Most research on cloud responses to climate change has focused on oceans, leaving mountain clouds poorly understood. A new study in AGU Advances used satellite observations and climate data from 2003 to 2022 to track cloud fraction, top temperature, and height over the Tibetan Plateau, European Alps, Andes, Appalachians, and Rockies, plus their adjacent lowlands.
The researchers found that clouds over most of these mountain regions gained warm-liquid and ice phases, while vertical development was suppressed and supercooled clouds became rarer. Ice cloud tops over mountains rose and cooled two to four times faster than those over nearby lowlands, indicating a stronger and more rapid response to warming.
Supercooled clouds behaved differently depending on elevation. Over lowlands and lower mountains, their tops warmed and descended, suggesting stunted vertical growth. But over the highest ranges—the Tibetan Plateau and Andes—supercooled clouds cooled and ascended. The authors attribute this to different regional mechanisms: stronger lower-atmosphere warming destabilizing the vertical profile over the Tibetan Plateau, and increased atmospheric moisture over the Andes.
The findings highlight that high-elevation clouds are not just changing more strongly but also in distinct ways from other regions. The authors call for further research into how these icy cloud changes affect Earth's radiative energy balance, which could improve regional climate models and water-resource predictions for the hundreds of millions of people who depend on mountain runoff.