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Stratospheric Ozone and UV Radiation
Environment Canada is the WMO's gardian of ozone stratospheric measurements. Environment Canada provides the most recent full-day total ozone maps of the stratospheric ozone levels for Canada in near real time. For evaluation purposes, archived maps of the northern hemisphere could also be found. Designing the map for the period of your choice is possible.
These maps are complemented by global maps of CFC11 and CFC12 annual percentages, global map of UV-B and the trend of ozone in the Canadian Troposphere.
Maps of Total Ozone for July 1980 (40 KB gif image) and for July 1998 (41 KB gif image)
Source: Vitali Fioletov, 2000. Pers. Comm. Experimental Studies Division, Meteorological Service of Canada, Environment Canada.Annual CFC percentage: CFC11 (10 KB gif image)
Source: Global Emission Inventory Activity (1986)Annual CFC percentage: CFC12 (10 KB gif image)
Source: Global Emission Inventory Activity (1986)Global UV Intensity Maps
Source: CIESIN, SEDAC, NASANASA global erythemal UV exposure (27 KB gif image)
Source: NASA (2000)
This is an example of TOMS global image of daily erythemal UV exposure. Ultraviolet radiation exists to the left of the visible spectrum and is divided into three components (UV-A, UV-B and UV-C). UV-B (290-320 wavelengths) is the most dangerous form of UV radiation that can reach ground level. Atmospheric ozone shields life at the surface from most of the harmful components of solar radiation. Chemical processes in the atmosphere can effect the level of protection provided by the ozone in the upper atmosphere. This thinning of the atmospheric ozone in the stratosphere leads to elevated levels of UV-B at ground level and increases the risks of DNA damage in living organisms. http://toms.gsfc.nasa.gov/Canadian tropospheric ozone trend (314 KB jpg image) small version (36 KB jpg image)
Source: Tarasick, D. 2000. Pers. Comm. Experimental Studies Division, Meteorological Service of Canada, Downsview, Canada