Articles | Volume 17, issue 19
Technical note
11 Oct 2017
Technical note |  | 11 Oct 2017

Technical note: The US Dobson station network data record prior to 2015, re-evaluation of NDACC and WOUDC archived records with WinDobson processing software

Robert D. Evans, Irina Petropavlovskikh, Audra McClure-Begley, Glen McConville, Dorothy Quincy, and Koji Miyagawa

Abstract. The United States government has operated Dobson ozone spectrophotometers at various sites, starting during the International Geophysical Year (1 July 1957 to 31 December 1958). A network of stations for long-term monitoring of the total column content (thickness of the ozone layer) of the atmosphere was established in the early 1960s and eventually grew to 16 stations, 14 of which are still operational and submit data to the United States of America's National Oceanic and Atmospheric Administration (NOAA). Seven of these sites are also part of the Network for the Detection of Atmospheric Composition Change (NDACC), an organization that maintains its own data archive. Due to recent changes in data processing software the entire dataset was re-evaluated for possible changes. To evaluate and minimize potential changes caused by the new processing software, the reprocessed data record was compared to the original data record archived in the World Ozone and UV Data Center (WOUDC) in Toronto, Canada. The history of the observations at the individual stations, the instruments used for the NOAA network monitoring at the station, the method for reducing zenith-sky observations to total ozone, and calibration procedures were re-evaluated using data quality control tools built into the new software. At the completion of the evaluation, the new datasets are to be published as an update to the WOUDC and NDACC archives, and the entire dataset is to be made available to the scientific community. The procedure for reprocessing Dobson data and the results of the reanalysis on the archived record are presented in this paper. A summary of historical changes to 14 station records is also provided.

Short summary
The record of the total ozone column (TOC) from stations using the Dobson ozone spectrophotometer is one of the longest geophysical records in existence. Recent adoption of a new data processing scheme, with improved results prompted a complete reprocessing of the historical record from these NOAA/NDACC sites. As the original record of TOC from these stations are used for trend analysis and satellite verification, the scientific community should be aware of the changes in the new data set.
Final-revised paper