Rising Damp From Small Comets?

摘要

First, there were the strange, dark spots in the upper atmosphere, seen this spring in ultraviolet images from a satellite. Now comes evidence that the atmosphere has a relatively wet layer 70 to 80 kilometers (km) up. In the standard picture of the atmosphere, water vapor is trapped below 12 km or so by a moisture barrier at the bottom of the stratosphere, keeping the mesosphere--the region between 50 and 90 km--almost bone dry. But last week, a satellite instrument detected signs of as much as 50%more water vapor at those altitudes than is called for by any conventional theory.