Lagrangian Analysis of Pacific Waters in the Sea of Okhotsk Based on Satellite Data in Application to the Walleye Pollock Fishery.

The trajectories of 114 000 passive particles regularly distributed on a grid in the Sea of Okhotsk are calculated for each day of the interval from January 31, 1997 to March 10, 2021, based on satellite altimetry data on geostrophic current speeds. All particles coming to the Sea of Okhotsk from the Pacific Ocean are identified and the age of the Pacific-origin waters and the area where these waters enter the sea are determined. Using daily vessel-position data in the walleye pollock fishery from 1997 to 2021, Lagrangian maps of the origin and age of the Pacific waters over the same period, and statistical analysis, it is shown that the Walleye pollock fishing grounds are more often in the Pacific waters which passed through the northern Kuril Straits not more than 100 days before the catch dates than in the waters which entered the sea to the south or have been in the sea for more than 100 days. Analysis of satellite imagery of sea surface temperatures leads to the conclusion that the reasons for the aggregation of walleye pollock catch locations in intrusions and Lagrangian fronts of Pacific waters are their warmer temperatures and higher concentrations of feed. [ABSTRACT FROM AUTHOR]