Climate Change
Learn about climate change — the long-term warming of the planet caused by human activities, its impacts on ecosystems and societies, and the global response.
Climate change — the long-term alteration of Earth's average temperature and weather patterns, driven primarily by the burning of fossil fuels — is arguably the defining challenge of the 21st century. Since the Industrial Revolution, human activities have increased atmospheric carbon dioxide levels by over 50%, trapping heat and warming the planet by approximately 1.1°C above pre-industrial levels, with accelerating consequences.
The science is well-established. The greenhouse effect — where atmospheric gases trap solar heat — was identified in the 19th century. By the 1980s, scientists had clear evidence that human emissions were warming the planet. The Intergovernmental Panel on Climate Change (IPCC), established in 1988, has produced increasingly urgent assessments. Yet the gap between scientific understanding and political action has remained stubbornly wide, delayed by fossil fuel industry lobbying, geopolitical disputes over responsibility, and the difficulty of making costly changes to prevent future harms.
The impacts are already visible: more frequent extreme weather events, rising sea levels threatening coastal cities, melting glaciers and Arctic ice, ecosystem disruption, and threats to food and water security — with the poorest and most vulnerable populations bearing the greatest burden. The Paris Agreement of 2015 committed nations to limiting warming to 1.5–2°C, but current policies fall far short. Whether humanity can mobilize the political will and technological innovation needed to avert the worst outcomes remains an open and urgent question.