Edexcel GCSE Geography – Features of Polar Regions

Edexcel GCSE Geography – Features of Polar Regions


The polar regions are the regions surrounding
the North Pole and the South Pole. The amount of heating the Earth’s surface
receives depends on a number of factors. These include solar elevation (solar angle),
cloud cover, length of day, and to a lesser extent, the length of path the Sun’s rays
must take through the atmosphere. As the rays pass through the atmosphere, some
of the radiation is absorbed, reflected or scattered. The Equator is warmer than the UK because
the angle at which the Sun’s rays strike the surface is much higher, more direct illumination
causes a more intense amount of heating. At the Poles it is colder because the angle
that the Sun’s ray strikes the Earth is much lower and the intensity of heating is less. Ice dominates the polar landscape but actually
north and south are very different because the North polar region is mostly water, the
Arctic Ocean, while the South polar region is mostly land — the continent of Antarctica. There are two main types of polar environment
— ice cap environments, where no month in the year has an average temperature above
zero degrees centigrade, and tundra environments, where at least one month has an average temperature
above zero degrees. In the polar winters , when the pole is facing
away from the sun, the sun ‘s rays don’t reach that polar region at all: it is dark for 179
days of the year at the North Pole and the South Poles themselves but at the very edge
of the polar regions it is completely dark for only about one day a year. These conditions mean considerable differences
between winter and summer in the polar regions. In the Artic polar region, summer temperatures
can be over 10 degrees centigrade but winter temperatures can be below minus 50 degrees
centigrade. This difference between seasons is called
seasonality. Because it is land rather than the sea, Antarctica
is much colder all year and summer temperatures are usually only about 2 degrees centigrade. Winters are very cold indeed. The coldest temperature ever recorded was
in an Antarctic winter: minus 89 degrees centigrade. Away from the coasts, Antarctica has and average
annual temperature of minus 57 degrees centigrade and only around 160 milimetres
of precipitation a year — it’s technically a desert. In ice cap environments no plants can grow. As well as being too cold for plants, it is
often very dry as well. 3
There are two main types of polar environment — ice cap environments, where no month in
the year has an average temperature above zero degrees centigrade, and tundra environments,
where at least one month has an average temperature above zero degrees. In the polar winters , when the pole is facing
away from the sun, the sun ‘s rays don’t reach that polar region at all: it is dark for 179
days of the year at the North Pole and the South Poles themselves but at the very edge
of the polar regions it is completely dark for only about one day a year. These conditions mean considerable differences
between winter and summer in the polar regions. In the Artic polar region, summer temperatures
can be over 10 degrees centigrade but winter temperatures can be below minus 50 degrees
centigrade. This difference between seasons is called
seasonality. Because it is land rather than the sea, Antarctica
is much colder all year and summer temperatures are usually only about 2 degrees centigrade. Winters are very cold indeed. The coldest temperature ever recorded was
in an Antarctic winter: minus 89 degrees centigrade. Away from the coasts, Antarctica has and average
annual temperature of minus 57 degrees centigrade and only around 160 milimetres
of precipitation a year — it’s technically a desert. In ice cap environments no plants can grow. As well as being too cold for plants, it is
often very dry as well. 4
Each winter the Artic Ocean freezes over but much of it melts again in the short summer. But when ice cap environments are on land,
some snow accumulates year after year and turns to ice. Eventually, enough ice accumulates for it
to start to flow down hill — a glacier. Glaciers are very powerful at eroding the
land under the ice. Some parts of the UK had ice cap environments
during Ice Ages, when the climate was colder than now. The landscapes left behind by the glaciers
are very distinctive, with deep, U-shaped valleys gouged out by the glaciers. Each winter the Artic Ocean freezes over but
much of it melts again in the short summer. But when ice cap environments are on land,
some snow accumulates year after year and turns to ice. Eventually, enough ice accumulates for it
to start to flow down hill — a glacier. Glaciers are very powerful at eroding the
land under the ice. Some parts of the UK had ice cap environments
during Ice Ages, when the climate was colder than now. The landscapes left behind by the glaciers
are very distinctive, with deep, U-shaped valleys gouged out by the glaciers. Tundra environments, where at least one month
of the year has average temperature above freezing, do have some vegetation, but it
is still too cold and dry for trees. The main things that do grow are moss and
lichen. While there may be a thin layer of soil, under
that the ground is frozen solid — called permafrost. In summer the top level of the soil unfreezes
but the permafrost doesn’t. The meltwater as nowhere to go, so the landscape
is very marshy and boggy. Animals that live in the tundra are adapted
to the very cold winters and short summers, and to the very low biodiversity. But because they are so well adapted to these
conditions, they are vulnerable to any changes. This makes the polar region a fragile environment.

Leave a Reply

Your email address will not be published. Required fields are marked *