Beschreibung:
A region of extreme low ozone values passed over North‐western Europe during November 30, and December 1, 1999. The total ozone values were measured from the ground, with a Brewer Spectrophotometer, and from space with the GOME and TOMS satellite instruments. The ozone sonde measurement and the retrieved GOME ozone profile have shown that the main reduction in the ozone column occurred between the ozone maximum (22 km) and the tropopause. The low temperatures found in the stratosphere during this event have significant consequences for the ozone retrieval algorithm, both for satellite retrievals and for the Brewer measurements.