Key Highlights of the Report

Current Climate Status

  • Global warming: Approximately 1.4°C above pre-industrial levels, increasing at ~0.25°C per decade
  • Carbon budget: Only ~130 billion tons of CO₂ remaining (from 2026) for 50% chance of staying within 1.5°C
  • Emission rate: ~40 billion tons CO₂ per year means budget exhaustion in ~3 years
  • Probability: 75% chance of five-year mean temperature exceeding 1.5°C during 2026-2030

Cost of Delayed Action

  • Every 5 years of high emissions adds ~0.1°C to peak warming
  • Emissions since 2015 have already increased minimum achievable peak warming by 0.2°C
  • Current policy trajectory leads to 2.6°C warming by 2100 (range: 1.9°C-3.6°C)
  • Even full NDC implementation still results in 1.8°C peak warming

The 'Overshoot, Peak, and Decline' Framework

This framework represents a strategic shift from prevention to management:

  1. Exceedance (Overshoot): Period when warming exceeds 1.5°C but hasn't peaked
  2. Plateau/Peak: Maximum warming level before decline begins
  3. Decline: Sustained net-negative emissions cause temperatures to fall
  4. Stabilization: Return to or below 1.5°C target

Critical Role of Methane Mitigation

  • Methane contributes ~0.5°C to global warming
  • Short atmospheric lifetime enables faster cooling effect than CO₂ reductions
  • 60-70 million tonnes reduction in hard-to-abate methane ≈ removing 220 Gt CO₂
  • Global Methane Pledge (COP26): 30% reduction from 2020 levels by 2030
  • Countries NOT joined: India, China, Russia, Iran

Geopolitical Challenges

  • US withdrawal from Paris Agreement, UNFCCC, IPCC, and Green Climate Fund
  • West Asia conflict (2026): Largest oil supply disruption, cutting 14+ million barrels/day
  • Risk of governments reverting to coal and fossil fuels

Consequences of 1.5°C Overshoot

Cryosphere & Sea Level

  • Glaciers (outside Greenland/Antarctica): 25-40% mass loss by 2100
  • Sea-level contribution: 9-15.4 cm from glacier melt
  • Every 100 years above 1.5°C commits ~40 cm additional rise by 2300
  • Sea-level rise persists for centuries due to deep-ocean warming

Ecosystem Tipping Points

  • AMOC weakening/collapse risk with centuries-long recovery
  • Amazon rainforest: potential shift from carbon sink to net source
  • West Antarctic Ice Sheet: irreversible retreat even at lower warming levels

Food & Ocean Security

  • Global food production: up to 14% decline by 2050
  • Ocean acidification and deoxygenation persist for centuries

Key Recommendations

Climate Finance

  • Scale up Fund for Responding to Loss and Damage (FRLD) before peak warming
  • Gap: $800 million pledged vs $395 billion annual need
  • $1 invested in resilient infrastructure = $4 in avoided losses
  • Use Multidimensional Vulnerability Index (MVI) for allocation

Mitigation Actions

  • Immediate deep CO₂ and methane reductions
  • Shift from Net-Zero to legally binding Net-Negative targets
  • Developed nations: net-negative first under CBDR-RC principle
  • Renewables: 60-70% of electricity by 2030

Carbon Dioxide Removal (CDR)

  • CDR supplements, NOT replaces, emission reductions
  • Requires strong governance for environmental and land-use risks
  • Both conventional (afforestation) and novel (Direct Air Capture) methods needed

Protecting Vulnerable Nations

  • Formalize legal mechanisms for SIDS sovereignty and maritime EEZs under UNCLOS
  • Integrate employment protection and social security in just transition
  • Treat protected areas as climate infrastructure

Related Constitutional & International Provisions

  • Paris Agreement (2015): 1.5°C limit commitment
  • UNFCCC: Framework convention on climate change
  • CBDR-RC: Common But Differentiated Responsibilities and Respective Capabilities
  • UNCLOS: Maritime entitlements and EEZ protection
  • Global Methane Pledge: COP26 initiative (2021)

UPSC Significance

This report is crucial for understanding:

  • Evolution of climate diplomacy beyond the 1.5°C target
  • Need for transformational adaptation vs incremental measures
  • Climate justice and Loss and Damage finance mechanisms
  • India's position on Global Methane Pledge