A miniature Marine Aerosol Reference Tank (miniMART) as a compact breaking wave analogue

Abstract

Abstract. In order to understand the processes governing the production of marine aerosols, repeatable, controlled methods for their generation are required. A new system, the miniature Marine Aerosol Reference Tank (miniMART), has been designed after the success of the original MART system, to approximate a small oceanic spilling breaker by producing an evolving bubble plume and surface foam patch. The smaller tank utilizes an intermittently plunging jet of water produced by a rotating water wheel, into an approximately 6 L reservoir to simulate bubble plume and foam formation and generate aerosols. This system produces bubble plumes characteristic of small whitecaps without the large external pump inherent in the original MART design. Without the pump it is possible to easily culture delicate planktonic and microbial communities in the bulk water during experiments while continuously producing aerosols for study. However, due to the reduced volume and smaller plunging jet, the absolute numbers of particles generated are approximately an order of magnitude less than in the original MART design.

A Systematic Analysis of the Salinity Effect on Air Bubbles Evolution: Laboratory Experiments in a Breaking Wave Analog

“…Bubble film radii at the water surface shift to smaller sizes as the surface foam evolves indicating that the contribution of film and jet drops varies during foam decay. Our results confirm the concerns put forward by many previous researchers (Collins et al, 2014;Salter et al, 2014;Stokes et al, 2016;Wang et al, 2017), who argued that continuous air entrainment could lead to a biased aerosols emission from the surface foam. Accordingly, we suggest that it is important to allow enough time for the bubble plumes and surface foams to evolve following active air entrainment in future experimental studies dealing with aerosolization from aquatic environments.…”

“…Due to the difficulty of reproducing air entrainment from breaking waves in small-scale laboratory systems, researchers have used different experimental setups to generate subsurface bubbles including porous glass tubes (Mårtensson et al, 2003;Scott, 1975), overturning buckets (Carey et al, 1993;Haines & Johnson, 1995), continuous jets (May et al, 2016;Salter et al, 2014), intermittent water sheets (Stokes et al, 2013(Stokes et al, , 2016, and wave channels (Deane & Stokes, 2002;Li et al, 2017;Loewen et al, 1996). The validity of such setups to faithfully reproduce air-water interactions from breaking waves depends on their ability to replicate the in situ bubbles and aerosols size distributions (Fuentes et al, 2010;Stokes et al, 2013).…”

Temperature and Composition Dependence of Sea Spray Aerosol Production

“…The marine aerosol reference tank (MART) and miniature MART (miniMART) are recently developed methods for particle generation from seawater. They yield bubble size distributions very similar to those observed for waves produced in wave channels Stokes et al, 2016) suggesting that they are more representative of actual ocean behavior compared to plunging jets or sintered glass filters. Similarly, particle size distributions from these wave-breaking analogs are similar to those produced from breaking waves in a wave channel Stokes et al, 2016).…”

“…They yield bubble size distributions very similar to those observed for waves produced in wave channels Stokes et al, 2016) suggesting that they are more representative of actual ocean behavior compared to plunging jets or sintered glass filters. Similarly, particle size distributions from these wave-breaking analogs are similar to those produced from breaking waves in a wave channel Stokes et al, 2016). This contrasts with sintered glass filters, which tend to yield narrower distributions with smaller mean diameters compared to waves in wave channels .…”

“…Both a MART and miniMART were used to separately generate SSA particles, with detailed descriptions of both available in Stokes et al (2016Stokes et al ( , 2013 and further details about their operation for these experiments in the supporting information. The MART generated SSA particles using an intermittent plunging sheet of water.…”