The World Meteorological Organization (WMO) has reported that the ozone hole over the South Pole in 2008 is larger than in 2007. On the occasion of the International Day for the Preservation of Ozone Layer, Secretary General of the United Nations, Mr. Ban Ki-moon, stated “After decades of chemical attack, it may take another 50 years or so for the ozone layer to recover fully. As the Montreal Protocol has taught us, when we degrade our environment too far, nursing it back to health tends to be a long journey, not a quick fix.”

Routine ozone measurements in all parts of the world using surface-based spectrophotometers, balloon-borne sensors, aircraft and satellites have been made by the National Meteorological and Hydrological Services of WMO members and partners worldwide since the 1950s. Thirty years later, comprehensive measurements started under coordination of the WMO Global Atmosphere Watch (GAW). These measurements have been critical to the series of Scientific Assessments of Ozone Depletion published since the mid-1980s by WMO and the Ozone Secretariat of the United Nations Environment Programme documenting progress made under the Vienna Convention for the Protection of the Ozone Layer. The most recent of these assessments came out in the spring of 2007, and the work on the next ozone science assessment will begin in the middle of 2009.

At the end of August 2008, WMO released the first of its 2008 series bi-weekly Antarctic Ozone Bulletin on the current state of stratospheric ozone in the Antarctic. These bulletins use provisional data from WMO/GAW stations operated within or near the Antarctic, where the most regular and dramatic decreases in ozone occur. According to the latest bulletin, the vortex is presently more circular than at the same time last year. This has led to an onset of ozone depletion that is close to the 1979-2007 average and somewhat later than last year, when the vortex was more elongated and more exposed to sunlight. The meteorological conditions observed so far could indicate that the 2008 ozone hole will be smaller than the 2006 hole but larger than the 2007 one. WMO is the United Nations’ authoritative voice on weather, climate and water. Contact: Ms. Carine Richard-Van Maele, Chief, Communications and Public Affairs, World Meteorological Organization, Switzerland. Tel: +41 (22) 7308 315; Or Ms. Gaelle Sevenier, Press Officer, World Meteorological Organization, Switzerland. Tel: +41 (22) 7308 417.

Source: www.wmo.int

A new Canadian study reveals that cosmic rays, and not CFCs, are the main cause behind ozone depletion in the earth’s atmosphere. The study also predicts that the largest ozone hole – larger than the combined size of the United States and Canada – will occur over Antarctica. Prof. Qing-Bin Lu, a professor of physics and astronomy at the University of Waterloo and a specialist in the study of ozone depletion, states that his study belies the two-decade-old theory that the earth’s ozone layer is being depleted by chlorine atoms produced by sunlight-induced destruction of CFCs in the atmosphere. On the contrary, Prof. Lu said, more and more evidence points to a new theory that cosmic rays – energy particles that originate in space – play a major role in ozone destruction.

According to Prof. Lu data from several sources, including satellites of the National Aeronautics and Space Administration (NASA), confirmed a strong link between cosmic ray intensity and ozone depletion. Prof. Lu added that lab measurements also demonstrated a mechanism by which cosmic rays cause drastic reactions of ozone depleting chlorine inside clouds over Antarctica. Satellite data from 1980 to 2007, covering two full 11-year solar cycles, also demonstrated a significant link between cosmic rays and ozone depletion. “This finding, combined with laboratory measurements, provides strong evidence of the role of cosmic-ray driven reactions in causing the ozone hole and resolves the mystery of why a large discrepancy between the sunlight-related photochemical model and the observed ozone depletion exists,” states Prof. Lu.

Source: www.sify.com