years on record. This year has already brought deadly heatwaves, widespread droughts, floods and wildfires, while glaciers continue to collapse and retreat. No region or country is immune.

And as temperatures rise, so does the bill for adapting to climate impacts.

The UNEP's latest Adaptation Gap Report 2026: Ready? Not, finds that – yet again – adaptation finance flows fall drastically short of what is needed.

Developing countries need around $305 billion a year by 2035 to cope with growing climate impacts. International public adaptation finance reached only $28-32 billion in 2024. Even if the call by world governments to at least triple adaptation finance by 2035 is met, it would cover no more than 30% of needs.

When resilience is underfunded, losses and damage mount. Some losses – including the tragic loss of human lives and irreplaceable ecosystems – cannot be repaired at any price. The Fund for responding to Loss and Damage received requests totaling $2.8 billion in its first round, against an initial funding envelope of just $342 million.

Investing in flood defenses, early warning, water security and heat-resilient buildings can prevent far greater costs in the form of losses and damage. Investing in rapid and large-scale emissions reductions can also reduce the costs of adaptation.

Governments around the world face difficult budget choices, competing priorities and no shortage of emergencies. Yet when it comes to climate action, there is no cost-free choice. The choice is simple: Invest in a safer, more prosperous future now, or pay a much larger, much more volatile bill later.

As countries gather in Antalya, Türkiye, for the 31st UN Climate Change Conference, they have an opportunity to make that investment. Accelerating clean energy and electrification, improving energy efficiency and sustainable cooling, reducing methane emissions and food waste, and scaling up finance for adaptation and loss and damage are all steps toward achieving our collective global goals and a safer future.

Our choices today will determine whether we can bring temperatures back down at all.

I understand the skepticism surrounding our ability to bring global temperatures back down to 1.5 degrees Celsius. Even a return will bring us back to a different world, yet it will be a safer world. But I remain determined. Climate action is not a burden – it is action that creates jobs, secures energy, food and water security, ensures cleaner air for children to play outside and safeguards the nature we cannot afford to lose.

If nothing else, we must all remember that every additional fraction of a degree and every additional year of warming above 1.5 degrees Celsius increases climate impacts and risks.

We have lost the shortest road to 1.5 degrees Celsius. We cannot afford to lose the way back. Either we pay now, or future generations pay far more later.

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