What are the characteristics of sea ice?

What are the characteristics of sea ice?

Sea ice is not a continuous, uniformly smooth sheet of ice, but rather is a complex surface that varies dramatically across even short distances. Sea ice is usually covered with snow, which insulates the ice and delays melting in the summer.

How is a hummock formed?

Hummocks initially form by extensional faulting as a landslide begins to move. During motion, individual large blocks develop and spread, creating an initial distribution, with small hummocks at the landslide front and larger ones at the back. As the mass spreads, hummocks remain as discrete entities.

What are the different types of ice in the Arctic?

Sea Ice Glossary

• The other kind of arctic ice is pack ice.
• Ice that forms each winter and melts each summer is known as annual ice, and is usually about six feet thick.
• Mariners have adopted a number of different names for icebergs and pack ice.
• Anchor ice.
• Bergy bit.
• Blue ice.
• Brash ice.
• Bummock.

What are the three types of sea ice?

It may be subdivided into thin first-year ice – sometimes referred to as white ice -, medium first-year ice and thick first-year ice.

What is Arctic sea ice?

Sea ice is frozen seawater that floats on the ocean surface. It forms in both the Arctic and the Antarctic in each hemisphere’s winter; it retreats in the summer, but does not completely disappear. As a result, the weather over ice-covered areas tends to be colder and drier than it would be without ice.

Is the ice in the Arctic salty?

New ice is usually very salty because it contains concentrated droplets called brine that are trapped in pockets between the ice crystals, and so it would not make good drinking water. As ice ages, the brine eventually drains through the ice, and by the time it becomes multiyear ice, nearly all of the brine is gone.

What is an earth hummock?

Definition. Earth hummocks are cryogenic mounds developed on silty and clayey materials affected by cryoturbation (Tarnocai and Zoltai 1978).

What is hummock grass?

Hummock grasses, a uniquely Australian evergreen perennial growth form, grow as mounds up to 1 m tall. Also known as spinifex or porcupine grasses, they should not be confused with Spinifex spp. of coastal areas.

What is sea ice called?

As the ocean water begins to freeze, small needle-like ice crystals called frazil form. These crystals are typically 3 to 4 millimeters (0.12 to 0.16 inches) in diameter. In calm waters, frazil crystals form a smooth, thin form of ice, called grease ice for its resemblance to an oil slick.

What are the 3 types of ice in Antarctica?

Smaller than bergy bits, growlers can be dangerous as they are difficult to see and very hard.

• DRIFT ICE. Drift Ice are pieces of floating sea ice that are 20m or more across.
• BRASH ICE.
• PACK ICE.
• FAST ICE.
• FLOE.

Why do we need Arctic sea ice?

Why is Arctic sea ice important? Arctic sea ice keeps the polar regions cool and helps moderate global climate. Sea ice has a bright surface; 80 percent of the sunlight that strikes it is reflected back into space. The oceans heat up, and Arctic temperatures rise further.

Why is the Arctic sea ice melting?

Specifically, since the industrial revolution, carbon dioxide and other greenhouse gas emissions have raised temperatures, even higher in the poles, and as a result, glaciers are rapidly melting, calving off into the sea and retreating on land.