Why does ice form on the surface of the ocean?
In rough water, fresh sea ice is formed by the cooling of the ocean as heat is lost into the atmosphere. The uppermost layer of the ocean is supercooled to slightly below the freezing point, at which time tiny ice platelets (frazil ice) form. With time, this process leads to a mushy surface layer, known as grease ice.
How does the sea ice form?
Sea ice is formed when ocean water is cooled below its freezing temperature of approximately -2°C or 29°F. Such ice extends on a seasonal basis over great areas of the ocean.
Where does the ocean freeze?
If the temperature is cold enough, ocean water does freeze. The polar ice cap at earth’s North Pole is a giant slab of frozen ocean water. At earth’s South Pole, the land mass constituting Antarctica complicates the situation, so most of the ice there is compacted snow.
How does sea ice formation affect ocean water salinity quizlet?
Evaporation of ocean water and formation of sea ice both increase the salinity of the ocean. However these “salinity raising” factors are continually counterbalanced by processes that decrease salinity such as the continuous input of fresh water from rivers, precipitation of rain and snow, and melting of ice.
Which ocean is frozen during winter?
the Arctic Ocean
Most of the Arctic Ocean is surrounded by Eurasia and North America. The most noteworthy thing about the Arctic Ocean is that it’s partly covered with ice throughout the whole year and almost completely covered by a layer of ice in the winter.
Why does sea ice form at the freezing point?
In contrast to fresh water, the salt in ocean water causes the density of the water to increase as it nears the freezing point, and very cold ocean water tends to sink. As a result, sea ice forms slowly, compared to freshwater ice, because salt water sinks away from the cold surface before it cools enough to freeze.
How is sea ice different from snow and ice?
The most basic difference is that sea ice forms from salty ocean water, whereas icebergs, glaciers, and lake ice form from fresh water or snow. Sea ice grows, forms, and melts strictly in the ocean.
Why does ice form on the top of a lake?
As a result, close to freezing, colder water floats to the top and the warmer water sinks to the bottom. The density of water as a function of temperature can be seen in the plot on the right. Eventually, the coldest water, which has floated to the top of the lake in wintry conditions, freezes to form a layer of ice.
How are ocean currents related to sea ice?
When ocean water in these areas gets very cold, sea ice forms. The surrounding seawater gets saltier, increases in density and sinks. Winds drive ocean currents in the upper 100 meters of the ocean’s surface. However, ocean currents also flow thousands of meters below the surface.