The Stratosphere : Phenomena , History and Relevance

Labitzke and van Loon have been a familiar duo in the analysis and interpretation of stratospheric observations during the last three decades. Together, they have authoured dozens of papers on variations in stratospheric fields (e.g. temperature, geopotential height, zonal wind) and their possible connection to the solar cycle. Although some of their analysis has generated controversy and criticism, in part because of the lack of physical basis for the connections they propose, their work has also been an intriguing examination of the relationship between the atmosphere and solar variations. In their book, the authors stress how early observations were often initially met with scepticism and doubt when their conclusions did not agree with the already developed theory. In presenting their own research into connections between the solar cycle and stratospheric fields, the authors seem to parallel their own experiences and difficulties with those of the early observers. Regardless of whether their analysis will ever be validated by physical understanding, it is interesting to consider the connections between observational discovery and theory. In addition to the book’s historical perspective, the authors present a general overview of the stratosphere, including many of the current issues important in stratospheric research and their relationship to climate change. Although the book is not intended to be a comprehensive treatment of the stratosphere, each chapter is fairly well referenced, and should provide the interested reader with a direction to search for more detailed information. While there is considerable emphasis on the history of stratospheric observations and theory, the more descriptive sections focusing on stratospheric processes would likely be difficult to follow for the non-technical reader. For meteorologists or researchers working in the field, this book broadly describes the stratosphere using numerous figures, without the equations of more rigorous academic texts. Although on the one hand this makes for easier reading, there are those who may feel that some rigor is lacking in various descriptions of the stratosphere. Regardless, readers with an interest in the atmosphere, including its history of observations, should find this book readable and enjoyable. The book begins with a historical account of early observations of the stratosphere, and the large role the Berlin community has had on stratospheric analysis. The authors recount the early discovery of the stratosphere through some remarkable manned balloon flights, and they present some of the first daily weather maps of the stratosphere. In addition, they also discuss other early discoveries including the time varying winds in the equatorial stratosphere known as the quasi-biennial oscillation (QBO). The historical flavour of this book is refreshing and allows the reader to reflect on how far meteorology has come in the last century. Chapters 2 and 3 focus on both the general climatology of the stratosphere and the high latitude variations that occur during winter and spring. Colour plates of hemispheric temperature and geopotential height help to illustrate the seasonal variations of the stratosphere, while plots of temperature, ozone and geopotential height are used to describe the rapid changes that occur in the winter Arctic region (e.g. sudden stratospheric warming). An accurate and thorough distinction is made between the Arctic and Antarctic, and why the polar vortex in the two hemispheres is so different. These differences explain why an ozone hole forms over Antarctica and not (in general) over the Arctic. Chapter 4 is a brief description of the QBO, one of the most intriguing atmospheric variations ever discovered. The authors describe the early observations of this wind oscillation, followed by our present understanding of the processes responsible for its origin. The following chapter presents the discovery of the ozone layer and a fairly good account of the ozone depletion story. Also included is an interesting description of ozone observations over Tromsö, Norway in the 1940s. The final chapter of the book is devoted to the relationship between the stratosphere and the 11-year solar cycle. As mentioned above, this is the author’s bread and butter, and they have written extensively on this subject. In presenting their research, they are quick to point out that while physical mechanisms to explain their statistics are not yet available, the observations suggest connections that cannot be ignored. Although the descriptions of the connections between the solar cycle and the stratosphere are not always clear, and would require further reading to more adequately understand the details, they are none the less quite interesting. In the end, the authors again remind Aust. Met. Mag. 49 (2000) 159-161