Are climate tipping points like ‘turning off the Gulf Stream’ and release of methane from the Arctic a cause for concern?
As carbon dioxide levels rise, the risk of severe and potentially irreversible climate change increases. In the past, the climate system has shifted abruptly when thresholds were crossed. Such “tipping points” become more likely as warming exceeds 1.5°C and continues to intensify, though their timing and likelihood remain uncertain.
One widely discussed example is a slowdown of the Atlantic Meridional Overturning Circulation (AMOC), which includes the Gulf Stream and helps transport heat to the North Atlantic. While most models do not project an abrupt collapse in the near term, past disruptions during the last ice age show that such changes can have widespread climate impacts. Other concerns include the release of methane and carbon dioxide from thawing permafrost, and the prospect that major ice sheets could pass thresholds where faster thinning and retreat of ice margins would lead to higher sea-level rise.
Major ecosystems may also face tipping risks. Increased drought and deforestation threaten the Amazon rainforest’s ability to recycle moisture, potentially triggering difficult-to-reverse decline. Boreal forests have historically retreated south-to-north during warm periods, affecting carbon storage and ecosystem stability.
Even gradual warming can produce abrupt impacts in natural and human systems. Coral bleaching linked to marine heatwaves could lead to the demise of coral ecosystems in some regions. Infrastructure designed for past climate conditions may fail as sea levels rise or permafrost thaws. Species unable to adapt or relocate may decline rapidly, while others—such as bark beetles in warming regions—can expand suddenly, reshaping ecosystems.
Although the most extreme tipping events are considered unlikely this century, uncertainty is high, and risks increase with every increment of warming.
Page last updated: July 2026
Find out about the Royal Society's latest work on climate change and biodiversity