in the british isles - grange primary...weather in the british isles the word weather describes the...
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Weather
In the British Isles
The word weather describes the state of
the air at a particular place and time,
whether it is warm or cold, wet or dry,
and how cloudy or windy it is.
How the Sun makes our weather
The heat from the Sun warms up the layer
of air that covers our Earth. The cycle of
day and night warming and cooling moves
the air and means it can hold more or less
water droplets. This makes the wind...
Wind
The big layer of air around the Earth
is called the atmosphere. The air in
this layer moves from place to place
when it warms up or cools down. This
moving air is known as wind. Winds
move moisture and heat around the
world and also produce much of our
weather.
Ways we use the wind’s power
Damage caused by strong winds.Trees blown down in a storm.
Rain, thunder and lightning
It rains when warm moist air cools and
condensation occurs. Warm air can hold
more water than cool air, and when the
warmer air is cooled the moisture
condenses to liquid - and it rains.
Lightning is a bright flash of electricity produced by a thunderstorm. In a
thundercloud many small bits of ice (frozen raindrops) bump into each other as they move around in the air and they create an electrical charge. When a lightning bolt travels from the cloud to the ground it actually opens up a little
space in the air. Afterwards the air rushes back in and creates a sound wave that we
hear as thunder.
Storm clouds
Lightning
©Axel Rouvin
Rain falling from storm clouds
Fog and Mist
Mist and fog look like smoke,
but they are actually tiny drops of water floating in the air. They
are like clouds that have formed at ground level.
Fog
Mist
Snow and IceSnow forms when water vapour in the atmosphere freezes into ice crystals. These are six-pointed crystals that fall in clumps and sometimes you might see them on your clothes if you are out when it’s snowing.
When water gets very cold it freezes into ice. It swells up and takes up more space when it freezes so sometimes pipes burst. Birds and animals can often walk on the ice on lakes and ponds, but usually the layer of ice is too thin for us to walk on.
A snowy day in the park
Fun in the snow
Icicles on trees
Clouds and what they mean
There are a range of different types of clouds, the main three types are stratus, cumulus and cirrus.Stratus clouds are flat and unremarkable, appearing like layered sheets.Cumulus clouds are puffy, like cotton wool floating in the sky.Cirrus clouds are thin and wispy, appearing high in the sky.
A cloud is a large group of tiny water droplets that we can see in the air.
Small fluffy cumulus clouds – fine weather.
“Mare’s tails” – can mean worse weather on its way.
“Mackerel sky” – storms on the way.
Not clouds at all...
but vapour trails from airplane engines
Sunshine, SunsetsSunlight is composed of a spectrum of colours that ranges from violet and blue at one end to orange and red on the other. At sunrise or sunset, when the sun is lower in the sky, the light takes a much longer path through the atmosphere than during the middle part of the day. More violet and blue light is scattered out of the beam along the way, and so the light which reaches our eyes early or late in the day is red.
Clouds in the evening
Rainbows and Sun Dogs
Red
Orange
Yellow
Green
Blue
Indigo
Violet
These colours are always in a rainbow, Light from the sun divides up into these colours through a prism made by water droplets in clouds.
Sometimes the rainbow seems to come down to earth
A double rainbow
The colours of the top rainbow are
reversed.
Parhelia or Sundogs
Sundogs may appear as a rainbow
coloured patch of light either side of the
sun.
A very old story says that the sun was really a
God called Helios, who drove his chariot
pulled by great horses across the sky from
morning until night, and the hunting dogs that
ran alongside him made the lights we now call
Sun Dogs.
“Sun dogs”
Sometimes it’s only possible to see one of these, the other will be on the opposite side of the sun.