Deep-Sea Research II 52 (2005) 1133–1155 Measurement and simulation of viscous dissipation in the wave affected surface layer Adolf Stips a,Ã , Hans Burchard b , Karsten Bolding c , Hartmut Prandke d , Andre´ Simon e , Alfred Wu¨est f a CEC Joint Research Centre, Institute for Environment and Sustainability, I-21020 Ispra(VA), Italy b Institute for Baltic Sea Research, Universita¨t Rostock, Seestrasse 15, D-18119 Rostock, Germany c Bolding & Burchard Hydrodynamics GbR, Strandgyden 25, DK 5466 Asperup, Denmark d ISW Wassermesstechnik Dr. Hartmut Prandke, Lenzer Street 5, D-17213 Petersdorf, Germany e EAWAG, CH-8600 Du¨bendorf, Switzerland f Applied Aquatic Ecology, EAWAG, CH-6047 Kastanienbaum, Switzerland Accepted 15 January 2005 Abstract Inthisstudywecompareturbulenceparametersfromfieldobservationsandmodelsimulationsspecificallyunderthe influence of weak to moderate wind forcing and breaking short waves. The experiment was performed during 12 days under very weak stratification at a fetch-limited lake in Switzerland. The near surface observations were obtained by using a quasi-free rising profiler which measured small scale shear and temperature fluctuations. We used a two- equation k– turbulence model with an algebraic second-moment closure scheme. The one-dimensional numerical model was extended to consider breaking waves by a shear-dependent parameterisation. The agreement of observed and simulated turbulence quantities is very promising. Especially well simulated is the enhanced turbulence level in the wave-affected-surface-layer (WASL) of a few dm thickness. The logarithmic slope of the turbulent dissipation rate in this WASL was found to vary between 2:1and 1:7.BelowtheWASLtheclassic law-of-the-wall was well reproduced by the data and the model. r 2005 Elsevier Ltd. All rights reserved. 1. Introduction The surface boundary layer (SBL) of natural waters is a corner stone of earth sciences. Under- standing and adequate parameterisation of heat, gas and momentum exchange with the atmo- sphere—especially under breaking waves—is fun- damental for the physical and biogeochemical processes in oceans, lakes and reservoirs. The early measurements in lakes (Thorpe, 1977; Dillon et al., 1981) and oceans (Lombardo and Gregg, 1989) revealed regularly logarithmic velo- city profiles with rates of dissipation  of turbulent ARTICLE IN PRESS www.elsevier.com/locate/dsr2 0967-0645/$-see front matter r 2005 Elsevier Ltd. All rights reserved. doi:10.1016/j.dsr2.2005.01.012 Ã Corresponding author. E-mail address: adolf.stips@jrc.it (Adolf Stips).