The Heidelberg Aeolotron is a large annular wind-wave facility to investigate the mechanisms of air-water gas transfer. Several measurement techniques can be used simultaneously to observe the dynamics of the mass transfer across the aqueous viscous boundary layer. A high speed camera captures the 2-D extend of the slope of the water surface with more than 1500 frames per second and a spatial resolution of 0.22 mm (Kiefhaber et al., 2014). Additionally, a Boundary Layer Imaging (BLI) method by Krauter et al. (2014) images the thickness of a controllable fraction of the mass boundary layer with a horizontal resolution of 0.156 mm. Thus, the influence of Langmuir circulations and micro-scale breaking on the air-water gas transfer can be investigated. Besides these two imaging techniques, a thermographic setup determines the heat transfer at the water surface. We present first results in the wind-driven small-scale mechanisms and their influence on the air-water gas

Keywords: Experimental techniques