Global Warming Intensified by Decline in Low Clouds, New Study Finds

The year 2023 marked the hottest in recorded history. Despite understanding the roles of greenhouse gas emissions and El Niño in driving global temperatures upward, scientists struggled to account for the extraordinary heat increase.

Now, a new study published in Science suggests a key missing factor: a decline in low-lying clouds over oceans.

How Fewer Low Clouds Are Driving Rising Temperatures

Low clouds, often called Earth's "sunscreen," play a crucial role in reflecting sunlight back into space. A reduction in these clouds allows more sunlight to reach the Earth's surface, intensifying warming, CNN said.

This process, known as "albedo," measures the planet's ability to reflect solar energy. As fewer clouds form, Earth's albedo decreases, leading to accelerated heating.

The study analyzed NASA satellite data, weather observations, and climate models to uncover a decade-long decline in low cloud cover.

This drop reached record lows in 2023, particularly over regions like the North Atlantic Ocean. As a result, Earth absorbed more solar radiation, contributing to the unexpected rise in global temperatures.

The reasons behind the declining cloud cover remain complex. Scientists point to several possibilities. One is a reduction in sulfur emissions from ships.

While this regulatory change benefits air quality and human health, it may inadvertently weaken cloud formation. Sulfur particles help clouds form and reflect sunlight more effectively.

Another potential factor is natural climate variability, such as shifts in ocean temperatures, which can disrupt the formation of low clouds.

However, a more concerning possibility is that global warming itself is reducing cloud formation. Warmer surface temperatures can thin or dissipate low clouds, creating a feedback loop where warming causes fewer clouds, which in turn amplifies warming further.

Urgent Need for Action as Cloud Decline Threatens Climate Targets

Experts caution that if this feedback loop is significant, future global warming could be more intense than currently projected, according to NBC News.

This has serious implications for climate sensitivity—how much the planet warms in response to greenhouse gas emissions.

Current projections may underestimate the pace and scale of warming, potentially bringing humanity closer to surpassing climate targets like those set in the Paris Agreement.

While the study raises alarms, it also highlights the need for more research. Clouds remain one of the most challenging components of the climate system to understand and predict. Determining how cloud behavior will evolve in a warming world is critical for refining climate models and preparing for future changes.

The findings suggest the urgency of reducing greenhouse gas emissions to mitigate the accelerating impacts of climate change. With Earth's natural cooling systems under threat, proactive measures are essential to limit global temperature rise and prevent catastrophic consequences.