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CHAPTER 1

Looking at Scotland’s Landscapes

LANDSCAPES AND LANDFORMS

FIGURE 1 IS A SCOTTISH VIEW, showing landscapes that are typical of the confections of topographic shapes, sea, light, colour and atmosphere that are enjoyed by all. The object of this book is to contribute further to that enjoyment by surveying the varied landscapes of Scotland, and to help the reader to discover the stories that lie behind the rich variety.

At least two landscapes are present in this photograph: (1) in the middle distance, terraced hills in autumn gold vegetation extend down to the shores of Loch Slapin in the foreground, about 2 km in coastal length, and (2) behind this landscape rises the dark mass of the Cuillin mountains, providing one of the most famous and distinctive of Scottish landscapes, covering an area some 10 km across and giving a skyline to this photograph that is about 15 km from the photographer.

Many enthusiasts have written about the scenery of specific parts of Scotland. In this book the aim has been to cover the whole country relatively uniformly, because the variations from place to place are interesting in themselves. But this uniformity of approach has made it necessary to adopt a rather broad-brush treatment, whilst establishing the linear scale of features by the use of maps and aerial photographs in which the scale is clear in general terms. It is useful to follow earlier authors who regarded a landscape as an area of land that can be seen from one vantage point. In the case of Figure 1, the oblique aerial view covers two landscapes that are kilometres to tens of kilometres across.

Figure 1 provides a fine example of Scottish scenery that not only allows some questions of scale to be considered, but also illustrates the sorts of features that can be used to investigate the stories behind landscapes. Numerous small cliffs and bays of the coastal cliffs are visible in the foreground, where resistant bedrock provides information about the early history of events in this landscape area. The Cuillin mountains themselves are very special in the amount of bedrock that is visible in their slopes, and in the roughness that this bedrock has given to the peaks and ridges. As we shall see, the bedrock history of the Cuillin provides an explanation of the size and surface style of these remarkable hills. In the middle distance, various smaller landscape features, landforms, are visible, particularly some clearly developed terraces and cliffs. There are also smaller ridges, cross-cutting the terraces and cliffs, and often occupied by small stream valleys. These landforms directly reflect erosion of different features of the bedrock. The middle distance also illustrates the way that the gentler slopes tend to have a covering of surface blanket, often made of peat, soil or relatively weak and young sediment.

FIG 1. Aerial oblique photograph looking northwestwards towards the Cuillin mountains, Skye. (© Patricia & Angus Macdonald/Aerographica)

PEOPLE

Much has been written about landscape history, and by many people the phrase tends to have been used for the way that mankind has modified landscapes. This approach is not the main focus of this book, which deliberately concentrates on natural landscape features. However, all the landscapes described contain roads and settlements. In some cases, such as in Figure 1, these are visible but have had little impact on the landscape as a whole. In other Scottish cases, landscapes have been changed profoundly by the building works of man, and the city and town landscapes of the Midland Valley are obvious examples (Fig. 2). In other cases, subtle changes of landscape vegetation across Scotland may well be the result of man’s arrival and growing influence.

FIG 2. Satellite image covering the British Isles, showing population centres (including the Midland Valley of Scotland) picked out by man-made lighting at night. Note also the lighting on oil and gas platforms in the North Sea. (© Planetary Visions Ltd/Science Photo Library)

AREAS AND MAPS

The systematic survey of Scotland is based on a division into a grid of 19 arbitrary Areas (Fig. 3). Each Area is based loosely on the pattern of double-page areas used in the larger road atlases available, in particular the Collins Road Atlas, Britain. The object is to provide total coverage of the land areas and islands of Scotland, allowing the reader to navigate easily from place to place. At the beginning of each Area chapter, a location map explains the relationship between the Area and its neighbours. Ordnance Survey (OS) National Grid references are provided for the edges of the Area, in kilometres east and north of the arbitrary National Grid origin some 80 km west of the Isles of Scilly, southwest England.

FIG 3. Division of Scotland into 19 Areas.

The sizes and shapes of the Areas have been adjusted to fit the shape of the land areas concerned: these Areas range from 50 to 100 km wide (from west to east) and 70 to 130 km high (from south to north), covering the shape and form of the mainland and islands of Scotland. On average each Area is about 100 × 100 km. All Areas are defined by National Grid south to north and west to east lines, and except for a few oblique view maps, all our maps use the same boundary orientation so that Grid North is parallel to the up-and-down margins.

Shaded, colour-coded maps are used to convey the height and approximate shape of the land surface in each Area. These maps have been produced from data collected by the space shuttle Endeavour in February 2000 as part of NASA’s Shuttle Radar Topographic Mission (SRTM). This 11-day mission used stereo pairs of radar images to build up a Digital Elevation Model (DEM) covering nearly 80 per cent of the Earth’s surface. The original dataset used in this book is publicly available via the SRTM website (www2.jpl.nasa.gov/srtm) and consists of pixels, approximately 90 × 90 m, each of which has an associated elevation value. The absolute vertical accuracy of these data is estimated to be ± 16 m, whilst the absolute horizontal accuracy is ± 20 m.

Data on roads, railways, coastlines, town boundaries, rivers etc., suitable for reproduction at a scale of 1 : 200,000, have been made available by the Collins Bartholomew mapping agency. For further detail it is recommended that the Ordnance Survey Landranger (1 : 50,000) maps are used.

We have used ESRI ARC Geographic Information System (GIS) software in the processing and manipulating of the map data. This software makes it possible to present maps with artificial hill-shading, so that topography becomes easier to visualise. Maps presenting the directions and slope angles of sloping features are also very useful in some situations.

Many of the maps make use of a standard colour scheme, ranging from greens for the lowest ground through yellows to browns and greys for the highest ground. In general, the full range of colours has been used for each map, no matter what numerical range of heights is involved. This makes it possible to convey the fine detail of slopes and other features, whether the map covers flat ground or valleys and high peaks. To make it possible to compare between maps using this colour sequence, we have quoted the maximum elevation reached in each Area.