@conference {hering1995c,
	title = {Flow- and wave-fields associated with micro-scale wave breaking as measured simultaneously by particle tracking and wave slope visualization},
	booktitle = {IAPSO Proceedings, XXI General Assembly, Honolulu, Hawai, August 1995, PS-10 Spatial Structure of Short Ocean Waves},
	number = {19},
	year = {1995},
	pages = {385},
	abstract = {Longuet-Higgins predicted the development of a capillary roller at the crest of a short gravity wave, being the consequence of the existence of parasitic capillaries, (Capillary rollers and bores, J. Fluid Mech, Jan. 1992). According to the theory any free surface, at which the tangential stress vanishes, a surface vorticity is produced. The mean vorticity at the edge of the Stokes layer is of the order of 2(ak) f, ak being the slope and f the radian frequency of the wave. Hence capillary waves, with a high value of a are accompanied by particular large vorticity feeding the vortex roler at the crest of a short gravity wave. This phenomenon has been investigated at the circular facility of the Institute for Environmental Physics. At the same location, simultaneous time series of wave slope images and the Lagrangian flow field were obtained using an integrated optical set-up, including particle-tracking and wave-slope instruments. The particle tracking measurement yields drift- and bulk-velocities, Reynold stresses and the vorticity distribution beneath the wave, while the imaging wave slope gauges gives the 2D-slope and the height of the waves. First results from the measurement campaign of early 1995 will be presented.},
	author = {Frank Hering and G{\"u}nther Balschbach and M. Menzel and Dietmar Wierzimok and Bernd J{\"a}hne}
}
@conference {balschbach1995,
	title = {A new instrument to measure steep wind-waves},
	booktitle = {IAPSO Proceedings, XXI General Assembly, Honolulu, Hawai, August 1995, PS-10 Spatial Structure of Short Ocean Waves},
	number = {19},
	year = {1995},
	pages = {387},
	abstract = {Current instruments to measure the spatial structure of short waves are limited to quite low slopes. Capillary waves, however, may show slopes well above one (45 degrees inclination). A new instrument has been designed to measure the spatial structure of steep capillary waves. It was designed to specifically address a number of basic questions: Is the limiting form for Crapper capillary waves ever reached? Can a bubble be trapped by such a wave? Do solitary capillary/gravity waves - as recently postulated by Longuet-Higgins - exist in wind/wave fields? The instrument uses the basic design as used in previous instruments of our research group but includes two important enhancements. By the use of a telecentric illumination and camera lens, the influence of wave height on the slope measurement is eliminated. Colored light is used to encode both slope components simultaneously and to correct for uneven intensity distribution in the light source and intensity losses by reflection at the water surface. This contribution describes the setup of the instrument and its calibration in detail. First results from the circular wind/wave facility at Heidelberg University are reported in a separate paper.},
	author = {G{\"u}nther Balschbach and M. Menzel and Bernd J{\"a}hne}
}
