Climate change
Videos
Present-day climate change includes both global warming—the ongoing increase in global average temperature—and its wider effects on Earth's climate system. Climate change in a broader sense also inclu
Sea ice reflects 50% to 70% of incoming sunlight, while the ocean, being darker, reflects only 6%. As an area of sea ice melts and exposes more ocean, more heat is absorbed by the ocean, raising temperatures that melt still more ice. This is a positive feedback process.
Different levels of global warming may cause different parts of Earth's climate system to reach tipping points that cause transitions to different states.
Ecological collapse. Coral bleaching from thermal stress has damaged the Great Barrier Reef and threatens coral reefs worldwide.
Extreme weather. Drought and high temperatures worsened the 2020 bushfires in Australia.
There are many effects of climate change on oceans. One of the most important is an increase in ocean temperatures. More frequent marine heatwaves are linked to this. The rising temperature contribute
Waves on an ocean coast
Global sea ice extent, which combines the sea ice extents in both polar regions, reached a new all-time minimum in February 2025.
Month-by-month chart shows how minimum ice volume usually occurs in September, and maxima usually occurring in April.
Bleached Staghorn coral in the Great Barrier Reef.