The Earth's 'energy imbalance' is at a new high: How our planet has become a heat trap and why it's getting worse

Every year, I read the World Meteorological Organization’s State of the Global Climate report with rising anxiety. When the annual report is released every March, it gives a consolidated scientific roundup on how the previous year has been in relation to the climate crisis.

And so it was on 23 March—World Meteorological Day by the way—when the 2025 report dropped. There was hardly any fanfare. Climate scientists and journalists tweeted about it, there were some statements from UN officials, and that was it. The findings of the report were soon buried under updates of the US and Israel’s war on Iran—ironically enough, a fossil fuel war.

The thing is, the State of the Global Climate should be single biggest bit of news right now, because it paints a dire picture of how human beings are blithely hurtling towards an increasingly uninhabitable planet.

No. That is not alarmist hyperbole.

Here are some of the report’s findings. The eleven hottest years ever recorded have been between 2015 and 2025, with 2024 being the hottest year, and 2025 either the second or third hottest year. The average global temperature last year was 1.43 degrees Celsius above the preindustrial average (1850-1900). The planet is edging dangerously towards breaching the “safe” warming threshold of 1.5 degrees of warming.

A new metric that has been added to the report this year, and that is the measure of the Earth’s ‘energy imbalance’. This refers to the rate at which the planet radiates heat into space as compared to the rate of heating it absorbs due to solar radiation. Under normal circumstances, outgoing energy from the Earth is about the same as the incoming energy from the sun. However this equation has been severely disbalanced due to the increased concentration of heat-trapping greenhouse gases (GHG) in the atmosphere, like carbon dioxide, methane and nitrous oxide. The WMO says that GHG levels have soared “to their highest level in at least 800,000 years,” severely upsetting this equilibrium.

“The Earth's energy imbalance has increased since its observational record began in 1960, particularly in the past 20 years. It reached a new high in 2025,” the report states. In 2024, the concentration of CO2 in the atmosphere was a whopping 423.9 ppm (parts per million). According to NASA’s measurements, this has further soared to about 428ppm by early 2026. To put the numbers into perspective, at no point during history of Homo sapiens has the atmospheric concentration of CO2 been above 300ppm. During the 1850-1900 baseline period, it was only 278.3ppm. “The concentration in 2024 was 3.5 ppm more than in 2023 and 152% of the estimated pre-industrial concentration (in 1750),” the report states. The planet’s atmosphere currently holds about 3.306 GtCo2 (gigatons of carbon dioxide).

This immense buildup of GHG has been trapping more of the sun’s heat than at any other time since records started. Our energy dependence on fossil fuels like oil, coal and gas is “increasingly disrupting the natural equilibrium and we will live with these consequences for hundreds and thousands of years,” said WMO Secretary-General Celeste Saulo.

And yet, despite the heatwaves, wildfires and deadly storms, humans are currently experiencing only 1% of the total trapped heat—this is the bit that is in the atmosphere. The planet’s land surface has absorbed about 5% of the heat, about 3% is melting mountain glaciers and polar ice, while the global ocean has absorbed an unbelievable 91% of the excess heat. “Ocean heat content reached a new record high in 2025 and its rate of warming more than doubled from 1960-2005 to 2005-2025,” the WMO said.

This energy imbalance is leading to a perfect storm of global disasters. While it is now a certainty that the global average temperature will breach the 1.5 degrees mark, at least temporarily, rising atmospheric heat is impacting global harvests and food security. A hotter ocean is fuelling deadly cyclones while rising ocean acidity is decimating coral reefs and severely affecting marine life. And as polar ice melt and global sea levels rise, the future of coastal cities is under threat.

The Earth’s capacity to hold heat and support a normal climate is, as the UN Secretary-General António Guterres put it, being pushed to the limit. “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,” he said.

Another crucial detail from the report is that global temperature remained high in 2025 despite La Nina conditions. This is a natural climate phenomenon that cools sea surface temperatures in equatorial Pacific Ocean, which in turn affects global wind systems, atmospheric pressure and rainfall. The opposite of this is the El Nino, which sets off a warming effect.

2024’s record breaking heat, when the global average temperature was 1.55 degrees Celsius above pre-industrial levels, occurred during an El Nino cycle. Scientists fear that with similar conditions slated to set in later this year, 2027 may again shatter temperature records as trapped heat builds on El Nino conditions.

While many of the results of prolonged heating is now baked into the Earth’s systems, and will continue to affect us for centuries, there is still a chance to stave off a nightmare scenario of 3-4 degrees of warming by 2100. And the only way to do so is to end our reliance on fossil fuels. “In this age of war, climate stress is also exposing another truth: our addiction to fossil fuels is destabilising both the climate and global security,” Guterres said while commenting on the WMO report. “Today's report should come with a warning label: climate chaos is accelerating and delay is deadly.”