Flux continu

For many of us the climate crisis mainly calls to mind rising global temperatures, but the crisis goes far beyond this – we are at risk of pushing our planet across climate ‘tipping points,’ critical thresholds where small changes can lead to abrupt and irreversible shifts in the Earth’s climate system. One major element in climate tipping is a huge system of ocean currents, the Atlantic Meridional Overturning Circulation (AMOC), which is responsible for Europe's relatively mild climate. Past climate patterns show that these currents can switch abruptly between today’s vigorous flow and a much weaker flow state. A future shutdown would have potentially devastating consequences in Europe and around the world.

We're nearly halfway through the 2020s, dubbed the most decisive decade for action on climate change. Where exactly do things stand? Climate impact scholar Johan Rockström offers the most up-to-date scientific assessment of the state of the planet and explains what must be done to preserve Earth's resilience to human pressure.

Under current emission trajectories, temporarily overshooting the Paris global warming limit of 1.5 °C is a distinct possibility. Permanently exceeding this limit would substantially increase the probability of triggering climate tipping elements. Here, we investigate the tipping risks associated with several policy-relevant future emission scenarios, using a stylised Earth system model of four interconnected climate tipping elements. We show that following current policies this century would commit to a 45% tipping risk by 2300 (median, 10–90% range: 23–71%), even if temperatures are brought back to below 1.5 °C. We find that tipping risk by 2300 increases with every additional 0.1 °C of overshoot above 1.5 °C and strongly accelerates for peak warming above 2.0 °C. Achieving and maintaining at least net zero greenhouse gas emissions by 2100 is paramount to minimise tipping risk in the long term. Our results underscore that stringent emission reductions in the current decade are critical for planetary stabili

Small increase in temperature of intruding water could lead to very big increase in loss of ice, scientists say

The Global Tipping Points Report was launched at COP28 on 6 December 2023. The report is an authoritative assessment of the risks and opportunities of both negative and positive tipping points in the Earth system and society. Global Tipping Points is led by Professor Tim Lenton from the University of Exeter’s Global Systems Institute with the support of more than 200 researchers from over 90 organisations in 26 countries.

A recent paper suggested damaging climate tipping points could be closer than first thought.

An international team of scientists has warned against relying on nature providing straightforward 'early warning' indicators of a climate disaster, as new mathematical modeling shows new fascinating aspects of the complexity of the dynamics of climate. It suggests that the climate system could be more unpredictable than previously thought.

Collapse in system of currents that helps regulate global climate would be at such speed that adaptation would be impossible

Scientists now have a better understanding of the risks ahead and a new early warning signal to watch for.

RealClimate: A new paper was published in Science Advances today. Its title says what it is about: "Physics-based early warning signal shows that AMOC is on tipping course." The study follows one by Danish colleagues which made headlines last July, likewise looking for early warning signals for approaching an AMOC tipping point (we discussed it here),