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Context

• A study has found that even at the current levels of warming in the world, several climate 'tipping points' could be crossed, setting off irreversible, catastrophic, and self-perpetuating changes.

Findings

• While the world is worried about restricting global warming to within 1.5 degree or 2 degree Celsius, a new study published recently in Science journal, has found that even the current level of average global temperatures — about 1.1 degree Celsius higher than preindustrial times — is enough to trigger catastrophic changes in several climatic systems.
• The study has warned that the thresholds for many of these systems could be crossed at the current levels of warming, setting off self-perpetuating changes that could put living beings at serious risk.
• Its findings could lead to a reassessment of global efforts to fight climate change, and are being widely discussed in scientific circles.

Tipping Point

• In climate science, a tipping point is a critical threshold that, when crossed, leads to large and often irreversible changes in the climate system. If tipping points are crossed, they are likely to have severe impacts on human society.
• Tipping behaviour is found across the climate system, in ecosystems, ice sheets, and the circulation of the ocean and atmosphere.
• The global tipping points identified are: the collapse of the Greenland, west Antarctic and two parts of the east Antarctic ice sheets, the partial and total collapse of Amoc, Amazon dieback, permafrost collapse and winter sea ice loss in the Arctic.

Have we passed any tipping points?

• Until recently, scientists thought that it was unlikely that we would pass any global-scale climate tipping points this century. However, there is now increasing evidence and agreement that we are closer to crossing tipping points than we thought.

Final Thought

• Nearly 200 countries signed the 2015 Paris Agreement, pledging to keep global warming below 2C. However, current national emissions pledges – even if they are met – would lead to 3C of warming.
• Experts argued that further international action was needed, as it could slow the impacts of climate change, giving more time for people to adapt. We might already have crossed the threshold for a cascade of inter-related tipping points. However, the rate at which they progress, and therefore the risk they pose, can be reduced by cutting our emissions.
• The sixth assessment report of the IPCC had said that global emissions of greenhouse gases needed to peak by 2025, and reduce by 43 per cent from current levels by 2030, if the 1.5 degree Celsius target was to be achieved.
• The stability and resilience of our planet is in peril. International action – not just words – must reflect this.

https://indianexpress.com/article/explained/explained-climate/tipping-points-of-global-warming-8216990/

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