Ozone symposium and assessment
Twenty-five years ago in May, scientists with the British Antarctic Survey reported that the springtime stratospheric ozone layer over the Antarctic was thinning dramatically. In the years since then, ESRL scientists have been extensively involved in understanding the reasons for that decline, tracking levels of the chemicals that deplete stratospheric ozone, and calculating the effectiveness of international policies to allow ozone layer recovery.
Three of those ESRL researchers traveled to the University of Cambridge this spring, to celebrate the 25th anniversary of the publication describing the discovery of ozone depletion, and to honor the authors of that paper—Joe Farman, Brian Gardiner, and Jonathan Shanklin.
Susan Solomon (Chemical Sciences Division, CSD) spoke about past and future ozone depletion. David Fahey (CSD) described how an international treaty to regulate ozone-depleting chemicals has also benefitted climate. A.R. Ravishankara (CSD Director) attended the symposium; he was at nearby Oxford University, serving as the distinguished Hinshelwood Lecturer.
ESRL scientists from the Global Monitoring and Chemical Sciences divisions are helping to co-author the 2010 Scientific Assessment of Ozone Depletion, conducted under the auspices of the World Meteorological Organization and the United Nations Environment Programme. The last assessment came out in 2006; the executive summary of the 2010 assessment will be released in July.
A.R. Ravishankara is co-chair of the 2010 assessment, and coordinating lead authors include John Daniel (CSD), Steve Montzka (GMD), and David Fahey (CSD). Christine Ennis (CSD) is coordinating editor, and other ESRL staff are serving as lead authors, coauthors, reviewers, and in other roles.
Image: Ozone minimum over Antarctica in September 2009, courtesy of NASA