In situ quality assessment of a novel underwater pCO2 sensor based on membrane equilibration and NDIR spectrometry

Fietzek, Peer, Fiedler, Björn, Steinhoff, Tobias and Körtzinger, Arne (2014) In situ quality assessment of a novel underwater pCO2 sensor based on membrane equilibration and NDIR spectrometry Journal of Atmospheric and Oceanic Technology, 31 (1). pp. 181-196. DOI 10.1175/JTECH-D-13-00083.1.

[img]
Preview
Text
jtech-d-13-00083.1.pdf - Accepted Version

Download (1584Kb) | Preview
[img]
Preview
Text (Correction)
jtech-d-14-00092.1.pdf - Published Version

Download (28Kb) | Preview

Supplementary data:

Abstract

We present a detailed quality assessment of a novel underwater sensor for the measurement of CO2 partial pressure (pCO2) based on surface water field deployments carried out between 2008 and 2011. The commercially available sensor, which is based on membrane equilibration and NDIR spectrometry is small and can be integrated into mobile platforms. It is calibrated in water against a proven flow-through pCO2 instrument within a custom-built calibration setup. The aspect of highest concern with respect to achievable data quality of the sensor is the compensation for signal drift inevitably connected to absorption measurements. We use three means to correct for drift effects: (i) a filter correlation or dual-beam setup, (ii) regular zero gas measurements realized automatically within the sensor and (iii) a zero-based transformation of two sensor calibrations flanking the time of sensor deployment.
Three sensors were tested against an underway pCO2 system during two major research cruises providing an in situ temperature range from 7.4 to 30.1°C and pCO2 values between 289 and 445 μatm. The average difference between sensor and reference pCO2 was found to be -0.6 ± 3 μatm with a RMSE of 3.7 μatm.

Document Type: Article
Additional Information: WOS:000329544600007; Correction: JOURNAL OF ATMOSPHERIC AND OCEANIC TECHNOLOGY, 31 (7):1673-1674; 10.1175/JTECH-D-14-00092.1 JUL 2014 WOS:000339102200017
Research affiliation: OceanRep > GEOMAR > FB2 Marine Biogeochemistry > FB2-CH Chemical Oceanography
OceanRep > The Future Ocean - Cluster of Excellence > FO-R10
OceanRep > The Future Ocean - Cluster of Excellence
Kiel University
Refereed: Yes
DOI etc.: 10.1175/JTECH-D-13-00083.1
ISSN: 0739-0572
Projects: OCEANET, SOPRAN, Future Ocean
Expeditions/Models:
Date Deposited: 08 Oct 2013 09:01
Last Modified: 10 Apr 2017 11:03
URI: http://eprints.uni-kiel.de/id/eprint/22071

Actions (login required)

View Item View Item

Document Downloads

More statistics for this item...