Case Study: Shetland Isles –  ‘one named climate type' - Maritime Climate’

The British Isles are affected by maritime (sea) influences.  This accounts for the fact that we are far warmer than other countries of similar latitudes.  We are warmed by the sea in winter and cooled by it in summer. So we have an equable climate without extremes.

We are also warmed by the North Atlantic Drift ocean current which keeps us ice free in winter and prevents icebergs here.

The map shows the location of the Shetland Isles - the most northerly part of Britain off fthe north coast of Scotland. If anywhere in Britain should be wet and windy it is there.

The Shetland Isles shows a good example of how people live in this climate:

What is the climate like?

The climate is very unsettled to the fact that this is generally an area of low pressure, the islands are in the path of depressions.  There are at least five different masses of air affecting this area.  The most common air mass (the prevailing wind) is from the SW bringing warm wet (tropical maritime air) to the islands. 

In autumn these south-westerly winds are often in the form of hurricanes.  The winters though are wet and mild (snow is rare) due to the warming effect of the sea.  This is due to the North Atlantic Drift (or Gulf Stream) and the thermal qualities of the sea.

The temperature rarely falls below 0^oC but the wind chill makes it seem a lot colder.   The days are short due to the high latitude and so there are less hours of sunlight.  The summer it is cool and wet.  The sea now decreases the air temperature around the islands, as it is now relatively cooler than the land.

Sometimes mild air (south westerly air) blows off the sea over colder land. (see photo) This causes condensation from cooling. This is called an advection fog. The fogs are just another hazard for shipping and aircraft. In addition to gales and heavy rain.

How does this affect people and their activities?

Settlements are built in the shelter of valleys and adding extra joists to both their internal structures and their roofs strengthens houses.  Houses are therefore more costly to build.  Gardens are possible but only if they are given shelter from the wind.  Even trees are only found in the valleys due to the restriction of the windy climate.  The climate means that they need to keep a constant track of the weather as they depend on the supplies that are flown/brought in by boat.  This is also a drop off point for oilrig workers so peoples’ lives depend on accurate weather forecasting. Photo of Shetland airport.

Agriculture is limited as they only have a 3-month growing season.  They have to grow fast growing crops such as barley and potatoes.  Sheep are also kept as the wind swept, wet landscape is appropriate for grazing.

Indoor activities is another issue as there are many long evenings and poor weather days, children have activity centres to prevent them from being stuck in at home. Opposite - a photo of a leisure centre on Shetland.