On 23 January one of NASA’s satellites captured a stunning image of cloud streets over the Bering Sea. The frozen tundra of Russia is visible on the upper left-hand side of the photo, while Alaska can be seen on the right. Sea ice extends far from both land masses into the ocean.
The thin white lines of clouds that seem to cascade off and away from the sea of ice are known as “cloud streets” because of the way they develop parallel to one another. They are formed by convection rolls of rising warm air and sinking cool air that give the clouds their cylindrical shape, leaving the sky in between them clear. This clear-cloudy pattern then gets blown in the same direction as the wind, giving the impression of parallel rows of streets.
The photo was taken by an instrument known as the Moderate Resolution Imaging Spectroradiometer (MODIS), which resides on NASA’s Aqua satellite. This isn’t the first time that MODIS has snapped such a shot. It has caught glimpses of cloud streets in other parts of the world, too. For instance, the image below was captured by MODIS over the Black Sea just a couple weeks before the Bering Sea photo, on 8 January 2015.