For about half the year, the Strait of Tartary in the Russian Far East is capped with ice. Just weeks before the waters began their seasonal freeze-up in November 2022, the Operational Land Imager-2 (OLI-2) on Landsat 9 acquired one of autumn’s last images of the strait’s colorful, dynamic waters.
The strait is sandwiched between mainland Russia and Sakhalin Island, and it connects the Sea of Japan with the Sea of Okhotsk. The northern part of the strait, also known as the Amur Liman, receives freshwater from the Amur River. The Amur is the world’s tenth-longest river, which flows east along the Chinese-Russian border before turning northeast and emptying into the strait.
Flooding is common along the river from spring through autumn. In the spring, melting snow and thawing soils lead to a surge of meltwater, or freshet. The surge of water carries sediments and organic materials into the strait, coloring its waters brown. A second pulse of water in summer and autumn comes from rainfall that accompanies the monsoon and sweeps more materials into the river and eventually into the strait.
When this image was acquired on October 25, 2022, the flooding season was coming to an end. Still, the mighty Amur River continued to deliver sediment and dissolved organic matter that likely contributed to the colorful waters visible in the image. Already, patches of snow were visible on the land—rebuilding a source of water for next year’s floods.
NASA Earth Observatory image by Lauren Dauphin, using Landsat data from the U.S. Geological Survey. Story by Kathryn Hansen.