Regardless of the quantity of winter ice cowl, the waters off of the Alaskan coast often come alive every spring with blooms of phytoplankton. These blooms can kind putting patterns of blue and inexperienced seawater, equivalent to these seen in this picture of the Chukchi Sea acquired on June 18, 2018, by the Operational Land Imager (OLI) on Landsat 8.
Blooms are a standard prevalence this time of yr. However the regularity of the blooms and their easy magnificence belie the complexity of this ecosystem.
Two major water plenty circulation from the Bering Strait and enter the southern Chukchi. One kind, generally known as “Bering Sea Water,” is cool, salty, and wealthy in vitamins. This water fuels most of the phytoplankton progress, primarily diatoms, that are doubtless the major cause for the colourful inexperienced waters pictured right here. (Sediments may be contributing to the vibrant inexperienced areas.)
The second mass of seawater is named “Alaskan Coastal Water,” which is hotter, much less salty, and nutrient-poor. Diatom progress is often decrease in these waters, however coccolithophores can do effectively right here. Some areas pictured right here may include this sort of plankton, recognized to impart a milky turquoise hue to the water with their plates of calcium carbonate armor.
Whereas specialists anticipate blooms to persistently present up in these waters from yr to yr, the dimension is much less constant, and the cause will not be clear.
Picture Credit score: NASA/U. S. Geological Survey/Norman Kuring/Kathryn Hansen