The Digester
Week 7, Thursday

Scientists say world is closer to a 'hothouse Earth' point of no return

A new assessment in One Earth warns cascading climate tipping points could push the planet into irreversible runaway warming, with some ice sheets and ecosystems already showing signs of destabilization.

  • The study in One Earth says multiple tipping points could cascade and lock the climate into a hothouse trajectory.
  • Global warming is about 1.3C above preindustrial levels and atmospheric carbon dioxide is likely at its highest in at least 2 million years.
  • Researchers report signs of destabilization in Greenland and West Antarctic ice sheets and warn permafrost, mountain glaciers, the Amazon and polar sea ice are near thresholds.
  • The Atlantic meridional overturning circulation is weakening, which could increase the risk of Amazon dieback and amplify warming.
  • Authors say reversing course may be impossible after crossing certain thresholds, making rapid emissions cuts and precaution vital.
  • The assessment concludes current national climate commitments are insufficient to prevent these risks.