Noble gases measured on water bottle samples during Maria S. Merian cruise MSM18/2


During the cruise MSM18/2, 307 helium samples in copper tubes were taken, mainly from the mixed layer and the upper thermocline. These samples will be analysed with respect to helium isotopes (helium-3, helium-4) and neon at the high resolution mass spectrometer at the institute for environmental physics, university of Bremen. The helium isotope data are measured in the framework of the project SOPRAN to infer upwelling velocities. In addition to the traditional copper tube sample technique, a new method for collecting helium/neon samples has been tested during the cruise. Therefore, water samples have been filled into previously evacuated glass ampules. These ampoules can be directly connected to the inlet unit of the mass spectrometer, thus avoiding the additional extraction step which is necessary for the samples fileld in copper tubes. 216 water and 31 blank samples have been taken by this new method at the same stations and depths as the samples in copper tubes. During this first field-test the handling on board and the sampling itself were improved. The comparison of the measured samples from the copper tubes and the glass ampoules from the same Niskin bottle shows good agreement for the helium-3/helium-4 ratio and the neon concentration between both sampling methods. The absolute helium-4 concentration from the glass ampoules was biased low compared to the samples from the copper tubes by about 1%. Thus the helium-4 glass ampoule data were enhanced by 1% before encluding them into the final data set.See "Further details:" for information on measurement technique.

Related Identifier IsDocumentedBy
Metadata Access
Creator Steinfeldt, Reiner ORCID logo; Rhein, Monika ORCID logo
Publisher PANGAEA
Contributor Institut für Umweltphysik, Universität Bremen
Publication Year 2015
Funding Reference German Research Foundation Crossref Funder ID 27542298 Climate - Biogeochemistry Interactions in the Tropical Ocean
Rights Creative Commons Attribution 3.0 Unported;
OpenAccess true
Resource Type Dataset
Format text/tab-separated-values
Size 882 data points
Discipline Biogeochemistry; Biospheric Sciences; Geosciences; Natural Sciences
Spatial Coverage (-23.000W, -5.000S, -9.883E, 5.000N)
Temporal Coverage Begin 2011-05-16T14:20:00Z
Temporal Coverage End 2011-06-13T11:20:00Z