A really simple guide to climate change and global warming impacts

Global temperatures are rising due to human activities, creating serious risks for communities and ecosystems across the globe. Climate change represents the long-term shift in average weather conditions and temperatures on Earth. The planet has experienced rapid warming for about a century, altering weather patterns significantly. According to the Met Office, every decade since the 1980s has been warmer than the preceding one, with 2024 registering as the hottest year on record largely due to climate change. This period was also the first calendar year to exceed 1.5C of warming compared to pre-industrial levels from the late 1800s, based on findings from the Copernicus climate service. High temperatures persisted through 2025 despite temporary cooling from the La Niña weather pattern, and the combination of climate change with El Niño suggests 2026 will likely rank among the warmest years ever documented.

While the Earth's climate has historically varied through natural cycles, the UN Intergovernmental Panel on Climate Change (IPCC) notes that natural factors cannot account for the rapid warming observed over the past century. This accelerated heating is driven by human activities, particularly the burning of fossil fuels such as coal, oil, and gas across domestic, industrial, and transport sectors. Burning these materials releases greenhouse gases, predominantly carbon dioxide, which functions like an insulating blanket that traps thermal energy in the lower atmosphere. Since the onset of the Industrial Revolution, atmospheric carbon dioxide levels have climbed by more than over 50 percent, displaying a distinct chemical fingerprint that matches emissions from fossil fuel combustion.

Rapid warming driven by human fossil fuel use threatens people and ecosystems globally.

The consequences of this atmospheric heating include frequent intense heatwaves, heavy rainfall, accelerated melting of glaciers and ice sheets that contribute to rising sea levels, and warmer oceans that strengthen storms and damage marine life. These alterations are already impacting populations and economies. In August 2026, flash floods in Nepal resulted in over 1,400 fatalities, with Finance Minister Swarnim Wagle noting that rebuilding could consume up to a tenth of the national economy. Scientists from the World Weather Attribution group concluded that climate change elevated the probability of the glacier collapse responsible for the flooding. Under the 2015 Paris agreement, nearly two hundred countries pledged to pursue efforts to restrict global warming to 1.5C above pre-industrial levels over a twenty-year average, as long-term warming at this threshold brings profound impacts for numerous populations.

Why it matters

Human activities are driving rapid planetary warming that poses serious threats to populations and economic stability worldwide. Understanding how greenhouse gas emissions alter global weather patterns helps explain the increasing frequency of extreme events like severe floods and heatwaves, which carry devastating human and financial costs for affected nations.