Nitrous oxide in the surface layer of the tropical North Atlantic Ocean along a west to east transect

• Published in: Geophysical Research Letters
• Main Authors: Walter, Sylvia, Bange, Hermann W., Wallace, Douglas W.R.
• Format: Article in Journal/Newspaper
• Language: English
• Published: AGU (American Geophysical Union) 2004
• Subjects: North Atlantic
• Online Access: https://oceanrep.geomar.de/id/eprint/5748/; https://oceanrep.geomar.de/id/eprint/5748/1/Walter_et_al-2004-Geophysical_Research_Letters.pdf; http://www.agu.org/journals/ss/SOLAS1; https://doi.org/10.1029/2004GL019937

Nitrous oxide (N2O) was measured during the first German SOLAS (Surface Ocean – Lower Atmosphere Study) cruise in the tropical North Atlantic Ocean on board R/V Meteor during October/November 2002. About 900 atmospheric and dissolved N2O measurements were performed with a semi-continuous GC-ECD system equipped with a seawater-gas equilibrator. Surface waters along the main transect at 10°N showed no distinct longitudinal gradient. Instead, N2O saturations were highly variable ranging from 97% to 118% (in the Guinea Dome Area, 11°N, 24°W). When approaching the continental shelf of West Africa, N2O surface saturations went up to 113%. N2O saturations in the region of the equatorial upwelling (at 0–1.5°N, 23.5–26°W) were correlated with decreasing sea surface temperatures and showed saturations up to 109%. The overall mean N2O saturation was 104 ± 4% indicating that the tropical North Atlantic Ocean is a net source of atmospheric N2O.