Earth's Energy Imbalance Doubles in Two Decades, New Study Reveals

A recent study highlights a critical shift in Earth's energy balance, revealing that the energy imbalance has more than doubled over the past two decades. This alarming trend is detailed in research conducted by a team of scientists led by Professor Steven Sherwood from the Climate Change Research Centre at the University of New South Wales (Sherwood et al., 2023). The study, published in the Journal of Climate Dynamics on June 30, 2025, indicates that the average energy imbalance has increased from approximately 0.6 watts per square meter (W/m²) in the mid-2000s to about 1.3 W/m² in recent years. This significant rise suggests that the rate at which energy is accumulating near the Earth's surface has accelerated, with profound implications for climate change.

The concept of Earth's energy budget is akin to managing a bank account, where energy input from the Sun must balance the energy output back into space. However, the burning of fossil fuels has added over two trillion tonnes of carbon dioxide and other greenhouse gases to the atmosphere, exacerbating the greenhouse effect and preventing heat from escaping. While some of this excess heat contributes to warming land surfaces and melting ice, approximately 90% of it is absorbed by the oceans, which have a high capacity for heat storage (Meyssignac et al., 2023).

In the past century, the average global surface temperature has risen by 1.3 to 1.5 degrees Celsius. This temperature increase underscores the urgency of addressing climate change, particularly as federal funding uncertainties in the United States jeopardize critical climate monitoring efforts. NASA has been instrumental in collecting long-term observational data, which is essential for understanding changes in Earth's energy balance (NASA, 2023).

Tracking the energy budget involves two primary methodologies: direct measurements of solar energy entering and leaving the atmosphere, and monitoring temperature changes in the oceans and atmosphere through robotic floats deployed since the 1990s. Both methods indicate that the energy imbalance is growing far more rapidly than climate models had previously predicted (Mauritsen et al., 2023).

Research findings suggest that changes in cloud cover may be a contributing factor to this rapid energy imbalance. The shrinking area of highly reflective white clouds, coupled with an increase in less reflective cloud types, has altered the Earth's capacity to reflect solar energy. While the precise reasons for these changes remain uncertain, some researchers propose that regulatory efforts to reduce sulfur emissions from shipping fuel may have inadvertently impacted cloud reflectivity (Sherwood et al., 2023).

The implications of this doubling energy imbalance are profound, raising concerns about the potential for more extreme climate events—such as intense heatwaves, droughts, and marine heatwaves—over the coming decade. Experts warn that these findings suggest recent hot years are not anomalies, but rather indications of an accelerating warming trend (Sherwood et al., 2023; Meyssignac et al., 2023).

In conclusion, the findings of this study emphasize the necessity for immediate action to mitigate greenhouse gas emissions and improve climate monitoring efforts. As the research team advocates, halting the routine burning of fossil fuels and phasing out activities that contribute to emissions will be vital in addressing this escalating crisis. The ongoing threat posed by funding cuts to climate monitoring underscores the need for sustained investment in scientific research and data collection to effectively combat climate change and protect global ecosystems (Mauritsen et al., 2023).