In a powerful address at the World Meteorological Organisation (WMO) in Geneva, United Nations Secretary-General Antonio Guterres emphasized the urgent need to combat climate disinformation and defend scientific integrity. His remarks come ahead of the pivotal COP30 summit in Brazil and follow controversial statements by former US President Donald Trump, who dismissed climate change as a ‘hoax’ and criticized renewable energy technologies. Guterres underscored the critical role of ‘clear-eyed’ climate science in understanding the existential threat posed by global warming, urging nations to reject misinformation, online harassment, and greenwashing. He highlighted the surge in renewable energy investments, noting that nearly all new power capacity in 2024 came from renewables, which he described as the ‘cheapest, fastest, and smartest’ solution to climate change. Guterres also stressed the importance of early warning systems for extreme weather events, particularly for vulnerable nations, as the planet faces unprecedented environmental challenges. With COP30 set to take place in Belem, Brazil, from November 10-21, Guterres called for bold national climate action plans aligned with the goal of limiting global temperature rise to 1.5 degrees Celsius.