Their analysis demonstrated that in a cyclone, narrow plumes of miles-tall storm clouds can rise so explosively through the atmosphere that they often push into the stratosphere.

Romps and Kuang found that tropical cyclones are twice as likely as other storms to punch into the normally cloud-free stratosphere, and four times as likely to inject ice deep into the stratosphere.

"It is ... widely believed that global warming will lead to changes in the frequency and intensity of tropical cyclones," Romps and Kuang write in Geophysical Research Letters. "Therefore, the results presented here establish the possibility for a feedback between tropical cyclones and global climate."

Typically, very little water is allowed passage through the stratosphere's lower boundary, known as the tropopause. Located some 6 to 11 miles above the Earth's surface, the tropopause is the coldest part of the Earth's atmosphere, making it a barrier tothe lifting of water vapor into the stratosphere -- as air passes slowly through the tropopause, it gets so cold that most of its water vapor freezes out and falls away.

But if very deep clouds, such as those in a tropical cyclone that can rise through the atmosphere at speeds of up to 40 miles per hour, can punch through the tropopause too quickly for this to happen, they can deposit their ice in the warmer overlying stratosphere, where it then evaporates.

"This suggests that tropical cyclones could play an important role in setting the humidity of the stratosphere," Romps and Kuangwrite.

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Editor:Yang Jie