The UK lies in the 'battleground' between warm tropical air to the south and cold polar air to the north. As two distinctly different types of air battle for control over the mid-latitudes, the UK experiences contrasting and changeable weather.
The warm North Atlantic Drift significantly impacts the UK's climate. It carries warm water from the South Atlantic to the western shores of the UK. The prevailing south-westerly winds then spread these warmer conditions, giving the western parts of the country mild winters.
The origin and journey of the air mass can affect the climate of the UK. For example, the Polar Maritime Air Mass originates in the Poles and travels over the Arctic Sea, therefore it brings cold and wet weather. The Tropical Continental air mass originates in the tropics and travels over land, bringing hot and dry weather to the UK.
The main upland areas of the British Isles are in the west. When warm moist air is driven onto land by prevailing south-westerly winds, it is forced to rise over the mountains, where it cools, condenses and brings about precipitation. This is called relief rainfall. As a result, there is more rainfall over western upland regions than in lower areas in the east.
Our climate is continually changing. There is evidence, for example from fossils, which tell us that at certain times the world has been much warmer than it is now, and there was little ice on the North Pole. There is also evidence to suggest that at other times the ice cover was much greater than it is today. Since the 1950s, there has been evidence of a steep climb in global temperature compared to the past. This trend is linked to climate change.