Shetland Guide Book
Natural Environment

The environment of Shetland is the result of its geology and climate, combined with the effects of glaciation, plants and animals, including man, over time. The “Auld Rock” as it is so affectionately known to islanders, is well named, as the underlying rocks are ancient gneisses and schists up to 3,000m year old, which are mostly overlain by newer limestones, sandstones or volcanic intrusions. The waters around Shetland are nearly 100m deep within a short distance of the coastline in most places, and the land rises steeply from the continental shelf.

Most of the land surface is, even by geological standards, very old indeed. Shetland today represents the remnants of a very old mountain range worn down to its roots, which were at one time buried deep within the Earth. Several types of landscape occur in Shetland. these include moorland and hills, which cover most of the interior, often studded with lochs, fertile agricultural land in a few places where the rocks are favourable, coastal marshes, sandy beaches and dunes, rocky coasts and often high cliffs, long voes or sea lochs, small islands and skerries and sheltered bays and harbours.

A common coastal feature is the ayre (ON Eyrr - gravel beach) which is typically a gravelly spit, often covered with sand, which joins a small island to the Mainland, or which encloses a bay. Perhaps the best known is the tombolo leading to St Ninian’s Isle but there are many others. The voes are drowned valleys which were sculpted by glaciers. Shetland had a relatively thin ice cap in the last Ice Age, and the islands were ice free before the mainland. The huge weight of ice on the adjacent Scotland and Norway caused the land to fall and the sea bed to rise, but since the ice melted, the sea bed has sunk, sea level has risen as have the larger land areas. As a result substantial areas which were above sea level 10,000 years ago are now submerged.

The relatively mild, but windy and damp oceanic climate, is controlled by the North Atlantic weather systems with their procession of depression giving wind, rain and fine weather, but when the Scandinavian high pressure extends over Shetland, fine weather may be enjoyed for weeks at a time. The temperature of the sea ranges from a minimum of about 6o in February to a maximum of about 12 degrees in August, ensuring that Summers are cool and damp, and Winters mild.

The warmest month is August (mean max 16 degrees), and the coldest February (mean min 3 degrees). The sunniest months are however May and June, while the darkest is December. The driest months are April, May and June, while the wettest tend to be October, November, December and January. Even in the depths of winter there are always fine “days atween wadders” and the variable climate also ensures an environment with ever changing light - paradise for artists and photographers!

Photography - Photo Library - Postcards - Calendars - Guide Books

Western Isles - Orkney - Shetland - Caithness