Anomalous temperature averages in Antarctica are illustrated in an undated illustration. The ozone layer is showing signs of recovering, thanks to a drop in ozone-depleting chemicals, but it is unlikely to stabilize at pre-1980 levels, researchers said on Wednesday. Image Credit: NASA/Handout/Reuters
Ozone measurements are improving and some scientists are very pleased.
Excerpts from Reuters via Yahoo! News -
Ozone layer shows signs of recovery: scientists
By Patricia Reaney - Wed May 3, 1:08 PM ET
LONDON (Reuters) - The ozone layer is showing signs of recovering, thanks to a drop in ozone-depleting chemicals, but it is unlikely to stabilize at pre-1980 levels, researchers said on Wednesday.
Depletion of the earth's protective ozone layer is caused by the chemical action of chlorine and bromine released by man-made chlorofluorocarbons (CFCs), which are used in aerosol sprays and cooling equipment.
Ozone-depleting chemicals were banned by the 1987 Montreal Protocol which has now been ratified by 180 nations.
"We now have some confidence that the ozone layer is responding to the decreases in chlorine levels in the atmosphere due to the leveling off and decrease of CFCs," said Dr Betsy Weatherhead, of the University of Colorado in Boulder.
"Not only is the ozone layer getting better, we feel it is due to the Montreal Protocol," she added in an interview.
Despite the signs of recovery, Weatherhead, who reported the findings in the journal Nature, said people should still protect themselves from harmful ultraviolet rays.
Shifting temperatures, greenhouse gases, nitrous oxide (N20) and atmospheric dynamics, which can influence ozone levels, are going to change in the future, they added.
"Therefore we really don't think ozone is going to stabilize back to its pre-ozone-depleting-substance levels," Weatherhead said.
Volcanic activity on Earth also has an impact. The 1993 Mount Pinatubo eruption in the Philippines caused ozone levels to backslide for several years, according to the researchers.
Really, do you think that the Montreal Protocol success claim is valid in the face of such little evidence??
The truth is that this is a big system, Earth. This system has been around for millions and millions of years, yet WE humans feel that our little agreement is netting returns in 19 years, even though Mt. Pinatubo caused the ozone levels to "backslide".
Exactly how long have WE humans been able to measure changes in the ozone layer? Excuse me for being skeptical. Say 30 years, maybe? Okay!