DMS cycle in the marine ocean-atmosphere system – a global model study

Abstract

Abstract.A global coupled ocean-atmosphere modeling system is established to study the production of dimethylsulfide (DMS) in the ocean, the DMS flux to the atmosphere, and the resulting sulfur concentrations in the atmosphere. The DMS production and consumption processes in the ocean are simulated in the marine biogeochemistry model HAMOCC5, embedded in a ocean general circulation model (MPI-OM). The atmospheric model ECHAM5 is extended by the microphysical aerosol model HAM, treating the sulfur chemistry in the atmosphere and the evolution of the microphysically interacting internally-and externally mixed aerosol populations.We simulate a global annual mean DMS sea surface concentration of 1.8 nmol l −1 , a DMS emission of 28 Tg(S) yr −1 , a DMS burden in the atmosphere of 0.077 Tg(S), and a DMS lifetime of 1.0 days. To quantify the role of DMS in the atmospheric sulfur cycle we simulate the relative contribution of DMS-derived SO 2 and SO

Estimation of bubble-mediated air–sea gas exchange from concurrent DMS and CO<sub>2</sub> transfer velocities at intermediate–high wind speeds

“…Seawater DMS levels were much higher than atmospheric levels, reflecting the biogenic sources in seawater and the relatively short atmospheric lifetime (∼ 1 day; Kloster et al, 2006). The largest air-sea DMS concentration differences ( DMS) of 6-12 ppb were observed during DOY 185-190 (Fig.…”

Amplification of global warming through pH dependence of DMS production simulated with a fully coupled Earth system model

“…The parameterisation of the DMS cycle in HAMOCC has been implemented and evaluated by Six and Maier-Reimer (2006) and Kloster et al (2006). Processes included are DMS production and losses by bacterial consumption, photolysis, and sea-air DMS gas exchange.…”

“…For this study, we use the same set of tunable parameters as Kloster et al (2006) and Six et al (2013), except for the scaling factor for bacterial consumption, which is reduced by half to better reproduce the observed fluxes. We refer the reader to Kloster et al (2006) and Six et al (2013) for a detailed description of the DMS parameterisation used here.…”

Dimethylsulfoniopropionate (DMSP) and dimethyl sulfide (DMS) cycling across contrasting biological hotspots of the New Zealand subtropical front

“…Nearly encircling the entire globe in a meridional band between 35 and 45 • S, the subtropical convergence, or hereafter termed the subtropical front (STF), spreads for the most part across remote regions of the planet where anthropogenic sources of atmospheric compounds exert subordinate influence on local aerosol patterns compared to natural sources. Modellingbased evidence suggests that cloud condensation nuclei seasonality is driven mainly by DMS oxidation in this part of the ocean (Gondwe et al, 2003;Kloster et al, 2006;Vallina et al, 2006). Episodic phytoplankton bloom events in the STF occur mostly in austral spring-summer, with varying lifetimes of 8 to 60 days (Llido et al, 2005).…”