Long-term ozone trends derived from the 16-year combined Nimbus 7/Meteor 3 TOMS Version 7 record

Ozone measurements from the Nimbus 7 TOMS instrument, which operated from November 1978 through early May 1993, have been extended through December 1994 using data from the TOMS instrument on‐board the Russian Meteor 3 satellite. Both TOMS data records have recently been recalibrated, and then reprocessed using the Version 7 retrieval algorithm. Long‐term trend estimates obtained from a multiple regression analysis show ozone losses in the extended data record similar to those reported in previous studies using Version 6 TOMS and SBUV data, and ground‐based Dobson data. Ozone continues to decline through the end of 1994, with the most significant ozone losses occurring in the high southern latitudes during October (−20% per decade) and in the northern mid‐ to high‐latitudes during March/April (−6 to −8% per decade). There is no significant ozone trend in the tropics. Annual‐average trends derived from the Nimbus 7 Version 7 data are 0–2.5% per decade less negative than those derived over the same time period using Version 6 data.