Key Climate Indicators

Indicator Value Source
Global mean temperature (2024) 1.55 ± 0.13°C above 1850–1900 WMO
CO₂ concentration 427+ ppm NOAA GML
Warmest year in record 2024 (175-year record) WMO
Sea-level rise rate 5.9 mm/year (2024) WMO
Ocean heat absorbed (2025) 23 zettajoules IAP/CAS

What 1.5°C Means

Crossing the 1.5°C threshold signals a world of more frequent and intense heatwaves, accelerated ice-sheet melt, disrupted weather patterns, and threatened food security for billions. Sea-level rise and ocean warming set in motion today are irreversible for hundreds of years, locking in consequences that will outlast every institution currently governing our response.

Sources

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