Breaching 1.5°C Threshold

Why in News?

• The year 2024 has become the first calendar year to breach the 1.5°C global warming threshold, a significant milestone in the ongoing battle against climate change.
• This breach, calculated relative to pre-industrial temperature levels (1850-1900 averages), is based on datasets from the Copernicus Climate Change Service and the World Meteorological Organization (WMO).

Introduction

• The breach of the 1.5°C global warming threshold marks a critical turning point in understanding the planet’s warming trend and its implications.
• While the 1.5°C mark is an arbitrary threshold established by the 2015 Paris Agreement, it serves as a warning for severe climate impacts.
• This development highlights the urgent need for global efforts to curb greenhouse gas emissions and mitigate climate risks.

Key Highlights of Breaching 1.5°C

Significance of the 1.5°C Threshold

• 1.5°C in Paris Agreement:

  • The 2015 Paris Agreement identified 1.5°C as a critical benchmark to prevent catastrophic climate impacts.
  • Breaching this level signals worsening impacts but does not imply an immediate violation of the Paris Agreement’s goals.

• 2024 Breach:

  • For the first time, global average temperatures in 2024 reached 1.6°C above pre-industrial levels.
  • This breach is significant but focuses on long-term trends, not isolated years.

Data Confirming the Breach

• Copernicus Climate Change Service:

  • Reported a 1.6°C rise in global temperatures above pre-industrial levels for 2024.

• World Meteorological Organization (WMO):

  • Using six datasets, the WMO reported 1.55°C warming for 2024.

• Historical Context:

  • 2024 surpassed 2023 as the warmest year on record.
  • 2016, influenced by a strong El Niño, recorded a warming of 1.29°C above pre-industrial levels.

Factors Behind 2024’s Record Warmth

• El Niño Conditions:

  • Mild El Niño during 2023-2024 contributed to the temperature spike.

• Volcanic Activity:

  • The 2022 Tonga volcanic eruption altered atmospheric composition, impacting global temperatures.

• Reduced Sulphur Emissions:

  • Lower sulphur dioxide emissions from the shipping industry reduced solar radiation reflection, increasing warming.

• Solar Maximum Phase:

  • The Sun’s solar maximum phase in 2024 contributed additional solar energy to Earth.

2024 vs. Previous Years

• 2023: Recorded 1.45°C above pre-industrial levels.
• 2024: Marked a new record with 1.6°C, the highest in history.

• Monthly Trends:

  • Every month since July 2023 (except July 2024) exceeded 1.5°C warming compared to pre-industrial levels.

Implications of Breaching 1.5°C

• Global Emissions:

  • Emissions continue to rise, and 2030 emission cut targets are unlikely to be achieved.
  • Frequent breaches of 1.5°C may become the norm.

• Projections:

  • WMO forecasts annual temperatures could reach 1.9°C above pre-industrial levels by 2028.
  • There is a 50% chance that the five-year average could exceed the 1.5°C mark by 2028.

Key Definitions and Related Facts

• Pre-Industrial Levels (1850-1900 Averages):

  • Reference point for temperature comparisons to gauge the impact of industrial-era emissions.

• El Niño:

  • A climate pattern characterized by warming of the central and eastern tropical Pacific Ocean, influencing global temperatures and weather patterns.

• Sulphur Dioxide Emissions:

  • Reflect solar radiation, creating a cooling effect. Reduced emissions increase warming.

• Solar Maximum:

  • A phase of the solar cycle where the Sun emits maximum energy, increasing Earth’s temperatures.

Future Outlook

2025 and Beyond

• 2025 Forecast:

  • Likely to be cooler than 2024, with temperatures ranging between 1.1°C to 1.4°C above pre-industrial levels.
  • Predicted to be the third warmest year on record after 2024 and 2023.

Long-Term Trends

• Global Warming Rate:

  • Currently exceeding 0.2°C per decade, making breaches of 1.5°C increasingly probable within the 2030s.

World Health Organization (WHO) and Climate Change

What is WHO?

• Established: April 7, 1948.
• Headquarters: Geneva, Switzerland.
• Role:
  • A specialized UN agency responsible for global public health.
  • Coordinates international health responses and develops global health standards.

WHO on Climate Change

• Recognizes climate change as a significant health challenge of the 21st century.
• Focus Areas:
  • Reducing climate-sensitive diseases like malaria and dengue.
  • Strengthening health systems to adapt to climate impacts.
  • Advocating for policies to mitigate climate change and protect public health.

WHO Initiatives

• COP26 Health Programme:

  • Encourages countries to develop climate-resilient and sustainable health systems.

• Health and Climate Change Global Survey:

  • Monitors progress in addressing health risks from climate change.

Conclusion

• Breaching the 1.5°C global warming threshold in 2024 underscores the urgency of global climate action.
• While this milestone does not mark a failure of the Paris Agreement, it emphasizes the need for accelerated emission reductions.
• For students and policymakers, understanding the causes, impacts, and mitigation strategies is crucial to addressing climate change challenges.