Some icebergs appear bluish-white due to the numerous bubbles contained in the ice that scatter light. When seawater freezes it incorporates organic and inorganic components from the water. The marine-ice portion of such icebergs is clear, dark, and often green in color, because the red or yellow particles from the seawater, combine with the blue of ice and can shift the color to green. However, researchers remain curious to why?
Now, a research study led by University of Washington’s Professor Stephen Warren suspected that the reason some of the icebergs from Antarctica’s mainland are green was due to iron-oxide minerals. “Iron is a key nutrient for phytoplankton, microscopic plants that form the base of the marine food web. But iron is scarce in many areas of the ocean,” the researchers explained. “If experiments prove our theory right, it would mean green icebergs are ferrying precious iron from Antarctica’s mainland to the open sea when they break off, providing this key nutrient to the organisms that support nearly all marine life.”
Source: Sci News (Geo-physical section)