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Sanriku Fukkō NP, Aomori / Iwate
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At Kitayamazaki, an Environment Ministry ranger photographed a clear view, then—10 minutes later—the lookout wrapped in Yamase cloud. Before it swallows the cliffs, it can spread below like a cloud sea.
Yamase is the cold, damp easterly wind—not the fog itself. In early and midsummer it carries low cloud and mist from the Okhotsk High across the Pacific onto Sanriku’s coast.
In Hachinohe and northern Iwate, Nanbu wheat crackers were valuable stored food where cool summers often made rice scarce. After World War II, bakers made a broth-ready version for senbei-jiru—chewy, not mushy.
Tanesashi Coast supports more than 650 coastal and alpine plant species. Its unusual ecosystem reflects Yamase, sea fog and little winter snow, plus horse grazing that maintained the natural turf until about 1965.
A Sanriku study found the fog’s direction changes its effect: northeastern fog was usually colder but reduced sunlight less; southeastern fog was often warmer, yet its overlying low cloud cut sunlight sharply.
In the 1980 Yamase-type cold summer, Sanriku’s rice crop index fell to 10 or below, while the Kitakami Basin reached 60; 100 means normal. One weather pattern split harvests dramatically across the region.
Miyazawa Kenji’s famous poem “Ame ni mo Makezu” mentions “cold summers”; Japan’s Meteorological Agency explicitly links the line to Yamase-driven cold. The misty coast left its mark on literature.
Between Karumai and Taneichi, researchers mapped Yamase fog entering inland along valleys, then often disappearing as it crossed mountains. Here, ridgelines can mark the fog’s abrupt inland boundary.
In June 2025, scientists investigating unusually warm Sanriku waters used 2 ships and an Ōtsuchi shore station for 61 hours of hourly balloon readings. They caught heavy fog over warm water and sudden low-level wind shifts.
