This second edition has been published 12 years after the first edition that was reprinted in 1996. Unlike many second editions the authors have not highlighted the changes made between the editions though this becomes apparent when they are seen side by side. The main differences appear to be a radical updating of most of the common material and a considerable amount of new material which will be noted below. To keep this book to approximately the same size (it is 20 pages longer) some material in the first edition has been excised: a section on man-made lakes, detailed explanation of global climate models, and a chapter on greenhouse theory. These are not too much of a problem as there is still a sufficient summary of them within the present edition.
The book aims to discuss 'the concepts behind deliberate human attempts to modify the weather through cloud seeding, as well as inadvertent modification of weather and climate . . . through the emission of aerosols and gases and changes in land-use'. It is divided into three parts comprising 11 chapters and an epilogue.
Part I discusses the rise of cloud seeding from Project Cirrus in the late 1940s, through the two methodologies that developed during the 1960s and 1970s for the modification of warm and cold clouds, hail suppression and finally tropical storm modification (Project Stormfury). It then documents its decline in the 1980s because of the removal of federal funding in the United States due in part to overselling, poor experimental designs, unsubstantiated claims and wasteful expenditures.
Part II considers the inadvertent human impacts on regional weather and climate. Anthropogenic emissions of aerosols and gases now include a new section on dust. The effects of urban development, landscape changes (new), irrigation, dryland agriculture (new), desertification, deforestation, regional vegetation feedbacks (new) are all described using recent research based in the USA, Africa, Australia and the Amazon. Table VI.2 regional land-use/land-cover effects on weather and climate lists 280 references on these topics, most of them published since the first edition and the majority in the 21st century. The authors conclude that whilst there is substantial evidence for inadvertent human modification of weather and regional climate there is now a need to strengthen both the