赤あか潮しお

noun

red tide

A harmful algal bloom that discolors seawater, often causing marine life die-offs. Common in news and environmental contexts.

• 今年ことしの夏なつ、沿えん岸がんで赤あか潮しおが発はっ生せいした。

  This summer, a red tide occurred along the coast.

• 赤あか潮しおの影えい響きょうで多おおくの魚さかなが死しんだ。

  Many fish died due to the red tide.