Washington, Feb 5 : A new research by scientists at the University of East Anglia in England, has listed nine key components of the Earth's climate system which could pass their 'tipping point' this century.
The term 'tipping point' is used to describe a critical threshold at which a small change in human activity can have large, long-term consequences for the Earth's climate system.
For the new research, the authors have coined a new term, 'tipping elements', to describe those components of the climate system that are at risk of passing a tipping point.
In this new research, Professor Tim Lenton of the University of East Anglia (UEA) and colleagues at the Postdam Institute of Climate Impact Research (PIK), Carnegie Mellon University, Newcastle University and Oxford University have drawn up a shortlist of nine tipping elements relevant to current policy-making and calculated where their tipping points could lie.
The nine tipping elements and the time it will take them to undergo a major transition are:
Melting of Arctic sea-ice (approx 10 years), decay of the Greenland ice sheet (more than 300 years), collapse of the West Antarctic ice sheet (more than 300 years), collapse of the Atlantic thermohaline circulation (approx 100 years), increase in the El Nino Southern Oscillation (approx 100 years), collapse of the Indian summer monsoon (approx 1 year), greening of the Sahara/Sahel and disruption of the West African monsoon (approx 10 years), dieback of the Amazon rainforest (approx 50 years), and, dieback of the Boreal Forest (approx 50 years).
According to Professor Lenton, "Our findings suggest that a variety of tipping elements could reach their critical point within this century under human-induced climate change. The greatest threats are tipping of the Arctic sea-ice and the Greenland ice sheet, and at least five other elements could surprise us by exhibiting a nearby tipping point."
The research also demonstrates how, in principle, early warning systems could be established using real-time monitoring and modelling to detect the proximity of certain tipping points.