A team of scientists from the Centre of Excellence for Climate Extremes at the Australian Research Council revealed that Earth’s cloud cover is significantly decreasing, a trend that could be intensifying global warming and contributing to the historical temperature records recorded worldwide.
The study, published in the journal Geophysical Research Letters, analyzed satellite data from the last two decades and concluded that between 1.5% and 3% of storm cloud areas have been disappearing each decade since 2000. This cloud contraction is related to changes in wind patterns, the shift of storm systems towards the poles, and the expansion of the tropics—widely documented effects of climate change.
Fewer clouds, more absorbed solar radiation
The decrease in clouds means that less sunlight is reflected back into space, increasing the absorption of radiation by the Earth’s surface and oceans. This dynamic enhances the warming effect of greenhouse gases already present in the atmosphere.
“We have long known that changes in atmospheric circulation affect cloud formation, but we now demonstrate that these alterations are significantly modifying the planet’s energy balance”, explained Professor Christian Jakob, study co-author and director of the center, in a statement from Monash University.
A wake-up call for urgent climate action
The researchers view this phenomenon as a key piece to understand the recent accelerated warming, and warn that predicting more accurately where clouds will form and their ability to reflect light will be crucial to project the future pace of climate change.
“It’s a wake-up call. Understanding how and why cloud cover changes is essential to anticipate future scenarios and design effective mitigation strategies”, Jakob concluded.
