GENEVA - The Earth's climate is more out of balance than at any time in observed history, as greenhouse gas concentrations drive continued warming of the atmosphere and ocean as well as melting of ice, the World Meteorological Organization (WMO) said on Monday.

March 23 is World Meteorological Day, with the theme "Observing Today, Protecting Tomorrow." On the same day, the WMO released the State of the Global Climate report 2025, analyzing a range of key climate indicators, including greenhouse gas concentrations, surface temperature, ocean heat and acidification, sea level rise, Antarctic sea ice extent, and glacier melt.

The report confirmed that 2015-2025 were the hottest 11 years on record, and 2025 was the second or third hottest year on record, at about 1.43 degrees Celcius above the 1850-1900 average. Extreme events around the world, including intense heat, heavy rainfall and tropical cyclones, caused disruption and devastation, highlighting the vulnerability of interconnected economies and societies.

The ocean continues to warm and absorb carbon dioxide. Over the past two decades, the ocean has absorbed the equivalent of about 18 times the annual human energy use each year. In 2025, ocean heat content (to a depth of 2,000 meters) reached the highest level since records began in 1960, surpassing the previous high set in 2024.

Data from individual monitoring stations showed that levels of three main greenhouse gases -- carbon dioxide, methane and nitrous oxide -- continued to increase in 2025.

For the first time, the report included Earth's energy imbalance as a key climate indicator. The Earth's energy balance measures the rate at which energy enters and leaves the Earth system.

Earth's energy imbalance has been increasing since its observational record began in 1960, particularly in the past 20 years. It reached a new high in 2025.