Report confirms record-high greenhouse gases, global sea level and ocean heat in 2025

According to the 36th annual State of the Climate report, greenhouse gas concentrations, global sea level and ocean heat content all reached record highs in 2025.

The top 3

  1. Top Three Most Potent Greenhouse Gases: Carbon dioxide, methane, and nitrous oxide are identified as the top three most harmful greenhouse gases due to their ability to absorb and radiate heat, and their persistence in the environment.
  2. Nations with Highest Cumulative CO2 Emissions: The United States has contributed the most to cumulative CO2 emissions since 1750, followed by China and Russia, accounting for significant shares of historical emissions.
  3. Highest Atmospheric CO2 Levels in 800,000 Years: Atmospheric CO2 concentrations in 2025 have reached levels not seen in at least 800,000 years, significantly surpassing the natural fluctuation range observed over this period.

Sources

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