Ross Ice Shelf

Glaciers flow off the land into the sea. Their ice spreads out and floats.

That floating ice is the ice shelf.

NASA explains that ice shelves form when slow-moving glaciers on land flow into the sea. The stiff ice stretches out on the water as a thick sheet, and it grows thinner farther from shore.

Many streams of ice from the West Antarctic Ice Sheet feed into the Ross Ice Shelf, like rivers flowing into a lake.

An ice shelf begins where land ice goes afloat on the ocean, so the Ross Ice Shelf interacts with the ocean and seafloor below and the land ice behind (ROSETTA-Ice). It currently slows, or buttresses, the fast-flowing ice streams of the West Antarctic Ice Sheet, a marine-based ice sheet that would raise global sea level by 3-4 meters if it melted.

NASA notes there is evidence to suggest ice shelves act as a brake on the glaciers that pour into them. The ROSETTA-Ice summary adds that the Ross Ice Shelf disappeared during earlier interglacial periods, suggesting it may disappear again in the future.

Pieces of ice break off the front of the ice shelf.

They float away as icebergs.

Far from shore, cracks in the ice and the pull of the tides break pieces off the shelf, making icebergs. NASA says this calving is a natural process, and because the shelf already floats, it does not make the seas rise.

In March 2000, an iceberg called B-15, about the size of the US state of Connecticut, broke off the Ross Ice Shelf.

NASA describes the shelf thinning farther from shore until cracks and tidal forces break off pieces as icebergs; calving is natural and does not raise sea level because the shelf already floats. B-15, the size of Connecticut, calved in March 2000 and later split into sections.

A 2025 study in The Cryosphere estimated that the front loses on average about 20 m of ice a year, likely mostly to wave erosion and to smaller calving set off by underwater 'feet' of ice that stick out beyond the above-water ice cliff, while ice near the front moves about 1,000 m a year.

Fish live in the dark, cold water far under the ice shelf!

Scientists found them with an underwater robot camera.

In January 2015, a team funded by the US National Science Foundation drilled through nearly 740 meters of the Ross Ice Shelf. A remotely operated camera vehicle found fish and invertebrates, including many amphipods, in the dark water below.

The water there is about -2°C (28°F) and always dark. The team said it was the farthest south that fish had ever been found.

The WISSARD team bored through nearly 740 m of the Ross Ice Shelf on 8 January 2015 at the grounding zone of the Whillans Ice Stream, about 850 km from the shelf's edge. The ROV Deep SCINI explored about 400 m² of the cavity and found fish and invertebrates, including numerous amphipods, in perpetually dark water at -2°C.

Life had been found under the Ross Ice Shelf before, but this was the closest to the South Pole such marine life had been documented, and the farthest south fish had been found. The southernmost ocean water lies about 70 km farther south, under the shelf at about 85°S (University of Bristol, 2015).

It is very cold near the ice shelf. Wear warm layers and stay dry.

Wet clothes and wind make you cold faster.

The US Centers for Disease Control and Prevention (CDC) says the most important thing in cold places is to stay dry by wearing layers and quickly changing out of damp clothing.

The body loses heat fastest in water and wet clothing, then in wind. The CDC suggests a base layer that wicks moisture away from the skin, an insulating middle layer and a hooded, windproof and waterproof shell.

The CDC Yellow Book ranks the main ways the body loses heat, fastest first: conduction (water immersion, wet clothing), convection (wind) and radiation. Its key advice for cold environments is to remain dry by layering and quickly changing moist clothing.

Its sample layers are a moisture-wicking base, an insulating middle layer (fleece, down or microfiber) and a hooded, waterproof, breathable, windproof shell. Mild hypothermia begins when the body's core temperature drops to 35°C (95°F) or lower.