Context:Record-Breaking January 2025:
- January 2025 was 0.09°C warmer than January 2024, making it the hottest January on record.
- It was 1.75°C warmer than pre-industrial times.
- 18 of the last 19 months hit or surpassed the 1.5°C threshold.
Relevance : GS 3(Environment ,Climate Change)
Scientific Debate on Acceleration:
- James Hansen (Former NASA Scientist) claims global warming is accelerating, with the past 15 years warming twice as fast as the previous 40 years.
- University of Michigan’s Overpeck agrees, saying climate change impacts are getting worse.
Skepticism from Other Scientists:
- Gabe Vecchi (Princeton): Not enough data; could be random variation.
- Michael Mann (University of Pennsylvania): Warming is within climate model predictions.
Natural Climate Factors & Their Impact:
- El Niño (2023-24): Caused temperature spikes, but ended in June 2024.
- La Niña (2025 Onset): Expected to cool global temperatures, but January still broke records.
- Sulphur Pollution Reduction: New shipping regulations reduced sulphur aerosols, which previously reflected sunlight and mitigated warming.
Uncertainty About 2025:
- Earlier predictions suggested 2025 would be cooler than 2024 due to La Niña.
- Hansen contradicts this, arguing 2025 may surpass 2024’s record.
Implications:
- Climate Thresholds & Paris Agreement:
- 1.5°C threshold is being exceeded frequently but not permanently yet.
- Scientists won’t declare the Paris Agreement limit breached until global temperatures stay above it for 20 years.
Policy & Global Response:
- Need for urgent emission reductions from fossil fuels.
- Climate policies may need adjustments if acceleration is confirmed.
Scientific Uncertainty & Debate:
- Conflicting views highlight the complexity of climate science.
- More long-term data needed to confirm if warming is truly accelerating.
