Cooling Upper Atmosphere Has Scientists ‘Very Worried’

New research has confirmed that the same gases responsible for climate change are cooling the Earth’s upper atmosphere, raising concerns about effects on orbiting satellites, ozone, and weather—and providing “incontrovertible” evidence of the human influence on global temperatures. The power of greenhouse gases to warm the troposphere is widely acknowledged, but their cooling effect on upper levels—like the stratosphere—is less well known. They are “driving dramatic changes scientists are just now beginning to grasp.”The rapid cooling is causing the stratosphere to contract, which in turn makes upper levels less dense. Upper atmospheric changes could also weaken the ozone layer and reduce the protection it gives humans from harmful solar radiation. There is also potential for changes in the upper atmosphere to affect weather closer to home.