Nitrous oxide and hydroxylamine measurements in the Southwest Indian Ocean.

Ma, Xiao, Bange, Hermann W. , Eirund, Gesa K. and Arévalo-Martínez, Damian L. (2020) Nitrous oxide and hydroxylamine measurements in the Southwest Indian Ocean. Journal of Marine Systems, 209 . Art.Nr. 103062. DOI 10.1016/j.jmarsys.2018.03.003.

[img] Text
1-s2.0-S0924796317301392-main.pdf - Published Version
Restricted to Registered users only

Download (3039Kb) | Contact
[img] Text
1-s2.0-S0924796317301392-mmc1.docx - Supplemental Material
Restricted to Registered users only

Download (1184Kb) | Contact

Supplementary data:

Abstract

Highlights:
• Enhanced surface N2O saturations were found between 5°S and 10°S in the SWIO.
• The SWIO was a rather weak source of N2O to the atmosphere.
• A distinct N2O maximum was found at about 1000 m.
• The distributions of NH2OH in the water column were highly variable.
• Nitrification was the major formation pathway of N2O in the SWIO.

The southwestern basin of the Indian Ocean (SWIO) remains a rather under-sampled region with regard to nitrogen-cycle processes. Here we present the results of extensive nitrous oxide (N2O) measurements as well as the first reported open ocean measurements of hydroxylamine (NH2OH). Enhanced N2O sea-to-air fluxes were found in the zonal band between 5°S and 10°S as a result of wind-driven upwelling, and N2O depth profiles showed supersaturation throughout the water column with a distinct maximum at about 1000 m. Excess N2O (ΔN2O) was found to be positively correlated with apparent oxygen utilization (AOU) and nitrate. Although the water column distribution of NH2OH was highly variable, combined analysis with N2O and nutrient data allows us to argue for nitrification as the major formation pathway of N2O in the SWIO.

Document Type: Article
Funder compliance: info:eu-repo/grantAgreement/EC/FP7/284274
Keywords: Nitrous oxide; Hydroxylamine; Southwest Indian Ocean; Open ocean upwelling; Nitrification; Hydroxylamine; Atmospheric gases; Air-water interface; Hydrography
Research affiliation: OceanRep > The Future Ocean - Cluster of Excellence > FO-R07
OceanRep > The Future Ocean - Cluster of Excellence
OceanRep > GEOMAR > FB2 Marine Biogeochemistry > FB2-CH Chemical Oceanography
OceanRep > GEOMAR > Applied R&D > Energy and CO₂ Sequestration Projects
Refereed: Yes
Open Access Journal?: No
DOI etc.: 10.1016/j.jmarsys.2018.03.003
ISSN: 0924-7963
Related URLs:
Projects: Future Ocean, SOPRAN, InGOS
Expeditions/Models/Experiments:
Date Deposited: 09 May 2018 11:22
Last Modified: 09 Jun 2020 03:49
URI: http://oceanrep.geomar.de/id/eprint/42918

Actions (login required)

View Item View Item

Document Downloads

More statistics for this item...