The first WMO 2010-Antarctic Bulletin is already available (issued on August 27)
The Secretariat of the World Meteorological Organization issues bulletins containing information on the state of the ozone layer in the Antarctic at roughly two week intervals from August to November. The bulletins are based on data provided by WMO Members which operate ozone monitoring stations in the southern hemisphere and satellites to observe ozone globally. Data from the Antarctic Network of NILU radiometers, managed by the Izaña Atmospheric Research Center (AEMET), contributes to the WMO Antarctic bulletins. The first bulletin issued in 2010 is now available. The satellite observations indicate that the area where total ozone is less than 220 DU (“ozone hole area”) is low compared to recent years. However, the onset of ozone depletion varies considerably from one year to the next, depending on the position of the polar vortex and availability of daylight after the polar night. Measurements with ground based instruments and with balloon sondes show first signs of ozone depletion at some sites located close to the vortex edge. It is still too early to give a definitive statement about the development of this year’s ozone hole and the degree of ozone loss that will occur. This will, to a large extent, depend on the meteorological conditions. However, the drop in the occurrence of polar stratospheric clouds since the middle of July and the comparatively small mixing ratios of chlorine monoxide point towards a relatively small ozone hole in 2010.
Figure 7 of the WMO bulletin. In blue colors, relatively low total column ozone values.
To know more about the sate-of the art of the ozone holes in previous years you can download the poster with overview of the ozone holes from 2003-2009. This poster was presented at the General Assembly of the European Geosciences Union in Vienna on 3 May 2010. The Izana Atmospheric Research Center contributed in this summary together with some meteorological services, research institutions and space agencies.
Click on the poster to download a pdf version.
