Ever-changing landscape: Adventure photographer Ben Adkison tells CNN about his work on sea ice safety and logistics at US Antarctic research center McMurdo Station: Cracks in the sea ice can form and change throughout the season, sometimes creating pressure ridges where water can break through. United States Antarctic Program staffers regularly check these cracks to ensure it is safe to drive vehicles over them.
Nilas ice: Late in the fall (April and May) the sea ice begins to freeze on the surface of the water. Known as nilas ice, this glassy smooth surface initially looks black and is just a few inches thick. As the ice continues to grow, until October or November, it becomes whiter in color and can be up to eight feet thick.
Underneath the ice: The world beneath the sea ice is one of the least explored landscapes on Earth. The under-surface is covered in jagged ice crystals called platelet ice. They're formed when ice crystals floating in the water and freeze to the ice surface in the same way frost or dew forms on foggy mornings.
Icebergs: Icebergs are pieces of freshwater ice that break away from a glacier or ice shelf. While often seen by cruise ship travelers further north of McMurdo Sound, the pictured icebergs are grounded and held in by the sea ice. This one is four miles long and has been in the same spot for years.
Penguins: Emperor (pictured) and Adelie Penguins wander along the sea ice edge during the summer season. The National Science Foundation funds researchers who study how these birds are affected by climate change.
Seals: Weddell seals populate McMurdo Sound and, from a distance, can resemble large slugs. They keep holes open along sea ice cracks so that they return to the water when needed. The seals can dive to depths of up to 2,000 feet.
Logistics: United States Antarctic Program researchers and support staffers use different types of tracked vehicles to safely travel along the sea ice. A PistenBully is used to assess sea ice routes for safe travel.
Edge science: While much of the research is based on the fast ice or close to shore, certain projects require scientists to take samples at the ice edge. Specialized restraint systems are in place to keep these two scientists out of the water as they take plankton samples to study the effects of ocean acidification. Plankton is a key member of the ocean food chain so it's important to understand how climate change is affecting the population.
Melting sea ice: As temperatures rise and the sea ice weakens, the sea ice eventually breaks up into ice floes and gets carried north where it eventually melts. During January or February the ice in front of McMurdo Station can break up and disappear in less than a day.
Supplies: In late January each year, a supply ship docks at McMurdo, bringing a year's worth of food, supplies, and equipment too large to carry on cargo planes. An icebreaker breaks a channel through the sea ice to allow the ship safe passage to McMurdo. A fuel tanker will also arrive to offload millions of gallons of gas, diesel and jet fuel to support science logistics at the center.
End of season: The main research season starts in October and ends in February, taking advantage of the sunlight and warmer temperatures. The station holds up to 1,000 people each summer, but only 150 or so people stay through winter. The time is used to repair vehicles and other equipment, check and organize all the supplies from the resupply ship and ready the station for the new season. Pictured: A frozen starfish at Cape Evans on Ross Island.