Left: Ozone in Earth’s stratosphere at an altitude of approximately 12 miles (20 kilometers) in mid-March 2011, near the peak of the 2011 Arctic ozone loss. Red colors represent high levels of ozone, while purple and grey colors (over the north polar region) represent very small ozone amounts. Right: chlorine monoxide – the primary agent of chemical ozone destruction in the cold polar lower stratosphere – for the same day and altitude. Light blue and green colors represent small amounts of chlorine monoxide, while dark blue and black colors represent very large chlorine monoxide amounts. The white line marks the area within which the chemical ozone destruction took place. Image credit: NASA/JPL-Caltech
The protective ozone layer in the Arctic that keeps out the sun’s most damaging rays, ultraviolet radiation, has thinned about 40 percent this winter, a record drop, the U.N. weather agency said Tuesday.
The Arctic’s damaged stratospheric ozone layer isn’t the best known “ozone hole,” that would be Antarctica’s, which forms when sunlight returns in spring there each year…