1363. Climate Tipping Points

Since the Industrial Revolution, greenhouse gas emissions have trapped heat around the Earth, causing global temperatures to rise by approximately 1.4°C. Unless urgent action is taken, we are likely to soon surpass the 1.5°C global warming limit set by countries in 2015.

The Global Tipping Points Report 2025, released ahead of next month's United Nations Climate Change Conference (COP30) in Brazil, points out that multiple Earth systems are rapidly approaching tipping points, and if climate change continues unabated, glaciers will melt, rainforests will disappear, and ocean currents will collapse, with devastating impacts on people and nature.

What impact will climate tipping points have? Even a warming of just 1°C will likely trigger climate tipping points of all kinds, with billions of people around the world facing impacts such as more extreme weather, worsening food security, and rising sea levels. One such tipping point is already underway, with coral reefs already in the midst of the worst global bleaching event on record, with approximately 85% of reefs affected since it began in 2023. The report estimates that corals, which support up to 40% of marine life, will exceed this tipping point if global temperatures exceed 1.2°C and will experience further declines over the next century.

Other tipping points, such as the large-scale loss of glaciers around the world and the resulting rise in sea levels, are almost certain to occur unless urgent action is taken to achieve net-zero emissions. Further tipping points, such as the melting of the Antarctic ice sheet and the collapse of the Subpolar Circumpolar Current, are likely to occur if global warming exceeds 1.5°C. Triggering one tipping point can lead to the collapse of others, like dominoes falling one after the other. For example, melting permafrost will release greenhouse gases trapped for thousands of years, further accelerating global warming. This will increase the likelihood of other tipping points, such as melting Arctic ice.

The most severe tipping point mentioned in the report is the Atlantic Meridional Overturning Circumference (AMOC). This current regulates temperatures in Europe and North America and stabilizes nearly half of the other known tipping points. If climate change causes the AMOC to collapse, the continents will face more extreme climate changes than our society has ever experienced. However, the exact timing of this tipping point remains unclear. Some estimates suggest that AMOC collapse is already underway, while others predict it will cease at a much higher temperature. Given the associated risks, further research and policy changes are needed.

The good news is that it's possible to prevent this from happening. The report identifies "positive" tipping points for the growth of net-zero industries. For example, solar photovoltaic capacity currently doubles every two to three years, and high adoption rates are driving down costs. As solar panels become more widespread, investment in battery technology has increased, with battery storage prices falling 84% over the past decade and capacity increasing. As solar power becomes more affordable, it is bringing electricity to more people around the world, revitalizing economies and enabling life-saving equipment to be powered even in the most remote areas.

The report also calls for further investment in other sustainable industries, from domestic heat pumps to eco-friendly agriculture, to help them reach their respective tipping points. We are not far from achieving self-sustaining economic growth, where rising demand drives innovation and lowers prices for all.

Next Monday, October 27th, the JIRCAS International Symposium will discuss international collaboration to improve the sustainability of the Earth system and promote environmentally friendly agricultural technologies.

JIRCAS International Symposium 2025
Accelerating Application of Agricultural Technologies in the Asia-Monsoon Region: Taking Stock and the Way Forward for Enhancing Production Potentials and Sustainable Food Systems
Date: 2025-10-27(Mon) 13:30～17:30 (13:00 Admission) (JST)
Place: "Hitotsubashi Hall" and On-line 
Event Site: https://www.jircas.go.jp/en/symposium/2025/e20251027_jircas

(Reference)
Lenton, T. M., (eds), 2025, The Global Tipping Points Report 2025. University of Exeter, Exeter, UK. ©The Global Tipping Points Report 2025, University of Exeter, UK. https://global-tipping-points.org/

Contributor: IIYAMA Miyuki, Information Program