Program and Agenda

Abstract

EVALUATION OF USING UNFILTERED SEAWATER FOR UNDERWAY MEASUREMENT OF DIMETHYL SULFIDE IN THE OCEAN BY ONLINE MASS SPECTROMETRY

New, highly time-resolved techniques for measuring dimethyl sulfide (DMS) concentrations in seawater provide the opportunity to greatly increase the size of the DMS concentration database. However, lack of community-level quality control raises concerns about the quality of data obtained by these new techniques. One of the concerns is the use of a continuous flow of unfiltered seawater as a sample. Phytoplankton in unfiltered seawater might produce DMS in the sample, resulting in inaccurate DMS concentrations. Here, in our equilibrator inlet–proton transfer reaction–mass spectrometry technique, we conducted laboratory experiments in a closed system at equilibrium to investigate the possible artifact from using unfiltered seawater and the magnitude of its effects. DMS concentration increased when unfiltered seawater was bubbled with N2 but not when it was bubbled with air, and the increase occurred just after dissolved O2 was depleted in the seawater in the equilibrator. These results indicate that O2 depletion artificially increased DMS concentrations in unfiltered seawater. This artifact could be avoided by maintaining aerobic conditions in the equilibrator.

ePoster:

Authors

Omori, Y., National Institute for Environmental Studies, Japan, omori.yuko@nies.go.jp

Tanimoto, H., National Institute for Environmental Studies, Japan, tanimoto@nies.go.jp

Inomata, S., National Institute for Environmental Studies, Japan, ino@nies.go.jp

Kameyama, S., Hokkaido University, Japan, skameyama@ees.hokudai.ac.jp

Suzuki, K., Hokkaido University, Japan, kojis@ees.hokudai.ac.jp

Details

Poster presentation

Session #:043
Date: 2/24/2014
Time: 16:00 - 18:00
Location: Poster/Exhibit Hall

Presentation is given by student: No

PosterID: 27