Abstract <p>The intermediate water ventilation in the subpolar Pacific is governed by the water exchange with the Sea of Okhotsk. The mechanism of this exchange has not yet been revealed. The processes that lead to changes in the water exchange through the Kuril Islands straits also have not yet been identified. It was previously suggested that the exchange occurs through deep straits along the Kuril Islands (the Boussole and Kruzenshtern straits). Based on direct observations of Argo and Argos buoys, the transport of water from the Sea of Okhotsk via the straits in the Middle Kuril Islands is shown. Namely, the position of the large anticyclonic eddy near the Boussole Strait can determine the exchange of the water from the Sea of Okhotsk with the ocean water through the Nadezhda Strait. A significant cooling of the Oyashio and Kamchatka Current eddies in extremely cold years is also shown. A particularly strong cooling and desalination of the Oyashio intermediate water occurred in the extremely cold year. At the same time, a flow of low-salinity water from the Sea of Okhotsk through the Nadezhda Strait was observed. In the extremely cold year, the record deepening of the Oyashio intermediate water occurred. The noticeable warming in subsequent years was associated with a flow of warm and saline intermediate water from the Kuroshio frontal zone. These observations demonstrate different sources of intermediate water in the Oyashio eddies depending on winter conditions in the region.</p>