Life under the sea.

The sea ice supports a tremendous amount of life in the oceans. It provides shelter for many organisms, such as krill and crustacea pictured here, and is a rich source of oxygen as the ice and its accompanying oxygen molecules melt, and dissolved gases are in higher concentration due to the cold. The polar regions have the richest marine life in the world due to abundance of oxygen, its pristine nature, and abundance of krill and other basis of the food chain. The dwindling footprint of the sea ice threatens the health of the entire marine ecosystem, from krill to salmon to whales and everything in between. The stalactite-appearing structures in the ice are brine channels, i.e. channels formed by trapped salt water in the ice. The concentrated salt water freezes at significantly colder temperatures than the rest of the sea ice, so they are the first to thaw in the spring. In doing so, they coalesce into pockets of liquid that starts burrowing and sinking to the bottom and forms passageways out of the ice. As the super-cold concentrated salt water exits the bottom of the ice, it freezes the sea water under the ice, forming these appendages that can reach the sea floor