Page 8 - The World About Us

Svalbard
1.1.1
2.1.2

What are the features of the Polar Regions?

The Polar regions are found north
o
of the Arc c Circle (66½ N) and south
o
of the Antarc c Circle (66½ S). Both
regions are defined by their very low
annual temperatures, with
excep onally cold winters. During the
winter months the Sun doesn't rise at
all or stays very low in the sky. The
summer months are typified by long
days but the s ll very low angle of the fig.12 Esperanza Base, Argentina’s research station on the Antarctic Peninsula.
sun means that incoming solar energy While both the Arc c and con nent. There is also a powerful
is very spread out and so temperatures Antarc ca share the same cold circumpolar wind which keeps warmer
remain cool.
la tudes, the land is very different. The air far away from the con nent.
The climate of the Polar Regions is Arc c is an ocean. Here the
Antarc ca is also the highest
determined by cold descending air temperature of the sea water never con nent on Earth, with average
o
which suppresses evapora on. This is falls below -2 C. While the sea surface al tudes of 2,300m. As temperatures
already low because of the icy sea freezes and sea ice spreads southwards fall by 1 C for every 100m gained in
o
temperatures. As a result, the Polar in winter, the whole region is much height, the average temperatures of
regions are mostly deserts, receiving warmer than in Antarc ca. The sea ice o o
Antarc ca are between 20 C and 30 C
less than 250mm of rainfall each year. floats not much higher than the actual
colder than the Arc c. Temperatures at
sea level and so temperatures do not the South Pole plummet to an average
suffer the addi onal cooling effects of -62 C in winter but rise to just -55 C in
o
o
al tude.
summer.
In northern Europe, sea ice is
prevented from spreading too far south fig.14 Antarctic sea ice, winter.
by the warming effects of the North
Atlan c Dri . Temperatures at the
o
North Pole can range from -46 C to
o
-25 C. Further south in the Canadian sea ice
province of Nunavut, winter
fig.13 Antarctic coastal mountains.
o
temperature may plunge to -30 C but
o
The Antarc c Peninsula stretches rise as high as +12 C in July.
1,300 km north from the body of the
con nent towards Chile, at the southern Antarc ca is much colder than the
p of South America. The peninsula is Arc c. The con nent of Antarc ca is
mountainous, with peaks reaching circled by an intensely cold ocean Ice shelf
2,800m. The rocks on the peninsula are current in the Southern Ocean. This
rich in fossils including semi-tropical prevents warm water, from further
woodland species as well as dinosaurs. north, warming the shores of the
fig.15 Antarctic sea ice, summer .
Nature’s Fireworks
fig.16 Aurora Borealis, Northern Lights.
The Aurora is a natural light
display seem most commonly in the
Polar Regions. The light is caused by
the interac on of the Earth’s
magne c field with electrons and
protons carried in the ‘Solar wind.’
The displays, called the Aurora
Borealis in the Northern Hemisphere
and the Aurora Australis in the
Southern Hemisphere, can last from
just a few minutes to several hours.

8

Ecosystems have distinct distributions and characteristics.