Continents of the world
Land animals in the Arctic
Arctic Fox
Arctic Rabbit
Arctic Wolf
Caribou
Moose
Arctic Hare
Ermine
Polar Bear
How does a polar bear survive in the cold?
• Low surface area to volume ratio - shorter legs and a stockier build. This reduces the surface area to lose heat from.
• Small extremities to reduce heat loss - Polar bears have small ears covered in thick fur, a very short tail and a relatively short nose all of
which help to retain heat.
• Polar bears eat a very high fat diet -It enables them to eat the blubber of the seals that they catch which is the most energy rich and
abundant part of the seal.
• Thick layer of body fat / blubber (anatomical / physiological) - This can be up 10cm (4 inches) thick, it is used both for insulation and also
for food storage to help survive when food supply may be intermittent especially in the summer months when bears often go hungry for
long periods due to not being able to hunt their preferred food of seals. Up to 50% of a polar bears weight can be fat! It also helps they
to float naturally when swimming so avoiding having to use energy to keep their head out of the water.
• Processing body fat to gain metabolic water (physiological) - Polar bears store a lot of fat which they use for energy in the process
combining it with oxygen to release carbon dioxide and metabolic water. They live in a polar desert with little access to fresh water
especially in the colder months (which are in the majority) in this way they can get extra fresh water - camels do a similar thing with their
stored fat.
• Thick camouflaged fur The coat of the polar bear is especially thick. There are two kinds of hairs, short soft dense inner hairs and longer
stiffer outer guard hairs. The coat is the same colour all year round. The colour of course provides camouflage against an icy and snowy
background.
• Thick fur on the paws to insulate them from snow and ice and also provide for grip on slippery surfaces. The paws are large in size to
help spread the bears weight over ice and snow and have blubber under the pads for extra insulation.
Falling Penguin Numbers
Antarctic Fish are being sold
for hundreds of pounds in top
restaurants.
Fishing vessels are traveling
to faraway areas to fish.
Billions of people around
the world rely on fish for
their main source of food.
Fishing ships are taking
more fish than they are
allowed in Antarctica.
Krill density had dropped by as
much as 80 per cent due to the
melting of the ice shelves.
Reduced food availability leads to
higher starvation rates and lower
breeding success in Penguins.
A decrease in the fish population
will cause a slow decline in the
Penguin population.
Dr Dave co-workers are convinced
that Global warming is the reason
behind the dramatic fall in Penguin
numbers.
85 per cent of the world’s
fisheries are currently
overfished.
Tourist boat wanting to
look at the penguins, often
visit very close to the
Penguin colony.
Pollution from increasing
tourism and ships visiting the
area is damaging the once
unspoilt environment.
Global Warming
The earth is naturally warmed by rays (or radiation) from the
sun which pass through the earth's atmosphere and are
reflected back out to space again. The atmosphere's made up
of layers of gases, some of which are called 'greenhouse gases'.
They're mostly natural and make up a kind of thermal blanket
over the earth.
This lets some of the rays back out of the atmosphere, keeping
the earth at the right temperature for animals, plants and
humans to survive (60°F/16°C).
So some global warming is good. But if extra greenhouse gases
are made, the thermal blanket gets thicker and too much heat
is kept in the earth's atmosphere. That's when global
warming's bad.
Greenhouse Gases
Who causes global warming?
USA is the greatest contributor to carbon dioxide (21%).
In general the countries are either developed or newly
industrialised.
In general the larger the country the greater amount of carbon
dioxide (population).
EU, Japan and Poland do not produce any CO2 from
deforestation
Brazil is the only country to produce more CO2 from
deforestation than fuel burning (300 million tonnes)
They are all in the northern hemisphere except for Brazil.
The USA creates 7 times more carbon dioxide than India and
Poland
CIS produces nearly 50% more CO2 than the EU.
Some effects of global warming