When world leaders gathered at the edge of the Amazon on Monday, the first battle of COP30 was not over carbon markets or finance – it was over truth itself. Opening the U.N. climate summit in Belém, Brazilian President Luiz Inácio Lula da Silva issued a blunt challenge to governments: stop letting climate deniers and digital disinformation sabotage the fight against global heating.

“COP30 will be the COP of truth,” Lula told delegates, in remarks reported by the Los Angeles Times in an article on the summit’s opening day “Brazilian president urges nations to defeat climate denial as COP30 begins”. He warned that “obscurantists” are exploiting social media algorithms to spread lies, stir hatred and erode trust in institutions, universities and scientific evidence. His message was clear: unless governments decisively confront the organised campaigns that downplay or deny the climate crisis, they will lose precious time that the planet does not have.

The stakes behind that warning became obvious almost as soon as the speeches stopped. Even agreeing on the agenda for COP30 turned into a political minefield. Small island states, whose very survival depends on limiting sea-level rise, pushed hard for formal discussions on how the world should respond to the latest round of national emission-cutting pledges. Meanwhile, Saudi Arabia, India and several others insisted that the talks also take up so-called unilateral trade measures – widely seen as a reference to the European Union’s new carbon border levy on emissions-intensive imports “Brazilian president urges nations to defeat climate denial as COP30 begins”.

To prevent the summit from getting stuck on day one, the Brazilian presidency brokered a fragile compromise. Contentious items were removed from the formal agenda and sent to a separate consultation process led by COP30 President André Corrêa do Lago. He has promised to report back to ministers later in the week, opening the door for a broad political declaration at the end of the summit that might touch these issues without letting them derail technical negotiations. It was a reminder that procedural fights can still sap precious time from confronting the core problem: global emissions remain far too high, and the gap between promises and physics is widening.

Lula’s appeal comes exactly ten years after the Paris Agreement entered into force, promising to keep global warming “well below” 2°C and pursue efforts to limit it to 1.5°C. Without that deal, the Brazilian leader noted, the planet would likely be heading towards nearly 5°C of warming this century – an utterly catastrophic scenario. Today, thanks to clean-energy growth and climate policies, the trajectory is lower, but still deadly. A new update to the U.N. climate body’s 2025 NDC Synthesis Report shows that if countries implement their latest national climate plans, global greenhouse gas emissions in 2035 would be around 12% below 2019 levels UNFCCC NDC synthesis update.

That is what U.N. Climate Change Executive Secretary Simon Stiell called “bending the emissions curve downward” – a genuine turning point compared with earlier projections where emissions kept rising UNFCCC NDC synthesis update. But it is nowhere near enough. The Intergovernmental Panel on Climate Change and a previous U.N. analysis have made it clear that to keep a 1.5°C future within reach, emissions must fall by roughly 60% by 2035 relative to 2019 New UN climate change report. That leaves a massive shortfall – a mitigation gap of tens of billions of tonnes of greenhouse gases every year.

The latest Emissions Gap Report 2025: Off Target from the U.N. Environment Programme drives the point home. It finds that new national pledges have only shaved a small amount off expected warming, leaving the world on track for around 2.3–2.5°C of temperature rise by 2100 if current commitments are honoured, and potentially closer to 2.8°C if policies falter. A companion UNEP analysis warns that the world is now likely to blow past the 1.5°C threshold within the next decade, with devastating consequences for sea ice, corals, food security and extreme weather The world is likely to exceed a key global warming target soon. Now what?.

At COP30, U.N. Secretary-General António Guterres put it in stark moral terms. Speaking just days before Lula’s speech, he told leaders that failing to keep 1.5°C alive is “a moral failure and deadly negligence,” warning that each additional tenth of a degree raises the risk of crossing irreversible tipping points in the Amazon, ice sheets and oceans Guterres 1.5°C warning. The World Meteorological Organization has already confirmed that the last eleven years are the hottest on record, and that 2023, 2024 and 2025 together form the most scorching three-year period humanity has ever measured UN hottest years warning. Scientists now say a temporary overshoot of 1.5°C is virtually unavoidable – and how quickly we slash emissions will determine how long we stay in the danger zone.

In that context, Lula’s attack on climate denial is not just about rhetoric. Around the world, fossil-fuel interests and political actors are pouring money into campaigns that question basic climate science, exaggerate the costs of clean energy or falsely claim that nothing humans do will change the outcome. Increasingly, these messages are amplified by opaque recommendation algorithms on social media platforms, which push divisive content because it keeps people online longer. By warning that “they control algorithms, sow hatred and spread fear,” Lula was calling out this system – one that turns lies into viral weapons just as the world needs a clear understanding of risk and responsibility “Brazilian president urges nations to defeat climate denial as COP30 begins”.

Brazil is also trying to use COP30 to showcase solutions. The government has announced a “Tropical Forest Forever” facility that aims to mobilize around $125 billion to protect rainforest countries and secure land rights for Indigenous and traditional communities, who are among the most effective guardians of carbon-rich forests Tropical Forest Forever facility. If fully funded and well governed, such initiatives could slow deforestation in the Amazon and other tropical regions, cutting emissions while safeguarding biodiversity and local livelihoods.

Yet even bolder action will be needed to close the yawning gap between current plans and what science demands. Independent analysis of the new UNEP report estimates that on present trends, global emissions in 2030 could still reach about 53 billion tonnes of CO₂-equivalent, and 48 billion tonnes by 2035 – far above the roughly 36 and 25 billion tonnes compatible with a 1.5°C pathway 2025 emissions gap summary. Every year of delay makes the eventual transition more disruptive, more expensive and more likely to trigger social and political backlash Overshoot and net zero analysis.

For communities already on the front lines, the danger is not abstract. Small island states face land loss and saltwater intrusion. Farmers in drought-prone regions are watching harvests fail. City dwellers are enduring ever more lethal heatwaves and floods. Many of these communities have contributed almost nothing to the emissions heating the planet, yet they are being forced to adapt with limited resources and meagre support.

Against this backdrop, the question raised at the start of COP30 is brutally simple: will governments move beyond speeches to deliver the deep, rapid cuts in fossil fuels that science and justice demand? Lula has framed this summit as a test of whether truth can triumph over denial, and whether the world is willing to confront the interests that profit from delay. The numbers from the U.N. could not be clearer: a 12% fall in emissions by 2035 is not a victory, it is a warning siren. Unless countries leave Belém with a plan to turbocharge climate action – phasing out coal, oil and gas, protecting forests and massively scaling up finance – the “COP of truth” may be remembered instead as the moment the world looked the climate emergency in the eye, and still chose half-measures.

The window to avoid irreversible damage is closing fast. Every fraction of a degree of avoided warming will save lives and livelihoods. Defeating climate denial, in all its forms, is now part of the emergency response.