The information given in this book is illustrated with colour photographs. You can look through the pictures until you find something similar to what you have seen. Even if it is not precisely the same, the details and page numbers given there will help to guide you to the correct description. If you know the name of the type of cloud or other phenomenon that interests you, it is easiest to use the index to find what you want. If you come across any words you do not understand, try the glossary. Space consideration prevents a full description of every photograph, but these have been very carefully chosen to show some of the vast range of different forms that may be obvserved. They are positioned to illustrate the conditions described in the text on the same or facing page.
Identifying clouds
It is a good idea to start by learning to recognise the basic cloud types. Once you are familiar with these, you can begin to identify some of the many variations that occur. Optical phenomena, together with cloud and sky colours, are described in a later section.
How the weather works
It helps to have an idea of why clouds develop in the way they do and how certain other processes affect the weather. Cloud formation is illustrated on pp.94-101, and similar sections cover water in all its forms, wind and more general descriptions of the worldâs weather patterns and climate.
Recording the weather
Satellites play an important part in modern weather forecasting, so satellite images and related weather charts are shown. The final section provides some information about how to observe the weather and photograph the sky, together with details of how actual observations are made, with information on weather forecasting, extreme weather and weather records.
Defining terms
A glossary explains some specialised terms, most of which are also covered in the text.
Note:
For reasons that are explained on p.162, winds curve in different directions in the northern and southern hemispheres. Where this difference applies, the main description is for the northern hemisphere, but southern-hemisphere directions are always indicated in square brackets: e.g. ânortherly [S] windâ.
The weather is always with us and, even in this modern age, affects nearly everything that we do. Yet we can all too easily feel that it is too complex to understand. This book aims to provide a simple introduction to the weather and to provide a guide to what is happening in the sky. The ever-changing clouds and sunshine, wind and rain, are then seen as part of even larger patterns that affect large areas of the world. The very diversity of the weather becomes a source of never-ending fascination for anyone who watches the sky.
All the photographs have been carefully selected, mostly to show âtypicalâ clouds and phenomena, rather than extreme, or rare, types that readers are unlikely to encounter. The exceptions, such as the photographs of tornadoes and hurricanes, help to illustrate the range of weather events and explain some of the processes that occur in the atmosphere.
Similarly, photographs have been chosen that show natural colours, approximately as they appeared to the eye at the time. Some phenomena, such as the purple light, present a challenge to any photographer, because of the limitations of photographic films. In these, and a few other cases, the colours observed were actually more vibrant or subtle than they appear here.
Familiarity with the different types of clouds and other phenomena, together with an idea of how and why they occur, adds considerable meaning to the official weather forecasts, and also helps you to begin to make your own predictions of changes to come. The high, fast-moving streaks of jet-stream cirrus (above) for example, may be an indication of a coming deterioration in the weather, with the approach of a depression. A different type of forthcoming weather is indicated (opposite) where the current conditions are relatively quiet, but where the more distant clouds show some signs of possible showery activity later.
Learning to interpret the sky in this way is not particularly difficult and obviously has great practical value. But even the most hardened meteorologist finds that the sky always remains a source of great beauty.
Weather forecasting is now a complex science, relying on vast amounts of data from around the world and extremely powerful supercomputers. However, once you have some idea of what is happening inside the clouds, and in the various weather systems and situations, it will become much easier to interpret forecasts, and decide for yourself what the weather is likely to do.