Onboard measurement system of atmospheric carbon monoxide in the Pacific by voluntary observing ships

Abstract

Abstract. Long-term monitoring of carbon monoxide (CO) mixing ratios in the atmosphere over the Pacific Ocean is being carried out on commercial cargo vessels participating in the National Institute for Environmental Studies Voluntary Observing Ships program. The program provides a regular platform for measurement of atmospheric CO along four cruise routes: from Japan to Oceania, the United States, Canada, and Southeast Asia. Flask samples are collected during every cruise for subsequent analysis in the laboratory, and in 2005, continuous shipboard CO measurements were initiated on three of the routes. Here, we describe the system we developed for onboard measurement of CO mixing ratios with a commercially available gas filter correlation CO analyzer. The fully automated system measures CO in ambient air, and the detector sensitivity and background signals are calibrated by referencing the measurements to a COin-air standard gas (∼1 ppmv) and to CO-free air scrubbed with a catalyst, respectively. We examined the artificial production of CO in the high-pressure working gas standards during storage by referencing the measurements to CO standard gases maintained as our primary scale before and after use on the ships. The onboard performance of the continuous CO measurement system was evaluated by comparing its data with data from laboratory analyses of flask samples using gas chromatography with a reduction gas detector. The reasonably good consistency between the two independent measurement methods demonstrated the good performance of both methods over the course of 3-5 years. The continuous measurement system was more useful than the flask sampling method for regionally polluted air masses, which were often encountered on Southeast Asian cruises.

Metrological problems of gas analyzers based on wavelength-scanned cavity ring-down spectroscopy

“…Thus, the results of measurements of isotope ratio δ 13 C in the gas mixtures of CO 2 with nitrogen, air, and argon differ by factor k ± Δk. Table 5 shows that the results of this work are in agreement with the results of [9]. The measured difference of parameters δ 13 C for CO 2 in air and nitrogen is in agreement with the theoretical difference.…”

“…Table 5 presents the experimental results and compares the results of this work and [9]. Thus, the results of measurements of isotope ratio δ 13 C in the gas mixtures of CO 2 with nitrogen, air, and argon differ by factor k ± Δk.…”

“…The experimental results are in agreement for carbon dioxide in air and argon. Note that the experimental and theoretical differences substantially differ from each other in [9]. This circumstance may be due to the incorrect model of the spectral band shape.…”

Emissions of methane from offshore oil and gas platforms in Southeast Asia

“…The sampled air was dehumidified by passing it through a sample-drying unit consisting of an electric cooler kept at +1°C and a Nafion Perma Pure dryer (Perma Pure LLC, Toms River, NJ, USA). The design and performance of the unit was very similar to that used for the CO measurements13. The sampled air was dried to less than ~0.3% water (as measured by the WS-CRDS) before the mole fractions of CO 2 and CH 4 were determined based on the water vapor content according to an instrument-specific water vapor collection function33.…”

Analysis of Southeast Asian pollution episode during June 2013 using satellite remote sensing datasets

“…Close to the vegetation fires at Palangkaraya on Kalimantan and Jambi on Sumatra up to 4000 mg/m 3 total particulate matter was measured, exceeding the Indonesian national ambient air quality standard by a factor of 15 (Heil and Goldammer, 2001). In Indonesia, peatland fires are common (Nara et al, 2011;Hyer et al, 2013). Peatlands occupy 170,000e270,000 km 2 (Heil and Goldammer, 2001) and it is estimated that they store 57,367Gt of carbon (Page et al, 2011).…”