Earth's Energy Imbalance Hits Record High, Pushing Planet Beyond Limits
The World Meteorological Organization has issued a stark warning that Earth is grappling with a record energy imbalance, a condition that is warming oceans to unprecedented levels, intensifying extreme weather events, and jeopardising global health and food supplies. The latest annual State of the Global Climate report reveals that the planet's energy has moved dangerously out of balance due to human activities, with oceans absorbing the vast majority of trapped heat.
Unprecedented Heat Accumulation in Oceans
The report confirms that the years 2015 to 2025 represent the hottest 11-year period ever recorded, but the more alarming finding is that surface temperatures experienced by humans account for only 1% of the rapidly accumulating heat within the broader Earth system. Over 90% of this excess energy is absorbed by the oceans, which reached their highest heat content in history last year. The rate of ocean warming has more than doubled over the past two decades compared to the average of the previous 45 years.
This disruption stems from the burning of fossil fuels like oil, gas, and coal, as well as deforestation, which release heat-trapping greenhouse gases such as carbon dioxide, methane, and nitrous oxide. These gases are now at their highest levels in at least 800,000 years, severely disrupting the planet's energy equilibrium. In a stable system, the amount of radiation entering and leaving Earth is roughly balanced, but a heat surplus has been accumulating since at least 1960, with a noticeable acceleration in recent years.
Tracking the Energy Imbalance
For the first time, the report tracks Earth's energy imbalance, showing an increase of approximately 11 zettajoules per year between 2005 and 2025. This is equivalent to about 18 times total human energy consumption. Last year, the imbalance was more than double that average. Currently, humans and other surface life forms directly experience only a small fraction of this energy backup, with 91% absorbed by oceans, 5% by land, 1% warming the atmosphere, and 3% melting polar and mountain ice.
Despite this minimal surface exposure, global temperatures are climbing to alarming levels. Last year ranked as the second- or third-hottest on record, depending on the dataset. World leaders acknowledge that it is now inevitable the planet will temporarily breach the Paris agreement target of limiting heating to 1.5°C above pre-industrial levels. The dire consequences are already evident in faltering harvests, worsening dengue outbreaks, and increasingly severe heatwaves, forest fires, and storms.
Call to Action and Ocean Impacts
UN Secretary-General António Guterres emphasised the urgency, stating, "The state of the global climate is in a state of emergency. Planet Earth is being pushed beyond its limits. Every key climate indicator is flashing red. Humanity has just endured the 11 hottest years on record. When history repeats itself 11 times, it is no longer a coincidence. It is a call to act."
The effects on oceans are profound and long-lasting, though not fully understood. Sea levels are rising at an accelerating pace, and sea ice is at its third-lowest level ever. More heat is moving into ocean depths, affecting circulation patterns and locking in consequences for thousands of years. Nearer the surface, heatwaves and acidification pose growing threats to corals and other marine life, while melting ice reduces the planet's ability to reflect solar radiation, exacerbating the energy imbalance.
No Respite in Sight
There is no immediate relief forecasted. The Pacific is concluding a La Niña phase, typically associated with cooler surface temperatures globally. By the end of this year, forecasts suggest a transition to El Niño, which is expected to bring additional heating. Dr John Kennedy, lead author of the WMO report, warned, "If we transition to El Niño we will see an increase in global temperature again and potentially to record levels." This ongoing trend underscores the critical need for immediate and sustained climate action to mitigate further damage.
