Book excerpt: Climatology - particularly the study of difficult and demanding weather conditions - is of major importance to pilots now that aeroplanes fly over previously unavailable routes such as the North Pole and take direct routes over very large oceans. Existing books on climatology address physical, biological or cultural environments and do not supply adequate information for the pilot. Nor do the present books on aviation meteorology provide sufficient detail on subjects such as arid climates, tropical storms and upper tropospheric winds and temperatures. This new book concentrates on aspects of climatology that are important for modern aviation, including temperature, precipitation, solar radiation, winds and regional climatic environments from around the world. Although the book has been written with the airline pilot in mind, it will also be an essential reference for Air Transport Pilot Licence training staff and for ATPL students. It will also be of interest to operational route planning staff and students of climatology.