Internal wave depiction in Lake Maninjau from high frequency temperature data

Abstract

Abstract Water column of Lake Maninjau has a thermal stratification which sensitive to varying conditions of weather variables, especially to wind forcing. When water column stratified, wind forcing will initiate an internal wave generation in water column. Internal wave has a significant role in physical, chemical and biological processes in lakes. The aim of this study was to illustrate the internal wave in Lake Maninjau. Temperature data and wind speeds were collected from environmental monitoring and warnings system (e-most) device and weather stations of UPT LATPD Maninjau, respectively. The observation periods were conducted for 10 days (April, 1-10 2017). Strong stratification significantly appears in the beginning of observation period. Internal wave drawn from the temperature oscillations at a depth of 1, 9, 14 and 25 m with a vertical V2H1 mode. Our analysis showed that internal waves resonate with wind speed at the frequency of 6.9 × 10−3 cyc/minutes (23.9-h period).