About one-tenth of Earth’s land surface is covered in ice. Built up over thousands of years, most ice occurs in thick ice that cap the land at the North and South Poles. Ice also tops the peaks of high mountains, and rivers of ice called glaciers gouge deep valleys in polar and mountain regions.
Iceberg
- Icebergs form, or “calve”, when huge chunks of ice from glaciers and ice caps break off and fall into the ocean.
- Seven-eighths of an iceberg’s mass is below water. The one-eighth you see is just the “tip of the iceberg”.
- Just like ice cubes in your drink, icebergs float because the density of ice is less than water.
Iceberg shapes
Top 10 coldest places in the world
- Vostok, Antarctica:
-89°C (-129°F) - Plateau, Antarctica:
-84°C (-119°F) - Oymyakon, Russia:
-71°C (-96°F) - Verkhoyank, Russia:
-68°C (-90°F) - Northice, Greenland:
-66°C (-87°F) - Eismitte, Greenland:
-65°C (-85°F) - Snag Yukon, Canada:
-63°C (-81°F) - Prospect Creek, Alaska, United States:
-62°C (-8O°F) - Fort Selkirk, Yukon, Canada:
-59°C (-74°F) - Rogers Pass, Montana, United States:
-57°C (-70°F)
Snow to ice
Snow falls to the ground and compresses into small, round ice particles called granular ice. As the ice compacts it contains less air and forms larger granules, known as “firn”. With the pressure the firn welds into of further snow, solid, glacial ice, called “blue ice”.
In numbers
30 million cubic km
(7.2 million cubic miles)
The volume of the largest piece of ice on Earth – the Antarctic ice sheet.
70%
The percentage of fresh water frozen in the Antarctic ice sheet.
4 km
(2.5 fries) The depth of the ice cap covering South Pole.
You won’t
believe it!
Sometimes when moving icebergs scrape past each other they produce a sound like barking dogs or screeching monkeys – but a lot louder! Some of these “icequakes” are as deafening as the tremors caused by a large earthquake.
Ocean hazard
In 1912, the luxury passenger liner Titanic struck an iceberg and sank.More than 1,500 people lost their lives in the disaster.
RECORD BREAKER
In 1953, the Kutiah Glacier in Pakistan set the record for the fastest glacial sumo, covering more than 12 km (7 miles) in three months, and averaging a distance of 112 m (368 ft) per day.
Five glacial features
Cave formed by melted snow or ice ice.
Screenshot: Facebook/Video
Vertical crack in the ice as a glacier moves.
Floating ice that has broken away.
Thinning of snow and ice on a glacier.
Large piece of ice that juts out from a glacier.
Glacier anatomy
- A glacier is a huge, slow-moving river of ice.
- As a glacier moves downhill it carves steep-sided, U-shaped valleys.
- There are two main types of glaciers. Valley glaciers are streams of flowing ice that are confined within steep-walled valleys. Continental glaciers resemble huge chunks of ice and can cover a large cart of a continent, like Antarctica.
Featured image credit: World Wild Life