Located on a similar geographical latitude as Portland (Oregon) and Venice (Italy), the Sea of Okhotsk coast of Hokkaido is the northern hemisphere's southernmost region to see drifting sea ice. The sea ice typically reaches the coast around Abashiri in mid to late January and disappears again by late March to mid April. The best time to view it is usually around the second half of February.
While drift ice (流氷, Ryūhyō) can be observed along the entire Sea of Okhotsk coast from Wakkanai to the Shiretoko Peninsula, it gets thickest around Abashiri. Due to global warming, the amount and thickness of the drift ice has decreased quite considerably since the late 1980s.
One of the best and easiest ways to see the drift ice is from the Aurora Sightseeing Boats, which depart from Abashiri Port. Because drift ice is not always visible from the coast, the boats travel out into the Sea of Okhotsk to where ice is more likely to be found. The boat rides take about an hour and run several times a day from late January to the end of March. Online ticket reservations can be made through Japanican.
Under good conditions, the drift ice can also be observed from the coast. A popular way to do so is from the trains between Abashiri and Shiretoko-Shari Stations. The nostalgic Ryuhyo Norokko train has panorama windows and operates along the coast during the drift ice season. The science behind the sea ice, a wide screen introductory movie and some of the small animals living below the ice, are introduced in the Okhotsk Ryuhyo Museum on Mount Tento in Abashiri.