Estimate of eddy energy generation/dissipation rate in the world ocean from altimetry data

摘要

Assuming eddy kinetic energy is equally partitioned between the barotropic mode and the first baroclinic mode and using the weekly TOPEX/ERS merged data for the period of 1993~2007, the mean eddy kinetic energy and eddy available gravitational potential energy in the world oceans are estimated at 0.157 and 0.224 EJ; the annual mean generation/dissipation rate of eddy kinetic energy and available gravitational potential energy in the world oceans is estimated at 0.203 TW. Scaling and data analysis indicate that eddy available gravitational potential energy and its generation/dissipation rate are larger than those of eddy kinetic energy. High rate of eddy energy generation/dissipation is primarily concentrated in eddy-rich regions, such as the Antarctic Circumpolar Current and the western boundary current extensions. Outside of these regimes of intense current, the energy generation/dissipation rate is two to four orders of magnitude lower than the peak values; however, along the eastern boundaries and in the region where complicated topography and current interact the eddy energy generation/dissipation rate is several times larger than those in background.