In Geneva, Switzerland on Wednesday scientists working with two United Nations organizations reported that a reduction of ozone depleting substances (ODS) due to steps taken under the 1987 Montreal Protocol has had a positive effect in helping the Earth’s ozone layer to start its recovery process, albeit slowly, towards levels not seen since 1980. However, scientists also cautioned that rising anthropogenic carbon dioxide and methane levels in the atmosphere are also in part responsible for the ozone layer’s recovery.
As reported on the UNEP website News Center, World Meteorological Organization Secretary-General Michel Jarraud said of the news, “International action on the ozone layer is a major environmental success story. This should encourage us to display the same level of urgency and unity to tackle the even greater challenge of climate change. This latest assessment provides solid science to policy-makers about the intricate relationship between ozone and climate and the need for mutually-supportive measures to protect life on earth for future generations.”
The “Assessment for Decision-Makers, Scientific Assessment of Ozone Depletion: 2014” was released in a joint study by the World Meteorological Organization (WMO) and the UN Environment Program (UNEP) with input from the U.S. National Oceanic and Atmospheric Administration (NOAA), the U.S. National Aeronautics and Space Administration (NASA) and the European Commission. This assessment is a preliminary report; the final report will be released next year.
According to UNEP, the key findings of the report are,
- “Actions taken under the ‘Montreal Protocol on Substances that Deplete the Ozone Layer’ are enabling the return of the ozone layer to benchmark 1980 levels.
- The climate benefits of the Montreal Protocol could be significantly offset by projected emissions of HFCs (hydrofluorocarbons) used to replace ozone depleting substances.
- The annual Antarctic ozone hole has caused significant changes in Southern Hemisphere surface climate in the summer.
- CO2, nitrous oxide and methane will have an increasing influence on the ozone layer.”
If the ozone layer recovers according to scientific prediction, in general it may recover to its 1980 levels by the middle of this century. However, the Antarctic ozone hole will most likely take more time to recover. It is important to note that this report clearly indicated that while the reduction of ozone has stopped, the increase in ozone has only slightly begun. Even so, this reversal in itself is a significant sign of humankind’s ability to solve environmental problems created by humankind.
There are areas of concern for continued ozone layer recovery as it relates to other climate benefits. While HFCs are not ODSs, their continued and increased use adds to man-made carbon dioxide within in the atmosphere. In addition, nitrous oxide, one of the three major man-made greenhouse gases increasing in the atmosphere due to human activity is an ODS and has yet to be banned. Furthermore, successful steps to stop and possibly reverse the emissions of man-made CO2 and methane, while necessary to halt or at least minimize the disastrous effects of climate change on the planet, may in turn actually slow the ozone recovery process.
According to Reuters, UNEP has stated that the Montreal Protocol will prevent up to 2 million cases of skin cancer every year worldwide by 2030. The ozone layer helps to protect all life on Earth from the damaging effects of ultraviolet radiation from the sun.