Sympagic ecology

Solid sea ice is permeated with channels filled with salty brine.

Residents of temperate or tropical climates often assume, mistakenly, that ice and snow are devoid of life.

In fact, a number of varieties of algae such as diatoms engage in photosynthesis in arctic and alpine regions of Earth.

Additionally, the ocean has abundant plankton, and prolific algal blooms occur in the polar regions each summer as well as in high mountain lakes, bringing nutrients to those parts of the ice in contact with the water.

In the Arctic Ocean, ice algae accounts for close to half of the primary production during the summer months.

ROV image of krill grazing under the ice. In this image most krill swim in an upside down position directly under the ice. Only one animal (in the middle) is hovering in the open water.