Columbia University Scientists Explain the Cause of Stratospheric Cooling

Earth's surface is warming, but the stratosphere has cooled for decades – and now Columbia University scientists have finally explained what drives this process. A new study focuses on the interaction between carbon dioxide and infrared radiation in the upper layers of the atmosphere. The discovery helps us better understand the mechanisms of human-caused climate change.

Columbia University scientists have made a breakthrough in climate research, identifying the precise physical mechanism that causes the ongoing cooling of the stratosphere. While the Earth's surface and lower atmosphere continue to warm, the upper stratosphere has experienced the opposite trend for decades – a phenomenon considered one of the most important indicators of human-caused climate change.

Why is the stratosphere cooling?

Until now, scientists have measured this paradox, but the exact mechanism remained unclear. A new Columbia University study explains how carbon dioxide and infrared radiation interact in a complex way in the upper atmosphere. This very interaction is the key factor that explains the drop in stratospheric temperature.

The dual role of CO2 in climate

The main conclusion of the study is that carbon dioxide does not function the same way in different layers of the atmosphere. In the lower layers, it acts as a greenhouse gas, trapping heat, but in the upper layers, it radiates heat into space, causing cooling. The more CO2 accumulates in the atmosphere, the stronger this dual effect becomes – the surface warms and the stratosphere cools.

The discovery is an important step in refining climate models. According to the scientists, a better understanding of the mechanism will help predict future climate changes more accurately and provides a new perspective for assessing the impact of human activity on the entire atmosphere as a whole.