GEOGRAPHY IGCSE: WEATHER AND CLIMATE. Global distribution of climates. Factors affecting climate. Case study: United Kingdom.

1. IGCSE GEOGRAPHY
16. WEATHER & CLIMATE
GLOBAL
DISTRIBUTION OF
CLIMATES. FACTORS
AFFECTING CLIMATE.
CASE STUDY: UK

2. The climate in a particular part of the world will influence
its vegetation and wildlife, so is fundamental to life on
Earth.

3. Weather describes the condition of the atmosphere.
It might be sunny, hot, windy or cloudy, raining or snowing.
Climate means the average weather conditions in a particular
location based on the average weather experienced there over
30 years or more.
Global climate zones with similar flora, fauna and climate are
called biomes.

5. The weather takes into account the temperature, precipitation,
humidity and atmospheric pressure of the part of atmosphere
(air) closest to the surface of the earth.
The weather is constantly changing as temperature and
humidity change in the atmosphere.
Landmasses, such as the British Isles, experience constantly
changing weather conditions.

6. Climate refers to what is expected to happen in the atmosphere
rather than the actual conditions.
It is possible for the weather to be different from that
suggested by the climate.

7. Climatic conditions in an area can be affected by the landscape,
relief and activities taking place (both human and natural).
Climate can alter over time and space.
Within a climatic region, the climate may vary from place to
place - eg the top of a hill, the sunny side of a hill, the shaded
side of a hill and the bottom of a hill.
These areas with their small variations are called microclimates.

8. The science of monitoring and studying the atmosphere and
predicting its weather and climate is called meteorology.
People who study the weather and climate are known as
meteorologists.

10. Climates are influenced by many factors, such as proximity to
the equator or the poles and proximity to the sea, as well as
things like ocean currents, atmospheric pressure belts and
prevailing winds.
A place's climate influences the types of vegetation and
animals that live there.
It is possible to divide the world into a number of climatic
zones or biomes, each with their own characteristic climate,
vegetation and wildlife.

12. Temperatures drop the further an area is from the equator due
to the curvature of the earth.
In areas closer to the poles, sunlight has a larger area of
atmosphere to pass through and the sun is at a lower angle in
the sky.
As a result, more energy is lost and temperatures are cooler. In
addition, the presence of ice and snow nearer the poles causes
a higher albedo, meaning that more solar energy is reflected,
which also contributes to the cold.

14. Locations at a higher altitude have colder temperatures.
Temperature usually decreases by 1°C for every 100 metres in
altitude.

15. Oceans heat up and cool down much more slowly than land.
This means that coastal locations tend to be cooler in summer
and warmer in winter than places inland at the same latitude
and altitude.
Glasgow, for example, is at a similar latitude to Moscow, but is
much milder in winter because it is nearer to the coast than
Moscow.

16. Britain has a maritime climate.
A warm ocean current called the North Atlantic Drift keeps
Britain warmer and wetter than places in continental Europe.

18. The prevailing wind is the most frequent wind direction a
location experiences.
In Britain the prevailing wind is from the South West, which
brings warm, moist air from the Atlantic Ocean.
This contributes to the frequent rainfall.
When prevailing winds blow over land areas it can contribute
to creating desert climates.

20. The British Isles have variable weather that changes from day
to day between different regions and within different regions.
Consequently it is very difficult to predict or forecast the
weather.
Britain has four distinct seasons of fairly equal length - spring,
summer, autumn and winter.
In winter it is colder and wetter and the days are shorter than in
summer.

22. Different parts of the UK experience slightly different regional
climates. These can be summarised as:
North West - Cool summers, mild winters, heavy rain all year
North East - Cool summers, cold winters, steady rain all year
South East - Warm summers, mild winters, light rain all year,
especially summer
South West - Warm summers, mild winters, heavy rain all year,
especially winter
The variability of weather and climate in different regions of
the British Isles is due to the different air masses that meet
over the Isles. Each air mass brings with them different
characteristics.

24. Sunshine hours are greatest along the south coast of England
(average of 1,750 hours of sunshine per year) and are least in
mountainous areas (average less then 1,000 hours).

25. Scotland has shorter winter days and longer summer days than
the rest of the UK, because it is further north.
In north Scotland there are four more hours of daylight in
midsummer than in London.

26. On average it rains one in three days in the UK.
However, rainfall varies greatly from region to region.
It is generally wetter in the West than the East and wetter in the
highlands than the lowlands.
The wettest place is Snowdonia in Wales (average annual totals
exceeding 3,000 mm of rain a year), followed by the Scottish
Highlands, the Lake District, the Pennines and the moors of
south-west England.

27. Parts of the East, such as East Anglia, receive less than 700 mm
a year.
In most places in the UK it will rain twice as much in winter
months as in summer months.
Although in central and south-east England, and parts of south-
east Scotland, July and August are often the wettest months of
the year.
In London and Birmingham it will thunder on average 15 days a
year, compared to less than 10 elsewhere in the UK.

28. Average temperatures in UK are warmer at lower latitudes and
colder at higher latitudes.
They are also warmer at lower altitudes and colder at higher
altitudes. Average yearly temperatures at low altitude vary
from 7°C in Shetland, in northern Scotland, to 11°C on the
south-west coast of England. The coldest (and highest) place is
Ben Nevis - altitude 1,344m - where the average temperature is
less than 0°C.
The coldest months are January and February and the warmest
are July and August. In summer Scotland will be about 3°C
cooler than England. The average daily maximum temperature
in Glasgow in July is 19°C compared with 22°C in London.

29. Scotland tends to be worse affected by severe weather than the
rest of the UK. Snow is more common in highland regions than
in lowland areas, so while snow might fall on south-west
England less than 10 days a year, it will fall on the peaks of the
Cairngorm Mountains over 100 days a year.
Gale-force winds (winds of more than 34 knots or 17.2 m per
second) are most commonly caused by depressions travelling
across the Atlantic Ocean.
These depressions may pass close to or over Scotland, with
Orkney and Shetland experiencing the strongest winds.
Occasionally they can reach hurricane force, eg the storm in
October 1987.