Greenhouse gases reach new historic highs, warns UN

Greenhouse gas concentrations reached record highs in 2025, exacerbating global warming, according to a UN report. The average global CO2 level hit 426.8 ppm, a 53% increase since 1750. Methane and nitrous oxide also reached unprecedented levels, driven by human activities. Although CO2 growth slowed in 2025 due to improved carbon absorption by ecosystems, levels are expected to rise again in 2026 due to fossil fuel use and climate change.