Ozone Hole July 2023
The total ozone maps are based on ground-based measurements
available from the World
Ozone and Ultraviolet Radiation Data Centre.
Preliminary near real-time data from ground-based observations
were also used for the most recent maps. Total ozone values are
given in Dobson
Units.
The numbers represent observations taken from ground stations
situated at the bottom left corner of the number.
Maps of deviations represent total ozone deviations from the 1978-1988
level estimated using Total
Ozone Mapping Spectrometer (TOMS) data for all
areas except the Antarctic and from the pre-1980 level estimated
using Dobson data over the Antarctic.
Over areas with poor data coverage adjustments are made according to TOMS on
Nimbus-7, Meteor-3, ADEOS and Earth Probe satellites. Over the polar
night area Dobson and Brewer moon observations and/or NOAA's
TIROS Operational Vertical Sounder (TOVS) satellite
data are used. TOVS data are also used when the more reliable TOMS
data are not available. The mapping algorithm is similar to those
used by the WMO
Ozone Mapping Centre.
