Internal Waves and Mixing in the Marginal Ice Zone near the Yermak Plateau

摘要: Observations were made of oceanic currents, hydrography, and microstructure in the southern Yermak Plateau summer 2007. The location is marginal ice zone at Arctic Front northwest Svalbard, where West Spitsbergen Current (WSC) carries warm Atlantic Water into Ocean. Time series approximately 1-day duration from five stations (upper 520 m) an 8-day a mooring are analyzed to describe characteristics internal waves turbulent mixing. spectral composition internal-wave field over 0.1‐0.3 times midlatitude levels compares with most energetic central Arctic. Dissipation rate eddy diffusivity below pycnocline increase noise level on cold side front by one order magnitude side, 100-m-thick layers average diffusivities 5 3 10 25 m 2 s 21 lead heat loss 2‐4 W 22 . upper 150 well above all stations, but strong stratification prohibits mixing across pycnocline. Close shelf, core Svalbard branch WSC, increases another factor 3‐6. Here, nearbottom removes 15 layer. Internal-wave activity show variability related topography hydrography; thus, path WSC will affect cooling freshening inflow. When generalized Ocean, diapycnal away abyssal plains can be significant for budget. Around Plateau, it sufficient influence anomaly pulses entering Ocean; however, alone unlikely regional WSC.