Methanol Concentrations and Biological Methanol Consumption in the Northwest Pacific Ocean

Abstract

Methanol is one of the most abundant oxygenated volatile organic compounds in the atmosphere and plays an important role in atmospheric chemistry and ocean ecology (Heikes et al., 2002;Singh et al., 2001;Zhuang et al., 2018). Due to the variability of methanol concentrations and sea-air exchange fluxes between locations, uncertainty remains as to whether the ocean is a source or sink of atmospheric methanol. For example, Beale et al. ( 2013) observed methanol exchange in both directions in the Atlantic Ocean with a net oceanic emission of 12 Tg yr −1 , while Yang et al. ( 2013) reported a global extrapolation of −42 Tg yr −1 based on the atmospheric deposition of methanol over the Atlantic Ocean. In situ methanol production is often observed in oceanic waters (Dixon, Beale, et al., 2013) and phytoplankton could be a key methanol producer (Mincer & Aicher, 2016). However, methanol concentrations are maintained in the nanomolar range due to rapid consumption by marine microorganisms (

Simultaneous determination of seawater trimethylamine and methanol by purge and trap gas chromatography using dual nitrogen-phosphorus detector and flame-ionization detector

“…Although production rates can be higher in coastal waters, rapid consumption of methanol in near-shore waters would maintain methanol concentration at a low level. In the Northwest Pacific Ocean, atmospheric deposition is also a source of methanol and it accounted for 22.7% of microbial methanol consumption in the mixed layer (Zhou et al, 2023). Collectively, the in situ concentrations of trimethylamine and methanol reflected the relative importance of production and consumption processes involved in their cycling in marine environments.…”

“…Arabian Sea (Gibb et al, 1999) 1.6 ± 1.8 Coast, Antarctica (Gibb and Hatton, 2004) 1.4 -6.9 Southern Ocean (Cree et al, 2018) 1.7 -8.3 Dalian coast, China (Wu et al, 2020) Methanol 118.4 ± 48.2 Tropical Atlantic (Williams et al, 2004) 77.9 -325.0 Western Pacific Ocean (Kameyama et al, 2010) 48 -361 Atlantic Ocean (Beale et al, 2013) 15 -62 Atlantic Ocean (Yang et al, 2013) 7 -28 Atlantic Ocean (Yang et al, 2014) 16 -78 Plymouth coast, UK (Beale et al, 2015) 67 ± 35 Southern Ocean (Wohl et al, 2020) < 12 -391 Northwest Pacific Ocean (Zhou et al, 2023) 4 Conclusion…”

“…Similar to trimethylamine, methanol is ubiquitous in marine systems and largely produced by phytoplankton (Yang et al, 2013;Mincer and Aicher, 2016). Methanol is predominately used as a microbial energy source for CO 2 production (Zhou et al, 2023), and was also observed as an important carbon source channeled into biomass in highly productive areas (Dixon et al, 2013b;Zhuang et al, 2018b). Therefore, the metabolism of trimethylamine and methanol constitute an important part of the marine carbon and nitrogen cycles.…”