Research on climate change impacts shows that rising greenhouse gas emissions are already transforming natural and human systems and will intensify with further warming.

Globally, average temperatures have increased by more than 1 degree Celsius since preindustrial times, with land areas warming faster than oceans. This drives more frequent and intense heatwaves, heavier rainfall events and longer droughts in many regions. The likelihood of record breaking extremes has increased sharply and is projected to keep rising as warming continues.

Cryosphere changes are pronounced. Glaciers and ice sheets in Greenland, Antarctica and mountain regions are losing mass, contributing to sea level rise. Arctic sea ice extent and thickness have declined, altering ecosystems and amplifying regional warming. Permafrost is thawing, releasing additional greenhouse gases.

Sea level is rising due to thermal expansion of seawater and melting ice. This increases coastal flooding, erosion and saltwater intrusion into freshwater systems, threatening low lying cities, deltas and small islands. Higher sea levels also worsen storm surge impacts.

Ecosystems are shifting as species move poleward and to higher elevations. Many terrestrial and marine species face increased extinction risk, particularly those with limited mobility or specialized habitats such as coral reefs. Ocean warming and acidification reduce oxygen levels and impair marine organisms that build shells or skeletons.

Human systems are affected through reduced crop yields in vulnerable regions, heightened water stress, health impacts from heat and disease, and damage to infrastructure. Economic losses grow with warming, with disproportionate impacts on poorer communities and regions. Adaptation can reduce some risks, but many impacts intensify rapidly beyond 1.5 to 2 degrees Celsius of warming, underscoring the importance of rapid emissions reductions.