Every
day there are reports in the newspapers and on the television
of severe weather conditions around the world. These can
include droughts where there are long periods without rainfall,
or severe gales and storms.
Drought
In some areas of the world there has been
little or no rain over the past few years. This has meant
that crops have not grown and people have gone hungry.
Africa has been particularly badly hit. In these areas
people are starving and many becoming ill from the lack
of food.
Hurricanes
Hurricanes are very bad storms that are
common in tropical regions. In these areas warm seas help
to develop large swirling storms. These have clouds, very
strong winds and very heavy rainfall. These can cause a
lot of damage as they pass over land, also bringing spectacular
thunderstorms and sometimes tornadoes.
Hurricanes are also
called cyclones or typhoons in some parts of the
world.
Hurricanes often happen in the
Caribbean and over the coast of America. They can
be as wide as 1,000 kilometres. In the West Indies
the word hurricane means'‘big wind'.
Winds can reach 300 kilometres
per hour. The most costly hurricane of recent years
was hurricane Katrina in 2005, with an estimated £150
billion worth of damage |
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Fig 1: Hurricane warning |
Snow
Snow falls when the air is very cold.
Snow forms in cold clouds when ice crystals stick together.
In some parts of the world they have
several months of the year when there is snow on the ground.
In countries such as Sweden and Finland their houses are
specially designed with extra layers of glass and double
doors to keep the cold out. Temperatures can drop to well
below freezing. Occasionally there are heavy falls of snow,
even in this country, some remote villages can be cut off
and electricity supplies interrupted.
Water cycle
 |
One
of the lowest temperatures ever recorded on earth
was -89 °C at Vostok in Antarctica. A typical
average year's snowfall in the Rocky Mountain range
in North America is about 10 metres.
The deepest snow recorded in the
UK is around this figure. The Arctic and Antarctic
polar caps are snow and ice and are many thousands
of metres deep.
The last ice age ended in northern
Europe and North America around 10,000 years ago. Historically,
ice ages have occurred at regular intervals of around
40,000-100,000 years. |
| Fig 2: Snowman on holiday |
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Fog
This can be very dangerous, especially
along motorways. People often drive too fast and too close
to the car in front.
Some cities in the world suffer from
smog. This is caused by a mixture of fog, smoke, dirt and
car fumes. In 1952 over 2,500 people died in London because
of smog caused by factories and cars.
Let's find out
Find out where the hottest and coldest
parts of the world are. Why is it hotter near the Equator
and very cold in the Arctic and Antarctic?
Some parts of the world suffer from very
dry conditions which cause drought and famine. How can
we help?
Imagine that you are a newspaper reporter
and you are the first to arrive at a snowbound village
which has been cut off for a week. Describe what you find
in a newspaper article.
Hurricanes cause a lot of damage. Design
a poster telling people how they can protect themselves
and their homes from hurricanes and storms.
Things to make
Keep a 'weather news' diary. Go through
newspapers and look on the internet to find stories of
severe weather around the world, then cut or print these
out. Collect any pictures showing storms or severe weather
conditions. Draw a large map of the world and mark where
they took place.
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Fig
3: Newspaper headlines |
Amazing facts
The first recorded 'frost fair' to be
held on a frozen River Thames was held in 1607, with the
river frequently freezing up during the 17th and 18th century,
during a period known as the Little Ice Age.
There are weather records for this country
dating back to 26 August, 55BC.
Antarctic ice is over 4,200 metres
thick in some areas. |
