Climate
and Weather in Great Britain

 Weather is not the same as climate. The weather at a place is the
state of the atmosphere there at a given time or over a short period. The
weather of the British Isles is greatly variable.

The climate of
a place or region, on the other hand, represents the average weather conditions
over a long period of time.

The
climate of any place results from the interaction of a number of determining
factors, of which the most important are latitude, distance from the sea,
relief and the direction of the prevailing winds.

The
geographical position of the British Isles within latitudes 50^o to 60^o N  is
a basic factor in determining the main characteristics of the climate.
Temperature, the most  important climatic element, depends not only on the
angle at which the sun’s rays strike the earth’s surface, but also on the
duration of daylight. The length of day at London ranges from 16 hours 35
minutes on June to 7 hours 50 minutes on 21 December. British latitudes form
the temperate nature of the British climate, for the sun is never directly
overhead as in the tropical areas.

Britain’s
climate is dominated by the influence of the sea. It is much milder than that
in any other country in the same latitudes. This is due partly to the presence
of the North Atlantic Drift, or the Gulf Stream, and partly to the fact that
north-west Europe lies in a predominantly westerly wind-belt. This means that
marine influences warm the land in winter and cool in summer. This moderating
effect of the sea is in fact, the cause of the relatively small seasonal
contrasts experienced in Britain.

The
moderating effect of the ocean on air temperature is also stronger in winter
than in summer. When the surface water is cooler than the air above it – as 
frequently happens during the summer months – the    air tends to lose its heat
to the water. The lowest layers of air are chilled and become denser by
contradiction, and the chilled air tends to remain at low levels. The surface
water expands because it is warmed, and remains on the surface of the ocean.
Unless the air is turbulent, little of it can be cooled, for little heat is
exchanged.

Opposite
conditions apply in winter. The air in winter is likely to be cooler than the
surface water, so that the heat passes from water to air. Air at low levels is
warmed and expands and rises, carrying oceanic heat with it, while the chilled
surface water contracts and sinks, to be replaced by unchilled water from
below. This convectional overturning both of water and of air leads to a
vigorous exchange of heat.

The
prevailing winds in the British Isles are westerlies. They are extremely moist,
as a result of their long passage over warm waters of the North Atlantic. On
their arrival to Britain, the winds are forced upwards, and as a result
large-scale condensation takes place, clouds form and precipitation follows,
especially over the mountainous areas.

North and
north-west winds often bring heavy falls of snow to north Britain during late
October and November, but they are usually short-lived. Continental winds from
the east sometimes reach the British Isles in summer as a warm, dry air-stream,
but they are more frequently experienced in winter when they cross the north
sea and bring cold, continental-type weather to eastern and inland districts of
Great Britain.

Relief is
the most important factor controlling the distribution of temperature and
precipitation within Britain. The actual temperatures experienced in the hilly
and mountainous parts are considerably lower than those in the lowlands. The
effect of relief on precipitation is even more striking. Average annual
rainfall in Britain is about 1,100 mm. But the geographical distribution of
rainfall is largely determined by topography. The mountainous areas of the west
and north have more rainfall than the lowlands of the south and east. The
western Scottish Highlands, the Lake District (the Cumbrian mountains), Welsh
uplands and parts  of Devon and Cornwall in the south-west receive more than
2,000 mm of rainfall each year.

In
contrast, the eastern lowlands, lying in a rain-shadow area, are much drier and
usually receive little precipitation. Much of eastern and south-eastern England
(including London) receive less than 700 mm each year, and snow falls on only
15 to 18 days on the average.

Rainfall
is fairly well distributed throughout the year, although March to June are the
driest months and October to January are the wettest.

Ireland
is in the rather  a different category, for here the rain-bearing winds have
not been deprived of their moisture, and much of the Irish plain receives up to
1,200 mm of rainfall per year, usually in the form of steady and prolonged
drizzle. Snow, on the other hand, is rare, owing to the warming effects of the
Gulf Stream. The combined influences of the sea and prevailing winds are
equally evident in the general pattern of rainfall over the country.

Because
of the North Atlantic Drift and predominantly maritime air masses that reach
the British Isles from the west, the range in temperature throughout the year
is never very great. The annual mean temperature in England and Wales is about
10^oC , in Scotland and Northern Ireland about 9^oC.
July and August are the warmest months of the year, and January and February
the coldest.

 The mean
winter temperature in the north is 3^OC,the
mean summer temperature 12^oC. The corresponding figures for the
south are 5^oC and 16^oC. The mean January temperature for
London is 4^oC, and the mean July temperature 17^oC.

During a
normal summer the temperature may occasionally rise above 30^oC in
the south. Minimum temperatures of –10^oC may occur on a still clear
winter’s night in inland areas.

The
distribution of sunshine shows a general decrease from south to north – the
south has much longer periods of sunshine than the north.

It is
frequently said that Great Britain does not experience climate, but only
weather. This statement suggests that there is such a day-to-day variation in
temperature, rainfall, wind direction, wind speed and sunshine that the “average
weather conditions”, there is usually no very great variation from year  to
year or between corresponding seasons of different years.

No place
in Britain is more than 120 km from the sea. But although the British are
crowded very closely in a very small country, there is one respect in which
they are very fortunate. This is their climate. Perhaps, this is a surprising
statement because almost everyone has heard how annoying the weather usually is
in England. Because of the frequent clouds and the moisture that hangs in the
air even on fairly clear days, England has less sunshine than most countries,
and the sunlight is weaker then in other places where the air is dry and clear.
What is worse, sunshine rarely lasts long enough for a person to have time to
enjoy it. The weather changes constantly. No ordinary person can guess from one
day to another which season he will find himself in when he wakes in the
morning. Moreover, a day in January may be as warm as a warm day in July and a
day in July may be as cold as the coldest in January.

But
although the English weather is more unreliable than any weather in the world,
the English climate – average  weather – is a good one. English winters are
seldom very cold and the summers are seldom hot. Men ride to work on bicycles
all through the year. Along the south coast English gardens even contain
occasional palm trees.

The most
remarkable feature of English weather, the London fog, has as exaggerated
reputation. What makes fog thick in big industrial areas is not so much the
moisture in the air  as the soot from millions of coal fires. Such smogs (smoke
+ fog) are not frequent today. Since 1965 as a result of changes in fuel usage
and the introduction of clean air legislation, they have become less severe. It
is quite  natural that in fine, still weather there is occasionally haze in
summer and mist and fog in winter.

The
amount of rainfall in Britain is exaggerated, too. Britain seems to have a
great deal of rain because there are so many showers. But usually very little
rain falls at a time. Often the rain is hardly more than floating mist in which
you can hardly get wet. Although a period of as long as three weeks without
rain is exceptional in Britain.

It is no
wonder that, living in such an unbearable climate with so many rules and with
still more exceptions, the Englishmen talk about their weather, whatever it may
be, and their climate, too.

                                 Literature

1.Baranovski L.S., Kozikis D.D..
How Do You Do, Britain? – Moscow ,1997.