  Based on an eddy-permitting ocean circulation model, the eddy kinetic energy
(EKE) sources are studied in the Sea of Okhotsk. An analysis of the spatial
distribution of the EKE showed that intense mesoscale variability occurs along
the western boundary of the Sea of Okhotsk, where the East-Sakhalin Current
extends. It was found a pronounced seasonally varying EKE with its maximal
magnitudes in winter, and its minimal magnitudes in summer.
  An analysis of the EKE sources and the energy conversions showed that
time-varying (turbulent) wind stress is a main contribution to mesoscale
variability along the western boundary of the Sea of Okhotsk. The contribution
of baroclinic instability to the generation of mesoscale variability
predominates over that of barotropic instability along the western boundary of
the Sea of Okhotsk.
  To demonstrate the mechanism of baroclinic instability, the circulation was
considered along the western boundary of the Sea of Okhotsk from January to
April 2005. An analysis of hydrological conditions showed outcropping
isopycnals and being strong vertical shear of the along-shore velocity from
January to May 2005. In April, mesoscale eddies are observed along the western
boundary of the Sea of Okhotsk. It was established that seasonal variability of
turbulent wind stress and the baroclinic instability of the East-Sakhalin
Current are major reasons of mesoscale variability along the western boundary
of the Sea of Okhotsk.
