The Message From The IPCC Report

Context: Equitable cumulative emission targets and not net-zero is the key to achieving the Paris Agreement’s temperature goals.

Takeaways from the Sixth Assessment Report (AR6) of the Intergovernmental Panel on Climate Change (IPCC) titled, ‘Climate Change 2021: The Physical Science Basis’

• Rise in global surface temperature: Which is now higher by 1.07oC since the pre-industrial era: 
  • Set to cross the 1.5oC limit within 10-15 years.
• Major pollutants and their impacts:
  • Carbon dioxide is the dominant source of warming.
  • Role of aerosols: Aerosols contribute to reducing the impact of warming by other greenhouse gases by almost a third.
  • Methane reduction is particularly significant only as part of the endgame.
• Recalibration of climate predictions: The value of equilibrium climate sensitivity, that is, the measure of how a specified increase in carbon dioxide concentration translates into long-term surface temperature rise, is now pinned down to the range of 2.5oC-4.0oC, with the best estimate of 3oC, compared to the 5th Assessment Report range of 1.5oC- 4.5oC.
• An increase in climate extremes: With heatwaves, extreme rainfall events and the occurrence of extreme sea levels are all expected to intensify and be more frequent.
• Air pollution reduction and steep climate change mitigation are not complementary goals: These require independent efforts over the short and medium-term.
• Cumulative emission reduction rather than reaching net-zero: New Zero is not the determining factor to limit temperature rise to 1.5oC or 2oC; the determining factor is the cumulative emissions.
  • The remaining carbon budget for 1.5oC is at a mere 500 billion tonnes of carbon dioxide: This cannot be met by promises of net-zero 30 years from now.
  • Historical cumulative emissions are the cause of the climate crisis that the world faces today. Thus, the report is a “clarion call for developed countries to undertake immediate, deep emission cuts”.

Conclusion: Focusing on definite cumulative emission targets keeping equity and historical responsibility in view, immediate emission reductions by the developed countries, investment in new technologies and their deployment, and a serious push to the mobilisation of adequate climate finance is the need of the hour.