Meteorologist Jeff Masters reports on the record cold stratosphere:
Global temperatures in the lower stratosphere, where the bulk of Earth’s protective ozone layer lies, were at their coldest levels on record during June, according to both the University of Alabama and RSS, Inc. This is the second consecutive month of record cold in the stratosphere. Global warming theory predicts that in order to counter-balance the large amount of warming that occurs in the lower atmosphere near the surface when heat-trapping gases such as carbon dioxide are released into the air, the stratosphere must cool. Thus, a record cold stratosphere is consistent with global warming. However, the majority of the stratospheric cooling that has occurred since the 1990s is probably due to destruction of ozone by chlorine-containing gases like CFCs. Ozone strongly absorbs solar energy, warming the air around it, so if there is less ozone around, there will be less absorption of solar energy and a thus a cooler stratosphere.
Earlier this year, the World Meteorological Organization announced that depletion of the ozone layer—the shield that protects life on Earth from harmful levels of ultraviolet rays—reached an unprecedented level over the Arctic this spring because of the continuing presence of ozone-depleting substances in the atmosphere, and a very cold winter in the stratosphere. The Arctic ozone declined 40% between December and March.
Masters also mentions the heat wave should stick around another week, if not longer.