WMO: Energy Imbalances, Global Warming & Extreme Weather

The Earth’s climate system is undergoing rapid and unprecedented change, as confirmed by the World Meteorological Organization (WMO) in its report, State of the Global Climate 2025.

Recent findings show that GHG concentrations are driving continued warming across the atmosphere, oceans and ice systems. 

The years 2015–2025 have been identified as the eleven hottest on record, highlighting a clear and accelerating trend. 

These changes are not short-term anomalies but long-lasting disruptions that are likely to impact the planet for centuries to come.

A planet out of balance

One of the most critical insights from the WMO report is that the Earth’s energy balance has been disrupted. 

Under natural conditions, incoming solar energy is balanced by outgoing heat, but increasing concentrations of GHG have reduced the amount of energy escaping into space. 

This has created what is known as an “energy imbalance", causing excess heat to accumulate within the Earth system. 

According to WMO, since 1960 this imbalance has been steadily increasing, with particularly sharp rises over the past two decades.

As a result, the planet is warming at an accelerating rate, rather than stabilising.

“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,” says António Guterres, UN Secretary-General.

“Humanity has just endured the eleven hottest years on record. When history repeats itself eleven times, it is no longer a coincidence. It is a call to act."

Around 91% of it is absorbed by the ocean, making it the primary buffer against atmospheric warming with smaller proportions being stored in land (about 5%), ice (3%) and the atmosphere (1%). 

While this distribution slows immediate temperature increases on land, it leads to long-term consequences such as ocean warming, melting ice sheets and rising sea levels. 

The imbalance demonstrates that climate change is not only about temperature increases but about a systemic shift in how energy flows through the planet.

Rising temperatures and record heat

Global temperatures have risen significantly, with 2025 recorded as one of the warmest years in a 176-year observational record, according to WMO.

The global mean near-surface temperature reached approximately 1.43°C above pre-industrial levels. 

Even slight increases at this scale represent substantial changes in climate patterns and environmental stability. 

The fact that the past 11 years are the warmest on record highlights a persistent and intensifying trend rather than natural variability.

This warming is closely linked to GHG concentrations, particularly CO₂, methane and nitrous oxide. 

In 2024, CO₂ levels reached their highest concentration in at least two million years. 

Human activities such as fossil fuel combustion and deforestation are the primary drivers behind this increase. 

These gases trap heat in the atmosphere, reinforcing the greenhouse effect and amplifying global warming.

The consequences of rising temperatures extend far beyond simple heat increases. 

They contribute to more frequent and intense extreme weather events, including heatwaves, droughts, floods and storms.

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These events disrupt ecosystems, damage infrastructure and threaten human lives and livelihoods. 

The warming climate also exacerbates existing inequalities, as vulnerable communities are often the most affected.

“And 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,” says António.

“Today’s report should come with a warning label: climate chaos is accelerating and delay is deadly.”

Oceans, ice and sea-level rise

The ocean plays a central role in the climate system, absorbing both heat and CO₂. 

“Scientific advances have improved our understanding of the Earth’s energy imbalance and of the reality facing our planet and our climate right now,” says Celeste Saulo, WMO Secretary-General. 

“Human activities are increasingly disrupting the natural equilibrium and we will live with these consequences for hundreds and thousands of years.”

Over the past two decades, the ocean has absorbed energy equivalent to around eighteen times the annual human energy use each year, says the report. 

This has led to record-high ocean heat content, with each of the past nine years setting new records. 

While this reduces immediate atmospheric warming, it has severe consequences for marine ecosystems, including biodiversity loss and coral bleaching.

Ocean warming also contributes to sea-level rise. 

As water warms, it expands and combined with melting glaciers and ice sheets, this has caused global sea levels to increase. 

WMO highlights that since 1993, sea levels have risen by approximately 11 centimetres, with the rate of increase accelerating in recent years. 

This rise threatens coastal communities through flooding, erosion and saltwater intrusion into freshwater systems.

At the same time, ice loss is accelerating. 

Glaciers have experienced some of their most significant mass losses on record, with eight of the ten worst years occurring since 2016. 

Arctic and Antarctic sea ice levels are also at historic lows, reducing the Earth’s ability to reflect sunlight and further amplifying warming. 

These changes highlight the interconnected nature of the climate system, where shifts in one area trigger cascading effects across the planet.

Impacts on ecosystems, health and society

Climate change is not only an environmental issue but also a social and economic one. 

Extreme weather events have already caused widespread disruption, affecting millions of people and costing billions of dollars annually. 

These events can trigger food insecurity by damaging crops and disrupting agricultural systems. 

“On a day-to-day basis, our weather has become more extreme,” says Celeste.

“In 2025, heatwaves, wildfires, drought, tropical cyclones, storms and flooding caused thousands of deaths, impacted millions of people and caused billions in economic losses. 

“WMO’s State of the Global Climate report seeks to inform decision-making. 

“It is in keeping with the theme of World Meteorological Day because when we observe today, we don’t just predict the weather, we protect tomorrow. 

“Tomorrow’s people. Tomorrow’s planet.”

In turn, this can lead to displacement, migration and increased pressure on already vulnerable communities.

The report also highlights the growing impact of climate change on human health. 

Rising temperatures and changing rainfall patterns are influencing the spread of diseases such as dengue, now one of the fastest-growing mosquito-borne illnesses globally. 

Heat stress is another major concern, with more than one-third of the global workforce exposed to dangerous conditions each year. 

These impacts reduce productivity, threaten livelihoods and place additional strain on healthcare systems.

Furthermore, the cascading effects of climate change extend to ecosystems and biodiversity. 

Ocean acidification, caused by the absorption of CO₂, is altering marine chemistry and harming organisms such as shellfish and corals. 

On land, shifting temperatures and precipitation patterns are affecting habitats and species distribution. 

These interconnected impacts demonstrate that climate change is a complex, multi-dimensional challenge requiring urgent and coordinated action.