Global Atmospheric OCS Trend Analysis From 22 NDACC Stations


James W. Hannigan, National Center for Atmospheric Research
Ivan Ortega, National Center for Atmospheric Research
Shima Bahramvash Shams, National Center for Atmospheric Research
Thomas Blumenstock, Karlsruher Institut für Technologie
John Elliott Campbell, University of California, Santa Cruz
Stephanie Conway, University of Toronto
Victoria Flood, University of Toronto
Omaira Garcia, Meteorological State Agency of Spain
David Griffith, Faculty of Science, Medicine and Health
Michel Grutter, Universidad Nacional Autónoma de México
Frank Hase, Karlsruher Institut für Technologie
Pascal Jeseck, Sorbonne Universite
Nicholas Jones, University of Wollongong
Emmanuel Mahieu, Université de Liège
Maria Makarova, Saint Petersburg State University
Martine De Mazière, Royal Belgian Institute for Space Aeronomy
Isamu Morino, National Institute for Environmental Studies of Japan
Isao Murata, Tohoku University
Toomo Nagahama, Nagoya University
Hideaki Nakijima, National Institute for Environmental Studies of Japan
Justus Notholt, Universität Bremen
Mathias Palm, Universität Bremen
Anatoliy Poberovskii, Saint Petersburg State University
Markus Rettinger, Karlsruher Institut für Technologie
John Robinson, National Institute for Water and Atmosphere
Amelie N. Röhling, Karlsruher Institut für Technologie
Matthias Schneider, Karlsruher Institut für Technologie
Christian Servais, Université de Liège
Dan Smale, National Institute for Water and Atmosphere
Wolfgang Stremme, Universidad Nacional Autónoma de México

Publication Name

Journal of Geophysical Research: Atmospheres


Carbonyl sulfide (OCS) is a non-hygroscopic trace species in the free troposphere and a large sulfur reservoir maintained by both direct oceanic, geologic, biogenic, and anthropogenic emissions and the oxidation of other sulfur-containing source species. It is the largest source of sulfur transported to the stratosphere during volcanically quiescent periods. Data from 22 ground-based globally dispersed stations are used to derive trends in total and partial column OCS. Middle infrared spectral data are recorded by solar-viewing Fourier transform interferometers that are operated as part of the Network for the Detection of Atmospheric Composition Change between 1986 and 2020. Vertical information in the retrieved profiles provides analysis of discreet altitudinal regions. Trends are found to have well-defined inflection points. In two linear trend time periods ∼2002 to 2008 and ∼2008 to 2016 tropospheric trends range from ∼0.0 to (1.55 ± 0.30%/yr) in contrast to the prior period where all tropospheric trends are negative. Regression analyses show strongest correlation in the free troposphere with anthropogenic emissions. Stratospheric trends in the period ∼2008 to 2016 are positive up to (1.93 ± 0.26%/yr) except notably low latitude stations that have negative stratospheric trends. Since ∼2016, all stations show a free tropospheric decrease to 2020. Stratospheric OCS is regressed with simultaneously measured N2O to derive a trend accounting for dynamical variability. Stratospheric lifetimes are derived and range from (54.1 ± 9.7)yr in the sub-tropics to (103.4 ± 18.3)yr in Antarctica. These unique long-term measurements provide new and critical constraints on the global OCS budget.

Open Access Status

This publication is not available as open access





Article Number


Funding Number


Funding Sponsor

National Science Foundation



Link to publisher version (DOI)