Short answers, pulled from the story.
The Sea of Okhotsk is a marginal sea of the northwestern Pacific Ocean. It is bordered by Russia's Kamchatka Peninsula to the east, the Kuril Islands to the southeast, Japan's island of Hokkaido to the south, and the island of Sakhalin and eastern Siberia to the west and north.
The Amur River discharges large volumes of freshwater into the Sea of Okhotsk, lowering the salinity of the upper water layer. Lower salinity raises the freezing point of the surface, allowing ice to form more readily when cold Siberian air sweeps over the sea in winter.
The Peanut Hole is an area of open ocean at the center of the Sea of Okhotsk, roughly 55 kilometers wide and 480 kilometers long, that lies outside Russia's exclusive economic zone despite being surrounded by it. In 1992, foreign fleets caught perhaps as much as one million metric tons of pollock there. A United Nations ruling in March 2014 recognized it as part of Russia's continental shelf, ending open-access fishing.
Russian explorers Vassili Poyarkov in 1639 and Ivan Moskvitin in 1645 were the first Europeans to visit the Sea of Okhotsk. Dutch captain Maarten Gerritsz Vries followed in 1643, charting parts of the Sakhalin coast and Kuril Islands from the Breskens, though he did not recognize that Sakhalin or Hokkaido were islands.
On the 18th of December 2011, the Russian oil drilling rig Kolskaya capsized and sank in a storm approximately 124 kilometers from Sakhalin island while being towed from Kamchatka. Its pumps reportedly failed, causing it to take on water. Of the 67 people on board, 14 were rescued by the Magadan and the tugboat Naftogaz-55.
The salmon catch on Japan's northern coast has fallen by 70 percent over the past 15 years as warming drives fish populations northward. In contrast, Russian chum salmon catches have quadrupled over the same period. The Sea of Okhotsk has warmed by as much as 3 degrees Celsius in some areas since preindustrial times, three times faster than the global mean.