introduction to antarctica and the antarctic, why is it so cold? jean pennycook penguinscience.com

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Introduction to Antarctica and the

Antarctic,

Why is it so cold?Jean Pennycook

penguinscience.com

Antarctica or Antarctic?

Antarctica is the 5th largest

continent on earth and

larger than the US and

Mexico combined. The

word, “Antarctica”, refers

to the continent itself.

“Antarctic” refers to the

entire southern polar

region, including the ocean

that surrounds this

continent.

Most of Antarctica is covered with over 1.25 miles of snow and ice.

These large glaciers move toward the coast under their enormous

weight and the force of gravity. When a portion floats out over the

ocean these extensions are called ice shelves. The Ross Ice Shelf is

as large as Texas.

Ross Ice Shelf

This is the edge of a glacier that is floating on the water, but is connected to the remainder that is on the land. Picture courtesy of: usap.gov

The ice shelf from the ocean. What you see is only 10% of the height of this mass of ice, 90% is under the water. This is fresh water and was made from snow fall.

The amount of ice in Antarctica plays a very influential role in

the Earth’s temperature. Ice reflects most of the sunlight back

into the atmosphere without absorbing it. This helps keep the

Earth cool.

Map courtesy of Australian Antarctic Data Centre

This map shows

the continent of

Antarctica. The

glaciers are white

and the ice

shelves are in

gray. Red dots

indicate a

science research

station.

Any place whose latitude is

greater than 66.5o S. In this case

here is a map of the Antarctic,

defined by what is called the

Antarctic Circle. It would

include most of the continent of

Antarctica and be defined as all

places that receive at least one

24 hours of daylight period and

one 24 hours of darkness once a

year. This boundary would

never change as it is defined by

latitude.

Because of the angle of the sunlight at the Poles they receive less

energy and are therefore much colder than the rest of the Earth.

Are the poles equally cold?

Average Winter oF Average Summer oF

South Pole -76 -18.5

North Pole -15 35

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Antarctica- Climate

-The ‘frozen Continent’- 90 % of the world’s ice is in Antarctica-Almost all land is covered in ice sheets- Very short cold summer-Very long cold winter-Windiest place- severe winds-Driest place with less than 4cm of rainfall-Only one period of daylight that lasts for 6 months-90% of the sun’s reflection bounces off the ice- so only 5-10% is available for warming

1

The effects of Global warming on Antarctica

-Ice caps melting causingrising sea levels , floodingsome coastal cities.

-The decline of penguins who rely on ice for their nesting habitats

-Ice shelves break up

Challenges to Life at the Poles

• Plants and Animals must adapt to:– Cold– Drought– Short growing season – Long days, Long nights

• More recently, small changes in climate can mean dramatic changes for life at the poles

Tundra Plant Facts

– Grow in clumps – May bloom from buds that are one to two

years old– Seeds may germinate and grow while still

attached to parent plant

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