The “O” zone

By: Tarun Vaid We have been talking about it for years now, but little has been done in this regard. The Ozone layer has been protecting us since the atmosphere was formed. It is this ozone layer, which protects us from harmful UV rays of the sun. The sun doesn`t just produce heat and light. It throws out all sorts of other types of electromagnetic radiation, including ultraviolet radiation. Because ultraviolet radiation can damage DNA, it is potentially harmful to most living things, including plants. In the late 1920s the biggest enemy of the ozone layer called cloro-floro-carbons was invented. CFCs were not poisonous and didn`t harm fabrics, plants or people. Companies thought they were great and used them in refrigerators, air conditioners, styrofoam packaging, and spray cans. And this process went on till 1970s, when scientists discovered that those CFCs, which have been released in the air, would float through the troposphere up into the stratosphere. There the UV rays broke them down. And then this chemical hampered the ozone molecules by breaking them up. Thus they created a manmade imbalance in the natural atmosphere. Scientists often refer to the part of the atmosphere, where ozone is most depleted as the `ozone hole`, but it is not really a hole, just a vast region of the upper atmosphere where there is less ozone than elsewhere. The ozone-destroying reactions take place most rapidly only under certain conditions in the stratosphere. These conditions – extreme cold, darkness and isolation, followed by exposure to light – occur over the Polar Regions after the long polar winter has finished and the first spring sun appears. Antarctica is the worst affected area, probably because the air above it is most isolated from the rest of the atmosphere. Ozone-poor air can spread out from the Polar Regions and move to other areas. In addition, direct ozone loss elsewhere is slowly increasing, although it is not occurring at the same rate as over the poles. Unfortunately our bodies can`t detect ultraviolet radiation directly. We can be unaware of the harm it is causing until it is too late – for example, at the end of a day in the sun without adequate protection. The United States National Aeronautics and Space Administration (NASA) found that the hole in the ozone layer had reached its biggest size ever: 28.3 million square kms—larger than Europe and South America combined. The recent study by World Meteorological Organisation (WMO) and the U.N. Environmental Programme (UNEP) shows that the ozone will now take 15 more years to recover, which means that it will now recover in the year 2065. Delayed recovery is a warning that we cannot take the ozone layer for granted and must maintain and accelerate our efforts to phase out harmful chemicals. CFCs are now banned in Australia and USA(and many other countries). Their temporary replacements, the hydrochlorofluorocarbons, are still slightly ozone-depleting, though not to the same extent. An international agreement called the Montreal Protocol limits the production and use of ozone-depleting substances. A slowing down in the rate of ozone loss has been measured, and the concentration of CFCs in the atmosphere is levelling off. If all countries keep to the targets set by the international community in the amendments to the Montreal Protocol, the ozone in the stratosphere should eventually recover. Like the Montreal agreement, Kyoto Protocol also talks about reducing the pollutants like CFCs in the form of greenhouse gases. But unlike Montreal Protocol, Kyoto is only covering 25 percent of the emissions. Instead of aiming at the complete global action necessary to address the problem, as the Montreal Protocol does, Kyoto is delivering just a percent reduction at best in global greenhouse gas emissions over the time of the Protocol, whereas what the world needs by the end of this century is a reduction of 50 to 60 per cent. The world today needs bigger help against ozone depletion. The best help that we can give to it would be awareness.